Patent Grant
10476698
Field
The present disclosure relates to network management. More specifically, the present disclosure relates to a method and system for facilitating device-level redundancy in a link aggregation group.
Related Art
The relentless growth of the Internet has brought with it an insatiable demand for bandwidth. As a result, equipment vendors race to build larger, faster, and more versatile switches to move traffic. However, the size of a switch cannot grow infinitely. It is limited by physical space, power consumption, and design complexity, to name a few factors. More importantly, because an overly large system often does not provide economy of scale due to its complexity, simply increasing the size and throughput of a switch may prove economically unviable due to the increased per-port cost.
A flexible way to improve the scalability of a switch system is to build a fabric switch. A fabric switch is a collection of individual member switches. These member switches form a single, logical switch that can have an arbitrary number of ports and an arbitrary topology. As demands grow, customers can adopt a “pay as you grow” approach to scale up the capacity of the fabric switch.
Meanwhile, layer-2 and layer-3 (e.g., Ethernet and Internet Protocol (IP), respectively) switching technologies continue to evolve. IP facilitates routing and end-to-end data transfer in wide area networks (WANs) while providing safeguards for error-free communication. On the other hand, more routing-like functionalities are migrating into layer-2. Notably, the recent development of the Transparent Interconnection of Lots of Links (TRILL) protocol allows Ethernet switches to function more like routing devices. TRILL overcomes the inherent inefficiency of the conventional spanning tree protocol, which forces layer-2 switches to be coupled in a logical spanning-tree topology to avoid looping. TRILL allows routing bridges (RBridges) to be coupled in an arbitrary topology without the risk of looping by implementing routing functions in switches and including a hop count in the TRILL header.
As more mission-critical applications are being implemented in data communication networks, high-availability operation is becoming progressively more important as a value proposition for network architects. It can be desirable to divide a conventional aggregated link (from one device to another) among multiple network devices, often belonging to different fabric switches, such that unavailability of one fabric switch would not affect the operation of the multi-homed device.
While a link aggregation brings many desirable features to a network, some issues remain unsolved in facilitating device-level redundancy in a virtual link aggregation group. Particularly, when a plurality of member switches of a fabric switch couple both active and standby end devices via a virtual link aggregation group, existing technologies do not provide a scalable and flexible solution that takes full advantage of the virtual link aggregation group.
One embodiment of the present invention provides a switch. The switch includes a link aggregation module and a link management module. The link aggregation module establishes a virtual link aggregation group comprising a plurality of links coupled to the switch and one or more other switches. The plurality of links includes a first set of links coupling a first end device and a second set of links coupling a second end device. The link management module determines a current mode, which indicates which of the sets of links is currently active, of the virtual link aggregation group. The link management module operates the first set of links as active links carrying traffic for the virtual link aggregation group and the second set of links as standby links for the first set of links based on the current mode and a port role of a port participating in the virtual link aggregation group. The port role indicates whether the port is coupled to an active link or a backup link.
In a variation on this embodiment, the link aggregation module identifies an acknowledgment of a notification message from a remote switch of the other switches. The notification message includes port information associated with a local port participating in the virtual link aggregation group. Upon receiving the acknowledgment from a respective of the other switches, the link management module selects the first or second set of links for actively carrying traffic.
In a variation on this embodiment, the link management module determines the current mode by comparing a respective number of operational links in the first and second set of links with a protection threshold value.
In a further variation, the comparison comprises determining whether the number of operational links in one of the sets of links is lower than the protection threshold value and whether the number of operational links in another of the sets of links is greater than or equal to the protection threshold value.
In a variation on this embodiment, the link aggregation module maintains a database for the virtual link aggregation group. A respective entry in the database is associated with a port participating the virtual link aggregation group and includes a port role for the port.
In a further variation, if the port role indicates that the port is coupled to an active link and the current mode indicates that the first set of links is actively carrying traffic, the link management module marks the entry as selected to carry traffic.
In a further variation, if the port role indicates that the port is coupled to an active link and the current mode indicates that the second set of links is actively carrying traffic, the link management module marks the entry as standby.
In a variation on this embodiment, the current mode indicates that the second set of links is currently active. The link management module then operates the second set of links as active links carrying traffic for the virtual link aggregation group.
In a variation on this embodiment, the virtual link aggregation group is represented as a virtual switch identifier associated with the switch and the other switches.
In a further variation, the switch also includes a forwarding module which determines whether a local port participating in the virtual link aggregation group is coupled to a link carrying traffic for the virtual link aggregation group. If the port is coupled to a link carrying traffic, the forwarding module determines the port as an egress port of a packet, which is encapsulated in a header with the virtual switch identifier as the egress switch identifier.
In a further variation, if no local port is coupled to an operational link carrying traffic for the virtual link aggregation group, the forwarding module determines an inter-switch port as an egress port for the packet. The inter-switch port is associated with one of the other switches.
In a variation on this embodiment, the switch and the other switches are member switches of an Ethernet fabric switch, wherein the Ethernet fabric switch operates as a single Ethernet switch.
In the figures, like reference numerals refer to the same figure elements.
The following description is presented to enable any person skilled in the art to make and use the invention, and is provided in the context of a particular application and its requirements. Various modifications to the disclosed embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other embodiments and applications without departing from the spirit and scope of the present invention. Thus, the present invention is not limited to the embodiments shown, but is to be accorded the widest scope consistent with the claims.
In embodiments of the present invention, the problem of facilitating device-level redundancy in a virtual link aggregation group (VLAG) is solved by dividing the links in the virtual link aggregation group into active and standby link sets for active and standby devices, respectively.
An end device (e.g., a host machine or a customer switch) can be coupled to a plurality of switches via a virtual link aggregation group. The plurality of switches participating in the virtual link aggregation group can be referred to as “participant switches” of the virtual link aggregation group. A port participating in the virtual link aggregation group can be referred to as a participant port. One or more of the participant switches can be a member switch of a fabric switch. With existing technologies, a respective participant switch operates a respective local participant port (and the link coupled to the port) as an active port for the virtual link aggregation group. This facilitates forwarding of different packets via different participant switches.
However, a user (e.g., a customer) can deploy active-standby redundancy among the end devices (e.g., customer switches) coupled via the virtual link aggregation group. As a result, the client may couple both active and standby end devices to the same virtual link aggregation group. If a link to the active end device fails, a participant switch may start forwarding data to a standby end device even when other links to the active end device remain operational. This can cause repeated network changes, which may lead to degraded performance. Furthermore, among the participant switches, one switch typically operates as the principal switch, which maintains the state of a respective participant switch and a participant port. During failover, a respective participant switch sends and receives control messages to and from this principal switch, respectively, to determine the current state of the virtual link aggregation group. Hence, this principal switch can become a single point of failure.
To solve this problem, a virtual link aggregation group includes a set of active links and a set of standby links. One set of links is allowed to carry traffic in the virtual link aggregation group at a time. The set of active links couples at least two participant switches to an active end device. Similarly, the set of standby links couples at least two participant switches to a standby end device. Such a link aggregation group can be referred to as a redundant link aggregation group (RVLAG). It should be noted that a redundant link aggregation group can couple more than one standby end devices. Under such circumstances, the set of standby links can include one or more subsets of standby links, and each subset of standby links couples a standby end device.
A respective participant switch of the redundant virtual link aggregation group maintains a data structure, which can be referred to as a redundant virtual link aggregation group database (RVLAG database). A respective entry of the database is associated with a link in the redundant virtual link aggregation group and indicates to which set the link belongs. The set of active links carries traffic for the redundant virtual link aggregation group as long as a minimum number of links in that set remain operational. During regular operation, a respective participant switch individually selects the set of active links to carry traffic (e.g., send or receive traffic) for the redundant virtual link aggregation group. If a minimum number of links in the set of active links is not operational, a respective participant switch individually makes a distributed decision to select the set (or a subset) of standby links to carry traffic based on the entries of the database. As a result, disruption to the network is reduced by providing high availability to the links of a link set, thereby reducing data loss during a failover. In this way, a redundant virtual link aggregation group provides device-level redundancy in the network.
In some embodiments, a participant switch can be in a fabric switch. A respective switch in a fabric switch can be referred to as a member switch. In a fabric switch, any number of switches coupled in an arbitrary topology may logically operate as a single switch. The fabric switch can be an Ethernet fabric switch or a virtual cluster switch (VCS), which can operate as a single Ethernet switch. Any member switch may join or leave the fabric switch in “plug-and-play” mode without any manual configuration. In some embodiments, a respective switch in the fabric switch is a Transparent Interconnection of Lots of Links (TRILL) routing bridge (RBridge). In some further embodiments, a respective switch in the fabric switch is an Internet Protocol (IP) routing-capable switch (e.g., an IP router).
In some embodiments, a respective member switch of the fabric switch can be equipped with a persistent storage framework, which stores the configuration information in a local persistent storage. Such a persistent storage can be an object relational database. The configuration information is loaded from this persistent storage to the switch (or device) modules (e.g., the application-specific integrated circuit (ASIC) chips of the switch). In some embodiments, an Object-Relational Mapping is used to store the attribute values of a switch unit in a structured way in an object relational database. When a unit becomes operational on the switch, attribute values associated with a respective class in that unit is automatically loaded from the database. Moreover, if a class changes (e.g., a new attribute or a new relationship), that change is seamlessly incorporated into the database.
It should be noted that a fabric switch is not the same as conventional switch stacking. In switch stacking, multiple switches are interconnected at a common location (often within the same rack), based on a particular topology, and manually configured in a particular way. These stacked switches typically share a common address, e.g., an IP address, so they can be addressed as a single switch externally. Furthermore, switch stacking requires a significant amount of manual configuration of the ports and inter-switch links. The need for manual configuration prohibits switch stacking from being a viable option in building a large-scale switching system. The topology restriction imposed by switch stacking also limits the number of switches that can be stacked. This is because it is very difficult, if not impossible, to design a stack topology that allows the overall switch bandwidth to scale adequately with the number of switch units.
In contrast, a fabric switch can include an arbitrary number of switches with individual addresses, can be based on an arbitrary topology, and does not require extensive manual configuration. The switches can reside in the same location, or be distributed over different locations. These features overcome the inherent limitations of switch stacking and make it possible to build a large “switch farm,” which can be treated as a single, logical switch. Due to the automatic configuration capabilities of the fabric switch, an individual physical switch can dynamically join or leave the fabric switch without disrupting services to the rest of the network.
Furthermore, the automatic and dynamic configurability of the fabric switch allows a network operator to build its switching system in a distributed and “pay-as-you-grow” fashion without sacrificing scalability. The fabric switch's ability to respond to changing network conditions makes it an ideal solution in a virtual computing environment, where network loads often change with time.
In switch stacking, multiple switches are interconnected at a common location (often within the same rack), based on a particular topology, and manually configured in a particular way. These stacked switches typically share a common address, e.g., an IP address, so they can be addressed as a single switch externally. Furthermore, switch stacking requires a significant amount of manual configuration of the ports and inter-switch links. The need for manual configuration prohibits switch stacking from being a viable option in building a large-scale switching system. The topology restriction imposed by switch stacking also limits the number of switches that can be stacked. This is because it is very difficult, if not impossible, to design a stack topology that allows the overall switch bandwidth to scale adequately with the number of switch units.
It should also be noted that a fabric switch is distinct from a virtual local area network (VLAN). A fabric switch can accommodate a plurality of VLANs. A VLAN is typically identified by a VLAN tag. In contrast, the fabric switch is identified a fabric identifier (e.g., a VCS identifier), which is assigned to the fabric switch. A respective member switch of the fabric switch is associated with the fabric identifier. Furthermore, when a member switch of a fabric switch learns a media access control (MAC) address of an end device (e.g., via layer-2 MAC address learning), the member switch generates a notification message, includes the learned MAC address in the payload of the notification message, and sends the notification message to all other member switches of the fabric switch. In this way, a learned MAC address is shared among a respective member switch of the fabric switch.
The term “fabric switch” refers to a number of interconnected physical switches which form a single, scalable switch. These physical switches are referred to as member switches of the fabric switch. In a fabric switch, any number of switches can be connected in an arbitrary topology, and the entire group of switches functions together as one single, logical switch. This feature makes it possible to use many smaller, inexpensive switches to construct a large fabric switch, which can be viewed as a single logical switch externally. Although the present disclosure is presented using examples based on a fabric switch, embodiments of the present invention are not limited to a fabric switch. Embodiments of the present invention are relevant to any computing device that includes a plurality of devices operating as a single device.
The term “end device” can refer to any device external to a fabric switch. Examples of an end device include, but are not limited to, a host machine, a conventional layer-2 switch, a layer-3 router, or any other type of network device. Additionally, an end device can be coupled to other switches or hosts further away from a layer-2 or layer-3 network. An end device can also be an aggregation point for a number of network devices to enter the fabric switch. An end device hosting one or more virtual machines can be referred to as a host machine. In this disclosure, the terms “end device” and “host machine” are used interchangeably.
The term “switch” is used in a generic sense, and it can refer to any standalone or fabric switch operating in any network layer. “Switch” should not be interpreted as limiting embodiments of the present invention to layer-2 networks. Any device that can forward traffic to an external device or another switch can be referred to as a “switch.” Any physical or virtual device (e.g., a virtual machine/switch operating on a computing device) that can forward traffic to an end device can be referred to as a “switch.” Examples of a “switch” include, but are not limited to, a layer-2 switch, a layer-3 router, a TRILL RBridge, or a fabric switch comprising a plurality of similar or heterogeneous smaller physical and/or virtual switches.
The term “edge port” refers to a port on a fabric switch which exchanges data frames with a network device outside of the fabric switch (i.e., an edge port is not used for exchanging data frames with another member switch of a fabric switch). The term “inter-switch port” refers to a port which sends/receives data frames among member switches of a fabric switch. The terms “interface” and “port” are used interchangeably.
The term “switch identifier” refers to a group of bits that can be used to identify a switch. Examples of a switch identifier include, but are not limited to, a media access control (MAC) address, an Internet Protocol (IP) address, and an RBridge identifier. Note that the TRILL standard uses “RBridge ID” (RBridge identifier) to denote a 48-bit intermediate-system-to-intermediate-system (IS-IS) System ID assigned to an RBridge, and “RBridge nickname” to denote a 16-bit value that serves as an abbreviation for the “RBridge ID.” In this disclosure, “switch identifier” is used as a generic term, is not limited to any bit format, and can refer to any format that can identify a switch. The term “RBridge identifier” is also used in a generic sense, is not limited to any bit format, and can refer to “RBridge ID,” “RBridge nickname,” or any other format that can identify an RBridge.
The term “packet” refers to a group of bits that can be transported together across a network. “Packet” should not be interpreted as limiting embodiments of the present invention to layer-3 networks. “Packet” can be replaced by other terminologies referring to a group of bits, such as “message,” “frame,” “cell,” or “datagram.”
The term “dual-homed end device” refers to an end device that has an aggregate link to two or more switches belonging to one or more fabric switches, where the aggregate link includes multiple physical links to the different switches. The aggregate link, which includes multiple physical links, functions as one logical link to the end station. Although the term “dual” is used here, the term “dual-homed end device” does not limit the number of physical switches sharing the aggregate link to two. In various embodiments, other numbers of physical switches can share the same aggregate link. Where “dual-homed end device” is used in the present disclosure, the term “multi-homed end device” can also be used.
Network Architecture
An end device coupled to fabric switch 100 can be a host machine (e.g., a server or a computing device hosting virtual machines) or a customer networking device (e.g., a layer-2 switch or a layer-3 routing device). In this example, an end device 112, which is a host machine, is coupled to switch 102. End device 112 can host one or more virtual machines. End device 112 can include a hypervisor, which runs one or more virtual machines. End device 112 can be equipped with a Network Interface Card (NIC) with one or more ports. End device 112 couples to switch 102 via the ports of the NIC. On the other hand, end devices 122 and 124, which are coupled to fabric switch 100, are customer network devices. End devices 122 and 124 can be coupled to end device 114, which can be a host machine. Since end devices 122 and 124 are customer network devices, they can forward traffic received from fabric switch 100 to end device 114. In this disclosure, the terms “end device” and “customer network device” are used interchangeably.
In some embodiments, data communication among the member switches of fabric switch 100 is based on the TRILL protocol and a respective switch of fabric switch 100, such as switch 102, is a TRILL RBridge. Upon receiving an Ethernet frame from end device 112, switch 102 encapsulates the received Ethernet frame in a TRILL header and forwards the TRILL packet. In some embodiments, data communication among the member switches of fabric switch 100 is based on IP and a respective switch of fabric switch 100, such as switch 102, is an IP-capable switch. An IP-capable switch populates and maintains a local IP routing table, such as a routing information base, or RIB, by participating in a routing algorithm, and is capable of forwarding packets based on its IP addresses. For example, upon receiving an Ethernet frame from end device 112, switch 102 encapsulates the received Ethernet frame in an IP header and forwards the IP packet.
Switches 103, 104, and 105 are configured to operate in a special “trunked” mode for dual-homed end devices 122 and 124 and form a virtual link aggregation group 130. Switches 103, 104, and 105 can be referred to as “participant switches” of virtual link aggregation group 130. Switch identifiers 151, 152, and 153 are associated with switches 103, 104, and 105, respectively. Switch identifiers 151, 152, and 153 uniquely identify switches 103, 104, and 105, respectively, in fabric switch 100. In some embodiments, the scope of switch identifiers 151, 152, and 153 is within fabric switch 100. Ports 131 and 132 of switch 103 participate in virtual link aggregation group 130 and can be referred to as participant ports. Similarly, ports 133 and 134 of switch 104 and ports 135 and 136 of switch 105 are participant ports of virtual link aggregation group 130 as well. Port identifiers 161, 162, 163, 164, 165, and 166 are associated with participant ports 131, 132, 133, 134, 135, and 136, respectively.
With existing technologies, participant switch 105 operates ports 135 and 136 as active ports for virtual link aggregation group 130. Similarly, switches 103 and 104 operate their respective local participant ports as active ports as well. This facilitates forwarding of different packets via different participant switches. However, a user (e.g., a customer) can deploy active-standby redundancy among end devices 122 and 124 coupled via virtual link aggregation group 130. Suppose that end device 122 is the active device and end device 124 is the standby device. If a link to end device 122 (e.g., the link coupled to port 135) fails, switch 105 may start forwarding data to end device 124 even when other links to end device 122 (e.g., links coupled to ports 131-133) remain operational. This can cause repeated network changes, which may lead to degraded performance.
Furthermore, among participant switches 103, 104, and 105, one switch typically operates as the principal switch and maintains the state of a respective participant switch and a respective participant port. During a failover, a respective participant switch sends and receives control messages to and from this principal switch, respectively, to determine the current state of virtual link aggregation group 130. This principal switch can become a single point of failure and create a bottleneck.
To solve this problem, virtual link aggregation group 130 includes a set 192 of active links and a set 194 of standby links. One of these sets of links is allowed to carry traffic in virtual link aggregation group 130 at a time. Set 192 couple participant switches 103, 104, and 105 to end device 122. Similarly, set 194 couple participant switches 104 and 105 to end device 124. Such a link aggregation group can be referred to as a redundant link aggregation group. It should be noted that redundant link aggregation group 130 can couple more than one standby end devices. Under such circumstances, set 194 can include one or more subsets of standby links, and each subset of standby links couple a standby end device. In some embodiments, virtual link aggregation group 130 is associated with a group identifier, which is the same in a respective participant switch. A respective participant switch identifies virtual link aggregation group 130 by that group identifier and can maintain a mapping between the local participant ports and the group identifier.
Switches 103, 104, and 105 maintain a data structure 142, 144, and 146, respectively, to store information associated with redundant virtual link aggregation group 130. This data structure can be referred to as a redundant virtual link aggregation group database (RVLAG database). For example, a respective entry of database 142 corresponds to a port coupled to a link in redundant virtual link aggregation group 130 and is represented by the port identifier of the port. The entry can also include the switch identifier of the switch which includes the port. This entry further indicates whether the link belongs to set 192 or set 194. For example, the entry for the link between switch 104 and end device 122 can include port identifier 165 and switch identifier 153, and indicates that the link belong to set 192.
During initialization, switch 103, 104, and 105 individually select set 192 to carry traffic for redundant virtual link aggregation group 130. Links in set 192 carry traffic as long as a minimum number of links in set 192 remain operational. For example, if the minimum number is two, links in set 192 carry traffic as long as at least two links in set 192 remain operational. When one of the participant switches, such as switch 105, receives a packet for end device 114, switch 105 determines that the packet should be forwarded via redundant virtual link aggregation group 130. Switch 105 forwards the packet via port 135 coupled to an active link. If the link becomes unavailable (e.g., due a failure), switch 105 does not have a local participant port coupled to an active link. Switch 105 then forwards the packet to another participant switch, such as switch 104, coupled to an operational active link. This allows switch 105 to forward the packet to end device 122 even when the link coupled to port 135 fails. As a result, disruption to the network is reduced by providing high availability to the links of set 192 (and set 194), thereby reducing data loss during a failover.
If the number of operational links in set 192 falls below two, switches 103, 104, and 105 individually select the links in set 194 to forward traffic based on the entries of in databases 142, 144, and 146, respectively. For example, switch 103 checks the entries of database 142 to determine that the number of operational links in set 192 has fallen below two and selects set 194 to forward traffic. Since the ports coupled to the links in set 194 are mapped to the same group identifier of redundant virtual link aggregation group 130, a respective participant switch can readily select the ports coupled to the links in set 194 for forwarding traffic. It should be noted that even though switch 103 can be coupled to an operational link of set 192 and not coupled to a link in set 194, switch 103 selects set 194 to forward traffic. Switches 104 and 105 individually select set 194 to forward traffic as well. In some embodiments, selection of set 194 is atomic among the participant switches of virtual link aggregation group 130. This atomic operation ensures that the operation is executed at a participant switch when all participant switches “agree” with (e.g., can also execute) the operation.
When switch 105 receives another packet which should be forwarded via redundant virtual link aggregation group 130, switch 105 forwards the packet via port 136, which is coupled to a link in set 194. When the links of set 192 recover from the failure and at least two links in set 192 become operational, switches 103, 104, and 105 can continue to use the links in set 194 to carry traffic. In this way, redundant virtual link aggregation group 130 can reduce the number of changes in the network. However, if the number of operational links in set 194 falls below two, switches 103, 104, and 105 individually select set 192 to forward traffic. In this way, redundant virtual link aggregation group 130 facilitates device-level high availability, which is switch-level high availability in this example, to end devices 122 and 124.
During operation, switch 102 learns the MAC address of end device 112 and distributes the learned MAC address in a payload of a notification message to a respective switch of fabric switch 100. Based on the notification, a respective switch of fabric switch maintains a mapping between the MAC address of end device 112 and the switch identifier of switch 102. When end device 114 sends a packet to end device 112 via active end device 122, one of the participant switches, such as switch 104, receives the packet. Switch 104 determines from its local mapping that end device 112 is reachable via switch 102. Switch 104 encapsulates the packet in a fabric encapsulation header (e.g., a TRILL or an IP header) and assigns the virtual switch identifier of virtual switch 110 as the ingress switch identifier of the encapsulation header. Switch 104 then forwards the packet to switch 102 via an inter-switch link. Upon receiving the packet, switch 102 learns that end device 114 is reachable via virtual switch 110.
Since participant switches 103, 104, and 105 function as a single virtual switch 110, the MAC address reachability learned by a participant switch is shared with the other participant switches of redundant virtual link aggregation group 130. For example, during normal operation, end device 122 may choose to send outgoing packets from end device 114 only via the links to switch 104. As a result, only switch 104 learns the MAC address of end device 114 and associates the MAC address with the virtual switch identifier of virtual switch 110. This information is then shared by switch 104 with switches 103 and 105. When end device 112 sends a packet to end device 114, switch 102 encapsulates the packet in an encapsulation header and assigns the virtual switch identifier of virtual switch 110 as the egress switch identifier of the encapsulation header.
Since virtual switch 110 is “reachable” via any of switches 103, 104, and 105, switch 102 can forward the packet to switch 103, 104, or 105. If switch 103 receives the packet, switch 103 determines that the egress switch identifier of the encapsulation header is associated with the local switch and decapsulates the fabric encapsulation header. Switch 103 extracts the inner packet, which can be an Ethernet frame with the MAC address of end device 114 as the destination MAC address. Switch 103 determines that the MAC address of end device 114 is associated with the virtual switch identifier of virtual switch 110, which is associated with redundant virtual link aggregation group 130. Switch 103 then forwards the packet via one of its participant ports 131 and 132. In some embodiments, switch 103 deploys a selection technique (e.g., round robin or weighted selection) to select one of the participant ports 131 and 132 for forwarding the packet.
Database and State Machine
In the example in
A respective entry of database 142 corresponds to a link in redundant virtual link aggregation group 130. The entry can include one or more fields, such as a port identifier 201, a switch identifier 202, a port role 203, a port flag 204, and a port status 205. A respective field can be represented as a column of database 142. Port identifier 201 identifies a port which couples the link and can be used as the index for database 142. Switch identifier 202 identifies the switch in which the port resides. Port role 203 indicates whether a port belongs to set 192 or set 194 (e.g., active or backup) and can be preconfigured. Port flag 204 indicates whether information associated with a local participant port has been updated at other participant switches. Port status 205 indicates which set is currently selected to carry traffic for redundant virtual link aggregation group 130.
During operation, switch 103, which has switch identifier 151, discovers that its local port 131, which has port identifier 161, is a participant port of redundant virtual link aggregation group 130. Switch 103 adds the information in an entry comprising port identifier 161 in database 142. Switch 103 then sends a notification message comprising the port information to switches 104 and 105. Similarly, upon discovering that port 132, which has port identifier 162, is a participant port of redundant virtual link aggregation group 130, switch 103 adds the information in an entry comprising port identifier 162 in database 142. Switch 103 sends another notification message comprising the port information to switches 104 and 105. While waiting for an acknowledgement from switches 104 and 105, switch 103 sets the corresponding port flag to WAIT_ACK, which indicates that a notification for that port has been sent but an acknowledgement from a respective other participant switch has not been received yet.
In this example, upon receiving a respective acknowledgement for the notification for port identifier 161, switch 103 sets the corresponding port flag to ALL_ACK, which indicates that an acknowledgement from a respective other participant switch has been received. Upon setting the port flag, switch 103 determines the port status for port identifier 161 (i.e., port 131) based on its port role. Since port role associated with port identifier 161 is “active,” switch 103 sets the port status to be “selected,” which indicates that the port should carry traffic for redundant virtual link aggregation group 130. On the other hand, if the port flag remains in WAIT_ACK, switch 103 does not set a port status for port identifier 162 (i.e., for port 132). If switch 103 receives a respective acknowledgement for the notification for port identifier 162, switch 103 sets the corresponding port flag to ALL_ACK.
When switch 103 receives a notification message from switch 104, which has switch identifier 152, switch 103 discovers that port 133, which has port identifier 163, is a participant port of redundant virtual link aggregation group 130. Switch 103 adds the information in an entry comprising port identifier 161 in database 142. Since port 133 is in a remote participant switch 104, port 133 is a remote participant port for switch 103. Switch 103 sets the port flag to X, which indicates that a value of the port flag is not relevant to an entry for a remote participant port. Switch 103 then sends an acknowledgement message in response to the notification message to switch 104. Switch 103 then determines the port status for port identifier 163 (i.e., port 133) based on its port role. Since port role associated with port identifier 163 is “active,” switch 103 sets the port status to be “selected.”
Similarly, upon receiving a notification from switch 104, switch 103 adds the information associated with port 134, which has port identifier 164, in an entry comprising port identifier 164 in database 142. Switch 103 sets the port flag to X, sends an acknowledgement message to switch 104, and determines the port status for port identifier 164 (i.e., port 134). Since port role associated with port identifier 164 is “backup,” switch 103 sets the port status to be “standby.” In the same way, upon receiving respective notifications from switch 105, switch 103 adds the information associated with ports 135 and 136, which have port identifiers 165 and 166, respectively, in corresponding entries in database 142. Switch 103 sets the corresponding port flags to X, sends acknowledgement messages to switch 105 for respective notification messages, and determines the port status for port identifiers 165 and 166 (i.e., ports 135 and 136, respectively). Since port role associated with port identifiers 165 and 166 are “active” and “backup,” respectively, switch 103 sets the port status to be “selected” and “standby,” respectively.
In the example in
When switch 103 selects a minimum number of active links (i.e., marks a minimum number of entries as “selected” in database 142), switch 103 transitions from init mode 260 to an active mode 270. The minimum number of active links needed to transition from init mode 260 to active mode 270 is referred to as an initialization threshold. In some embodiments, the initialization threshold is one. In the same way, when switches 104 and 105 select a minimum number of active links from databases 144 and 146, respectively, switches 104 and 105 individually transition from init mode 260 to active mode 270. When a participant switch is in active mode 270, the active links (i.e., the links coupled to ports with an “active” port role in database 142) are selected to operate and carry traffic for redundant virtual link aggregation group 130. In the example in
If a link becomes unavailable (e.g., due to a failure), a “link down” link state change event occurs for that link. On the other hand, if an unavailable link becomes available (e.g., due to a failure recovery), a “link up” link state change event occurs for that link. A link state change event can be detected locally or received from a remote participant switch. When a participant switch, such as switch 103, detects a link state change event, switch 103 checks the number of active links and backup links (i.e., the number of links coupled to ports with a “backup” port role in database 142). If the number of active links falls below the protection threshold (e.g., due to a link down event) and the number of backup links is greater than or equal to the protection threshold, switch 103 transitions from active mode 270 to a protection mode 280. In the same way, switches 104 and 105 individually detect a link state change event, make the determinations, and transition from active mode 270 to protection mode 280.
In some embodiments, transitioning from active mode 270 to the protection mode 280 in a respective participant switch is atomic among the participant switches of redundant virtual link aggregation group 130. This atomic operation ensures that the operation is only executed at a participant switch when all participant switches “agree” with (e.g., can also execute) the operation. For example, when switch 103 determines to transition from active mode 270 to protection mode 280, switch 103 obtains a lock (e.g., a fabric-wide lock in fabric switch 100) for state machine 250. As a result, switches 104 and 105 do not transition between modes in state machine 250 as long as the lock is active. Switch 103 sends a control message to switches 104 and 105 indicating that switch 103 is ready for the transition.
Upon receiving the control message, switch 104 and 105 check whether this transition operation is allowed based on databases 144 and 146, respectively. If allowed, switches 104 and 105 send respective agreement messages back to switch 103. Upon receiving the agreement messages, switch 103 transitions from active mode 270 to protection mode 280 and releases the lock. If either switch 104 and 105 determines that the transition operation is not allowed, that switch sends a disagreement message to switch 103. If switch 103 receives a disagreement message, switch 103 cancels the transition operation and releases the lock. In this way, participant switches avoid a race condition during a transition in state machine 250.
When a participant switch, such as switch 103, is in the protection mode 280, the backup links are selected to operate and carry traffic for redundant virtual link aggregation group 130. In database 142, switch 103 sets the port status as “selected” to the entries with a “backup” port role. In the example in
Initialization
Remote participant switches individually send their respective port information associated their local ports in redundant virtual link aggregation group 130 to the local participant switch as well. From the local switch's perspective, these ports are remote participant ports and their associated port information is remote participant port information. In the example in
The switch receives respective acknowledgements from other participant switches for its local port information and adds the local port information to its local database (operation 312). The switch then determines the mode for the redundant virtual link aggregation group based on the local database (operation 314). For example, the switch can determine the mode to be active based on whether the number of ports with an “active” port role is greater than or equal to an initialization threshold. Based on the determined mode, the switch marks the port status of a respective entry in the local database (operation 316). For example, if the mode is active, the switch marks the entries with an “active” port role as “selected” and with a “backup” port role as “standby.”
If the link is not ready, the switch waits for the link to be ready (e.g., wait for partner port information) (operation 406) and continues to check whether the link is ready (operation 404). If the link is ready, the switch determines the port role of the identified port (operation 408). In some embodiments, a port role is predetermined. The port role can be predetermined based on a pre-configuration from a user. The port role can be also be determined based on a policy-based pre-computation, such as a predetermined number of ports with a superior (i.e., the highest or lowest) port identifier values are assigned one port role (e.g., “active”) and the rest of the ports are assigned another port role (e.g., “backup.”) The switch then adds the port information of the identified local port to the local redundant virtual link aggregation group database (operation 410). Adding port information to the local database includes creating an entry in the database and inserting values associated with different fields of the entry, as described in conjunction with
The switch constructs a notification message comprising the port information in its payload (operation 412). This notification message can be a fabric control message of a fabric switch. This fabric control message can be a reliable message with ensured delivery (e.g., retransmitted if the message is lost). The switch then sends the notification message to a respective other participant switch and sets a port flag of the local port to WAIT_ACK (operation 414). In some embodiments, sending a message includes identifying one or more local egress ports corresponding to the egress switch identifier of the message and transmitting the message via the identified port(s). The switch then receives an acknowledgement (e.g., an acknowledgement message) from a remote participant switch (operation 416). The switch checks whether an acknowledgement from a respective remote participant switch has been received (operation 418). If not, the switch continues to receive an acknowledgement from a remote participant switch (operation 416).
If the switch has received an acknowledgement from a respective remote participant switch, the switch sets the port flag to ALL_ACK (operation 420). The switch then runs the state machine for the redundant virtual link aggregation group based on the database, as described in conjunction with
The switch identifies port status of a respective entry in the database based on the determined mode of the redundant virtual link aggregation group (operation 460). In some embodiments, the switch receives a confirmation message from the remote participant switch indicating that the remote port is operational (operation 462). Upon receiving the confirmation message, the switch can mark this remote port to be ready to carry traffic for the redundant virtual link aggregation group (operation 464). This confirmation message can be a fabric control message and can be sent for any link aggregation in a fabric switch.
High Availability
In the example in
Upon detecting a local failure or being notified regarding a remote failure, switches 103, 104, and 105 individually updates their respective redundant virtual link aggregation group database. At this point, the links coupled to ports 131 and 135 remain operational. As a result, the number of operational links in set 192 does not fall below the protection threshold and the participant switches continue to forward traffic via the operational links in set 192. Under such circumstances, if end device 112 sends a packet to end device 114, switch 102 receives the packet. Switch 102 encapsulates the packet in a fabric encapsulation header (e.g., a TRILL or an IP header) and assigns the virtual switch identifier of virtual switch 110 as the egress switch identifier of the encapsulation header and forwards it to virtual switch 110.
If switch 104 receives the packet, switch 104 determines that traffic is currently being carried by the operational links in set 192 and the local switch does not have an operational link in set 192. As a result, even though switch 104 is associated with virtual switch 110 (i.e., the virtual switch identifier of switch 110 is also associated with switch 104), switch 104 does not decapsulates the encapsulation header. Instead, switch 104 identifies that both switches 103 and 105 have local ports coupled to an operational link in set 192. Switch 104 then forwards the packet to either switch 103 or 105. Suppose that switch 103 receives the packet and determines that the local switch has port 131 coupled to an operational link in set 192. Hence, switch 103 decapsulates the encapsulation header and forwards the inner packet via port 131.
Suppose that another failure 504 makes the link coupled to port 135 unavailable. At that point, only the link coupled to port 131 remains operational in set 192. As a result, the number of operational links in set 192 has fallen below the protection threshold and set 192 does not have enough links to carry traffic to end device 122. Since the standby links (i.e., the links in set 194) are not affected by failures 502 and 504, the number of operational links in set 194 is greater than or equal to the protection threshold. Hence, the participant switches individually transition to the protection mode, as described in conjunction with
At this point, since standby end device 124 has started receiving traffic, end device 124 can start operating as the active customer network device. End device 124 forwards this packet to end device 114. Upon receiving the packet, end device 114 relearns the MAC address of end device 112 via the port which couples end device 124. On the other hand, if end device 124 is associated with a virtual customer network device (e.g., based on a protection protocol, such as Virtual Router Redundancy Protocol (VRRP) or Virtual Switch Redundancy Protocol (VSRP)), upon becoming active, end device 114 relearns the MAC address of that virtual customer network device via the port which couples end device 124. In this way, when end device 114 forwards a packet to end device 112, end device 114 forwards the packet via the port which couples end device 124.
Suppose that a recovery from failure 502 makes the links coupled to ports 132 and 133 available. As a result, the number of operational links in set 192 becomes greater than or equal to the protection threshold. However, since the standby links of set 194 are currently selected and the number of operational links in set 194 is also greater than or equal to the protection threshold, the participant switches continue to forwarding traffic via the links in set 194. On the other hand, suppose that another failure 506 makes the link coupled to port 135 unavailable. At that point, the number of operational links in set 192 is greater than or equal to the protection threshold, but the number of operational links in set 194 has fallen below the protection threshold. As a result, the participant switches individually transition back to the active mode and start forwarding traffic via the operational links in set 192. These links are coupled to ports 131, 132, and 133.
On the other hand, when switch 103 receives a notification from switch 104 regarding unavailability of port 133, switch 103 sends back an acknowledgement and removes the entry comprising port identifier 163 of port 133 from database 142. Switch 103 again runs state machine 250 based on database 142 and determines that redundant virtual link aggregation group 130 remains in active mode 270, as described in conjunction with
On the other hand, when switch 103 receives a notification from switch 104 regarding availability of port 133, switch 103 sends back an acknowledgement and adds an entry comprising port identifier 163 of port 133 to database 142. Switch 103 again runs state machine 250 based on database 142 and determines that redundant virtual link aggregation group 130 remains in protection mode 280, as described in conjunction with
Recovery Operations
The switch then receives an acknowledgement (e.g., an acknowledgement message) from a remote participant switch (operation 608). The switch checks whether an acknowledgement from a respective remote participant switch has been received (operation 610). If not, the switch continues to receive an acknowledgement from a remote participant switch (operation 608). If the switch has received an acknowledgement from a respective remote participant switch, the switch sets the port flag to ALL_ACK (operation 612). The switch then checks the state change type (operation 614). If it is a “link down” state change (e.g., a link has become unavailable), the switch removes the entry comprising the port information of the local participant port from the local redundant virtual link aggregation group database (operation 616). If it is a “link up” state change (e.g., a link has become available), the switch adds an entry comprising the port information of the local participant port to the local database (operation 618).
Upon removing (operation 616) or adding (operation 618) the port information, the switch runs the state machine for the redundant virtual link aggregation group based on the database, as described in conjunction with
Upon removing (operation 658) or adding (operation 660) the port information, the switch runs the state machine for the redundant virtual link aggregation group based on the database, as described in conjunction with
Forwarding
If the switch is not coupled to a selected link, the switch identifies the local inter-switch port(s) associated with the virtual switch identifier based on the local forwarding table (operation 706). In some embodiments, the switch maintains a mapping between the local inter-switch ports associated with remote participant switch(es) and the virtual switch identifier in the local forwarding table. If the switch has a plurality of remote participant switches with a “selected” port status (e.g., switch 103 in protection mode 280), the switch selects one of the identified local ports as the egress port for the fabric-encapsulated packet based on a switch selection policy (e.g., round robin, shortest distance, bandwidth, latency, hashing, etc.) (operation 708). The switch then transmits the fabric-encapsulated packet via the selected egress port (operation 710).
If the switch is coupled to a selected link, the switch decapsulates the fabric-encapsulation header and obtains the inner packet (e.g., an Ethernet frame) (operation 712). The switch identifies the local participant port(s) coupled to the corresponding selected link(s) based on the local forwarding table (operation 714). In some embodiments, the switch maintains a mapping between the local participant ports associated with the virtual switch identifier and the destination MAC address of the inner packet in the local forwarding table. If the switch has a plurality of such local ports (e.g., switch 103 in active mode 270), the switch selects one of the identified local ports as the egress port for the inner frame based on a port selection policy (e.g., round robin, bandwidth, hashing, etc.) (operation 716). The switch then transmits the inner packet via the selected egress port (operation 718).
Exemplary Switch
In some embodiments, switch 800 maintains a membership in a fabric switch, as described in conjunction with
Communication ports 802 can include inter-switch communication channels for communication within the fabric switch. This inter-switch communication channel can be implemented via a regular communication port and based on any open or proprietary format. Communication ports 802 can also include one or more extension communication ports for communication between neighbor fabric switches. Communication ports 802 can include one or more TRILL ports capable of receiving frames encapsulated in a TRILL header. Communication ports 802 can also include one or more IP ports capable of receiving IP packets. An IP port is capable of receiving an IP packet and can be configured with an IP address. Packet processor 810 can process TRILL-encapsulated frames and/or IP packets.
During operation, link aggregation module 830 establishes a redundant virtual link aggregation group comprising a plurality of links coupled to switch 800 and one or more other participant switches. The plurality of links includes a first set of links coupling a first customer device and a second set of links coupling a second customer device, as described in conjunction with
Link management module 832 can determine the current mode by comparing a number of operational links in the first and second sets of links with a protection threshold value. In some embodiments, link management module 832 identifies an acknowledgment of a notification message from a remote participant switch. Upon receiving the acknowledgment from a respective remote participant switch, link management module 832 determines whether the first or second set of links is actively carrying traffic
In some embodiments, link aggregation module 830 maintains a redundant virtual link aggregation group database for the virtual link aggregation group, as described in conjunction with
In some embodiments, the virtual link aggregation group is represented as a virtual switch identifier associated with switch 800 and the other participant switches, as described in conjunction with
Note that the above-mentioned modules can be implemented in hardware as well as in software. In one embodiment, these modules can be embodied in computer-executable instructions stored in a memory which is coupled to one or more processors in switch 800. When executed, these instructions cause the processor(s) to perform the aforementioned functions.
In summary, embodiments of the present invention provide a switch and a method for facilitating a redundant virtual link aggregation group. In one embodiment, the switch includes a link aggregation module and a link management module. The link aggregation module establishes a virtual link aggregation group comprising a plurality of links coupled to the switch and one or more other switches. The plurality of links includes a first set of links coupling a first end device and a second set of links coupling a second end device. The link management module determines a current mode, which indicates which of the sets of links is currently active, of the virtual link aggregation group. The link management module operates the first set of links as active links carrying traffic for the virtual link aggregation group and the second set of links as standby links for the first set of links based on the current mode and a port role of a port participating in the virtual link aggregation group. The port role indicates whether the port is coupled to an active link or a backup link.
The methods and processes described herein can be embodied as code and/or data, which can be stored in a computer-readable non-transitory storage medium. When a computer system reads and executes the code and/or data stored on the computer-readable non-transitory storage medium, the computer system performs the methods and processes embodied as data structures and code and stored within the medium.
The methods and processes described herein can be executed by and/or included in hardware modules or apparatus. These modules or apparatus may include, but are not limited to, an application-specific integrated circuit (ASIC) chip, a field-programmable gate array (FPGA), a dedicated or shared processor that executes a particular software module or a piece of code at a particular time, and/or other programmable-logic devices now known or later developed. When the hardware modules or apparatus are activated, they perform the methods and processes included within them.
The foregoing descriptions of embodiments of the present invention have been presented only for purposes of illustration and description. They are not intended to be exhaustive or to limit this disclosure. Accordingly, many modifications and variations will be apparent to practitioners skilled in the art. The scope of the present invention is defined by the appended claims.
This application claims the benefit of U.S. Provisional Application No. 61/968,141, titled “Distributed Active-Passive redundancy in vLAG,” by inventors Shivalingayya Chikkamath, Prabu Thayalan, and Mythilikanth Raman, filed 20 Mar. 2014; and U.S. Provisional Application No. 61/975,625, titled “Distributed Active-Passive redundancy in vLAG,” by inventors Shivalingayya Chikkamath, Prabu Thayalan, and Mythilikanth Raman, filed 4 Apr. 2014, the disclosures of which are incorporated by reference herein. The present disclosure is related to U.S. Pat. No. 8,867,552, Ser. No. 13/087,239, titled “Virtual Cluster Switching,” by inventors Suresh Vobbilisetty and Dilip Chatwani, issued 21 Oct. 2014; and U.S. Pat. No. 8,665,886, Ser. No. 12/725,249, titled “Redundant Host Connection in a Routed Network,” by inventors Somesh Gupta, Anoop Ghanwani, Phanidhar Koganti, and Shunjia Yu, issued 4 Mar. 2014, the disclosures of which are incorporated by reference herein.
| Number | Name | Date | Kind |
|---|---|---|---|
| 829529 | Keathley | Aug 1906 | A |
| 5390173 | Spinney | Feb 1995 | A |
| 5802278 | Isfeld | Sep 1998 | A |
| 5878232 | Marimuthu | Mar 1999 | A |
| 5879173 | Poplawski | Mar 1999 | A |
| 5959968 | Chin | Sep 1999 | A |
| 5973278 | Wehrill, III | Oct 1999 | A |
| 5983278 | Chong | Nov 1999 | A |
| 5995262 | Hirota | Nov 1999 | A |
| 6041042 | Bussiere | Mar 2000 | A |
| 6085238 | Yuasa | Jul 2000 | A |
| 6092062 | Lohman | Jul 2000 | A |
| 6104696 | Kadambi | Aug 2000 | A |
| 6122639 | Babu | Sep 2000 | A |
| 6185214 | Schwartz | Feb 2001 | B1 |
| 6185241 | Sun | Feb 2001 | B1 |
| 6295527 | McCormack | Sep 2001 | B1 |
| 6331983 | Haggerty | Dec 2001 | B1 |
| 6438106 | Pillar | Aug 2002 | B1 |
| 6498781 | Bass | Dec 2002 | B1 |
| 6542266 | Phillips | Apr 2003 | B1 |
| 6553029 | Alexander | Apr 2003 | B1 |
| 6571355 | Linnell | May 2003 | B1 |
| 6583902 | Yuen | Jun 2003 | B1 |
| 6633761 | Singhal | Oct 2003 | B1 |
| 6636963 | Stein | Oct 2003 | B1 |
| 6771610 | Seaman | Aug 2004 | B1 |
| 6816462 | Booth, III | Nov 2004 | B1 |
| 6870840 | Hill | Mar 2005 | B1 |
| 6873602 | Ambe | Mar 2005 | B1 |
| 6920503 | Nanji | Jul 2005 | B1 |
| 6937576 | DiBenedetto | Aug 2005 | B1 |
| 6956824 | Mark | Oct 2005 | B2 |
| 6957269 | Williams | Oct 2005 | B2 |
| 6975581 | Medina | Dec 2005 | B1 |
| 6975864 | Singhal | Dec 2005 | B2 |
| 7016352 | Chow | Mar 2006 | B1 |
| 7061877 | Gummalla | Jun 2006 | B1 |
| 7062177 | Grivna | Jun 2006 | B1 |
| 7097308 | Kim et al. | Aug 2006 | B2 |
| 7173934 | Lapuh | Feb 2007 | B2 |
| 7197308 | Singhal | Mar 2007 | B2 |
| 7206288 | Cometto | Apr 2007 | B2 |
| 7274694 | Cheng | Sep 2007 | B1 |
| 7310664 | Merchant | Dec 2007 | B1 |
| 7313637 | Tanaka | Dec 2007 | B2 |
| 7316031 | Griffith | Jan 2008 | B2 |
| 7330897 | Baldwin | Feb 2008 | B2 |
| 7380025 | Riggins | May 2008 | B1 |
| 7397768 | Betker | Jul 2008 | B1 |
| 7397794 | Lacroute | Jul 2008 | B1 |
| 7430164 | Bare | Sep 2008 | B2 |
| 7453888 | Zabihi | Nov 2008 | B2 |
| 7477894 | Sinha | Jan 2009 | B1 |
| 7480258 | Shuen | Jan 2009 | B1 |
| 7508757 | Ge | Mar 2009 | B2 |
| 7558195 | Kuo | Jul 2009 | B1 |
| 7558273 | Grosser | Jul 2009 | B1 |
| 7571447 | Ally | Aug 2009 | B2 |
| 7599901 | Mital | Oct 2009 | B2 |
| 7653056 | Dianes | Jan 2010 | B1 |
| 7688960 | Aubuchon | Mar 2010 | B1 |
| 7690040 | Frattura | Mar 2010 | B2 |
| 7716370 | Devarapalli | May 2010 | B1 |
| 7720076 | Dobbins | May 2010 | B2 |
| 7729296 | Choudhary | Jun 2010 | B1 |
| 7787480 | Mehta | Aug 2010 | B1 |
| 7792920 | Istvan | Sep 2010 | B2 |
| 7796593 | Ghosh | Sep 2010 | B1 |
| 7801021 | Triantafillis | Sep 2010 | B1 |
| 7808992 | Homchaudhuri | Oct 2010 | B2 |
| 7836332 | Hara | Nov 2010 | B2 |
| 7843906 | Chidambaram et al. | Nov 2010 | B1 |
| 7843907 | Abou-Emara | Nov 2010 | B1 |
| 7860097 | Lovett | Dec 2010 | B1 |
| 7898959 | Arad | Mar 2011 | B1 |
| 7912091 | Krishnan | Mar 2011 | B1 |
| 7924837 | Shabtay | Apr 2011 | B1 |
| 7937438 | Miller | May 2011 | B1 |
| 7937756 | Kay | May 2011 | B2 |
| 7945941 | Sinha | May 2011 | B2 |
| 7949638 | Goodson | May 2011 | B1 |
| 7957386 | Aggarwal | Jun 2011 | B1 |
| 8018938 | Fromm | Sep 2011 | B1 |
| 8027354 | Portolani | Sep 2011 | B1 |
| 8054832 | Shukla | Nov 2011 | B1 |
| 8068442 | Kompella | Nov 2011 | B1 |
| 8078704 | Lee | Dec 2011 | B2 |
| 8090805 | Chawla | Jan 2012 | B1 |
| 8102781 | Smith | Jan 2012 | B2 |
| 8102791 | Tang | Jan 2012 | B2 |
| 8116307 | Thesayi | Feb 2012 | B1 |
| 8125928 | Mehta | Feb 2012 | B2 |
| 8134922 | Elangovan | Mar 2012 | B2 |
| 8155150 | Chung | Apr 2012 | B1 |
| 8160063 | Maltz | Apr 2012 | B2 |
| 8160080 | Arad | Apr 2012 | B1 |
| 8170038 | Belanger | May 2012 | B2 |
| 8175107 | Yalagandula | May 2012 | B1 |
| 8095774 | Lambeth | Jun 2012 | B1 |
| 8194674 | Pagel | Jun 2012 | B1 |
| 8195774 | Lambeth | Jun 2012 | B2 |
| 8204061 | Sane | Jun 2012 | B1 |
| 8213313 | Doiron | Jul 2012 | B1 |
| 8213336 | Smith | Jul 2012 | B2 |
| 8230069 | Korupolu | Jul 2012 | B2 |
| 8239960 | Frattura | Aug 2012 | B2 |
| 8249069 | Raman | Aug 2012 | B2 |
| 8270401 | Barnes | Sep 2012 | B1 |
| 8295291 | Ramanathan | Oct 2012 | B1 |
| 8295921 | Ramanathan | Oct 2012 | B2 |
| 8301686 | Appajodu | Oct 2012 | B1 |
| 8339994 | Gnanasekaran | Dec 2012 | B2 |
| 8351352 | Eastlake | Jan 2013 | B1 |
| 8369335 | Jha | Feb 2013 | B2 |
| 8369347 | Xiong | Feb 2013 | B2 |
| 8392496 | Linden | Mar 2013 | B2 |
| 8451717 | Srikrishnan | May 2013 | B2 |
| 8462774 | Page | Jun 2013 | B2 |
| 8465774 | Page | Jun 2013 | B2 |
| 8520595 | Yadav | Aug 2013 | B2 |
| 8553710 | White | Oct 2013 | B1 |
| 8595479 | Radhakrishnan | Nov 2013 | B2 |
| 8599850 | Jha | Dec 2013 | B2 |
| 8599864 | Chung | Dec 2013 | B2 |
| 8615008 | Natarajan | Dec 2013 | B2 |
| 8619788 | Sankaran | Dec 2013 | B1 |
| 8625616 | Vobbilisetty | Jan 2014 | B2 |
| 8705526 | Hasan | Apr 2014 | B1 |
| 8706905 | McGlaughlin | Apr 2014 | B1 |
| 8717895 | Koponen | May 2014 | B2 |
| 8724456 | Hong | May 2014 | B1 |
| 8730963 | Grosser, Jr. | May 2014 | B1 |
| 8792501 | Rustagi | Jul 2014 | B1 |
| 8798045 | Aybay | Aug 2014 | B1 |
| 8798055 | An | Aug 2014 | B1 |
| 8804732 | Hepting | Aug 2014 | B1 |
| 8804736 | Drake | Aug 2014 | B1 |
| 8806031 | Kondur | Aug 2014 | B1 |
| 8826385 | Congdon | Sep 2014 | B2 |
| 8918631 | Kumar | Dec 2014 | B1 |
| 8937865 | Kumar | Jan 2015 | B1 |
| 8948181 | Kapadia | Feb 2015 | B2 |
| 8971173 | Choudhury | Mar 2015 | B1 |
| 9019976 | Gupta | Apr 2015 | B2 |
| 9178793 | Marlow | Nov 2015 | B1 |
| 9231890 | Vobbilisetty | Jan 2016 | B2 |
| 9350680 | Thayalan | May 2016 | B2 |
| 9401818 | Venkatesh | Jul 2016 | B2 |
| 9438447 | Basso | Sep 2016 | B2 |
| 9450870 | Ananthapadmanabha | Sep 2016 | B2 |
| 9524173 | Guntaka | Dec 2016 | B2 |
| 9626255 | Guntaka | Apr 2017 | B2 |
| 9628407 | Guntaka | Apr 2017 | B2 |
| 20010005527 | Vaeth | Jun 2001 | A1 |
| 20010055274 | Hegge | Dec 2001 | A1 |
| 20020021701 | Lavian | Feb 2002 | A1 |
| 20020027885 | Ben-Ami | Mar 2002 | A1 |
| 20020039350 | Wang | Apr 2002 | A1 |
| 20020054593 | Morohashi | May 2002 | A1 |
| 20020087723 | Williams | Jul 2002 | A1 |
| 20020091795 | Yip | Jul 2002 | A1 |
| 20020138628 | Tingley | Sep 2002 | A1 |
| 20020161867 | Cochran | Oct 2002 | A1 |
| 20030026290 | Umayabashi | Feb 2003 | A1 |
| 20030041085 | Sato | Feb 2003 | A1 |
| 20030093567 | Lolayekar | May 2003 | A1 |
| 20030097464 | Martinez | May 2003 | A1 |
| 20030097470 | Lapuh | May 2003 | A1 |
| 20030123393 | Feuerstraeter | Jul 2003 | A1 |
| 20030147385 | Montalvo | Aug 2003 | A1 |
| 20030152075 | Hawthorne | Aug 2003 | A1 |
| 20030174706 | Shankar | Sep 2003 | A1 |
| 20030189905 | Lee | Oct 2003 | A1 |
| 20030189930 | Terrell | Oct 2003 | A1 |
| 20030208616 | Laing | Nov 2003 | A1 |
| 20030216143 | Roese | Nov 2003 | A1 |
| 20030223428 | BlanquerGonzalez | Dec 2003 | A1 |
| 20030233534 | Bernhard | Dec 2003 | A1 |
| 20040001433 | Gram | Jan 2004 | A1 |
| 20040003094 | See | Jan 2004 | A1 |
| 20040010600 | Baldwin | Jan 2004 | A1 |
| 20040088668 | Bornowski | Jan 2004 | A1 |
| 20040037295 | Tanaka | Feb 2004 | A1 |
| 20040047349 | Fujita | Mar 2004 | A1 |
| 20040049699 | Griffith | Mar 2004 | A1 |
| 20040057430 | Paavolainen | Mar 2004 | A1 |
| 20040081171 | Finn | Apr 2004 | A1 |
| 20040088437 | Stimac | May 2004 | A1 |
| 20040095900 | Siegel | May 2004 | A1 |
| 20040117508 | Shimizu | Jun 2004 | A1 |
| 20040120326 | Yoon | Jun 2004 | A1 |
| 20040165595 | Holmgren | Aug 2004 | A1 |
| 20040165596 | Garcia | Aug 2004 | A1 |
| 20040205234 | Barrack | Oct 2004 | A1 |
| 20040213232 | Regan | Oct 2004 | A1 |
| 20040225725 | Enomoto | Nov 2004 | A1 |
| 20040243673 | Goyal | Dec 2004 | A1 |
| 20050007951 | Lapuh | Jan 2005 | A1 |
| 20050025179 | McLaggan | Feb 2005 | A1 |
| 20050036488 | Kalkunte | Feb 2005 | A1 |
| 20050044199 | Shiga | Feb 2005 | A1 |
| 20050074001 | Mattes | Apr 2005 | A1 |
| 20050094568 | Judd | May 2005 | A1 |
| 20050094630 | Valdevit | May 2005 | A1 |
| 20050108375 | Hallak-Stamler | May 2005 | A1 |
| 20050111352 | Ho | May 2005 | A1 |
| 20050122979 | Gross | Jun 2005 | A1 |
| 20050152335 | Lodha | Jul 2005 | A1 |
| 20050157751 | Rabie | Jul 2005 | A1 |
| 20050169188 | Cometto | Aug 2005 | A1 |
| 20050195813 | Ambe | Sep 2005 | A1 |
| 20050207423 | Herbst | Sep 2005 | A1 |
| 20050213561 | Yao | Sep 2005 | A1 |
| 20050220096 | Friskney | Oct 2005 | A1 |
| 20050259586 | Hafid | Nov 2005 | A1 |
| 20050265330 | Suzuki | Dec 2005 | A1 |
| 20050265356 | Kawarai | Dec 2005 | A1 |
| 20050278565 | Frattura | Dec 2005 | A1 |
| 20060007869 | Hirota | Jan 2006 | A1 |
| 20060018302 | Ivaldi | Jan 2006 | A1 |
| 20060029055 | Perera | Feb 2006 | A1 |
| 20060034292 | Wakayama | Feb 2006 | A1 |
| 20060036648 | Frey | Feb 2006 | A1 |
| 20060036765 | Weyman | Feb 2006 | A1 |
| 20060039366 | Ghosh | Feb 2006 | A1 |
| 20060059163 | Frattura | Mar 2006 | A1 |
| 20060062187 | Rune | Mar 2006 | A1 |
| 20060072550 | Davis | Apr 2006 | A1 |
| 20060083172 | Jordan | Apr 2006 | A1 |
| 20060083254 | Ge | Apr 2006 | A1 |
| 20060093254 | Ge | Apr 2006 | A1 |
| 20060092860 | Higashitaniguchi | May 2006 | A1 |
| 20060098589 | Kreeger | May 2006 | A1 |
| 20060126511 | Youn | Jun 2006 | A1 |
| 20060140130 | Kalkunte | Jun 2006 | A1 |
| 20060155828 | Ikeda | Jul 2006 | A1 |
| 20060168109 | Warmenhoven | Jul 2006 | A1 |
| 20060184937 | Abels | Aug 2006 | A1 |
| 20060206655 | Chappell | Sep 2006 | A1 |
| 20060209886 | Silberman | Sep 2006 | A1 |
| 20060221960 | Borgione | Oct 2006 | A1 |
| 20060227776 | Chandrasekaran | Oct 2006 | A1 |
| 20060235995 | Bhatia | Oct 2006 | A1 |
| 20060242311 | Mai | Oct 2006 | A1 |
| 20060242398 | Fontijn | Oct 2006 | A1 |
| 20060245439 | Sajassi | Nov 2006 | A1 |
| 20060251067 | Desanti | Nov 2006 | A1 |
| 20060256767 | Suzuki | Nov 2006 | A1 |
| 20060265515 | Shiga | Nov 2006 | A1 |
| 20060285499 | Tzeng | Dec 2006 | A1 |
| 20060291480 | Cho | Dec 2006 | A1 |
| 20060294413 | Filz | Dec 2006 | A1 |
| 20070036178 | Hares | Feb 2007 | A1 |
| 20070053294 | Ho | Mar 2007 | A1 |
| 20070061817 | Atkinson | Mar 2007 | A1 |
| 20070074052 | Hemmah | Mar 2007 | A1 |
| 20070081530 | Nomura | Apr 2007 | A1 |
| 20070083625 | Chamdani | Apr 2007 | A1 |
| 20070086362 | Kato | Apr 2007 | A1 |
| 20070094464 | Sharma | Apr 2007 | A1 |
| 20070097968 | Du | May 2007 | A1 |
| 20070098006 | Parry | May 2007 | A1 |
| 20070110068 | Sekiguchi | May 2007 | A1 |
| 20070116224 | Burke | May 2007 | A1 |
| 20070116422 | Reynolds | May 2007 | A1 |
| 20070121617 | Kanekar | May 2007 | A1 |
| 20070130295 | Rastogi | Jun 2007 | A1 |
| 20070156659 | Lim | Jul 2007 | A1 |
| 20070177525 | Wijnands | Aug 2007 | A1 |
| 20070177597 | Ju | Aug 2007 | A1 |
| 20070183313 | Narayanan | Aug 2007 | A1 |
| 20070183393 | Boyd | Aug 2007 | A1 |
| 20070206762 | Chandra | Sep 2007 | A1 |
| 20070211712 | Fitch | Sep 2007 | A1 |
| 20070220059 | Lu | Sep 2007 | A1 |
| 20070226214 | Smits | Sep 2007 | A1 |
| 20070230472 | Jesuraj | Oct 2007 | A1 |
| 20070238343 | Velleca | Oct 2007 | A1 |
| 20070258449 | Bennett | Nov 2007 | A1 |
| 20070274234 | Kubota | Nov 2007 | A1 |
| 20070280223 | Pan | Dec 2007 | A1 |
| 20070289017 | Copeland, III | Dec 2007 | A1 |
| 20070297406 | Rooholamini | Dec 2007 | A1 |
| 20080052487 | Akahane | Feb 2008 | A1 |
| 20080056135 | Lee | Mar 2008 | A1 |
| 20080056300 | Williams | Mar 2008 | A1 |
| 20080057918 | Abrant | Mar 2008 | A1 |
| 20080065760 | Damm | Mar 2008 | A1 |
| 20080075078 | Watanabe | Mar 2008 | A1 |
| 20080080517 | Roy | Apr 2008 | A1 |
| 20080095160 | Yadav | Apr 2008 | A1 |
| 20080101386 | Gray | May 2008 | A1 |
| 20080112133 | Torudbakken | May 2008 | A1 |
| 20080133760 | Berkvens | Jun 2008 | A1 |
| 20080159260 | Vobbilisetty | Jul 2008 | A1 |
| 20080159277 | Vobbilisetty | Jul 2008 | A1 |
| 20080165705 | Umayabashi | Jul 2008 | A1 |
| 20080172492 | Raghunath | Jul 2008 | A1 |
| 20080181196 | Regan | Jul 2008 | A1 |
| 20080186968 | Farinacci | Aug 2008 | A1 |
| 20080186981 | Seto | Aug 2008 | A1 |
| 20080205377 | Chao | Aug 2008 | A1 |
| 20080219172 | Mohan | Sep 2008 | A1 |
| 20080225852 | Raszuk | Sep 2008 | A1 |
| 20080225853 | Melman | Sep 2008 | A1 |
| 20080240129 | Elmeleegy | Oct 2008 | A1 |
| 20080253380 | Cazares | Oct 2008 | A1 |
| 20080267179 | Lavigne | Oct 2008 | A1 |
| 20080279196 | Friskney | Nov 2008 | A1 |
| 20080285458 | Lysne | Nov 2008 | A1 |
| 20080285555 | Ogasahara | Nov 2008 | A1 |
| 20080288020 | Einav | Nov 2008 | A1 |
| 20080298248 | Roeck | Dec 2008 | A1 |
| 20080304498 | Jorgensen | Dec 2008 | A1 |
| 20080304519 | Koenen | Dec 2008 | A1 |
| 20080310342 | Kruys | Dec 2008 | A1 |
| 20090022069 | Khan | Jan 2009 | A1 |
| 20090024734 | Merbach | Jan 2009 | A1 |
| 20090037607 | Farinacci | Feb 2009 | A1 |
| 20090037977 | Gai | Feb 2009 | A1 |
| 20090041046 | Hirata | Feb 2009 | A1 |
| 20090042270 | Dolly | Feb 2009 | A1 |
| 20090044270 | Shelly | Feb 2009 | A1 |
| 20090052326 | Bergamasco | Feb 2009 | A1 |
| 20090067422 | Poppe | Mar 2009 | A1 |
| 20090067442 | Killian | Mar 2009 | A1 |
| 20090079560 | Fries | Mar 2009 | A1 |
| 20090080345 | Gray | Mar 2009 | A1 |
| 20090083445 | Ganga | Mar 2009 | A1 |
| 20090092042 | Yuhara | Apr 2009 | A1 |
| 20090092043 | Lapuh | Apr 2009 | A1 |
| 20090094354 | Rastogi | Apr 2009 | A1 |
| 20090106298 | Furusho | Apr 2009 | A1 |
| 20090106405 | Mazarick | Apr 2009 | A1 |
| 20090113408 | Toeroe | Apr 2009 | A1 |
| 20090116381 | Kanda | May 2009 | A1 |
| 20090122700 | Aboba | May 2009 | A1 |
| 20090129384 | Regan | May 2009 | A1 |
| 20090129389 | Halna DeFretay | May 2009 | A1 |
| 20090138577 | Casado | May 2009 | A1 |
| 20090138752 | Graham | May 2009 | A1 |
| 20090144720 | Roush | Jun 2009 | A1 |
| 20090161584 | Guan | Jun 2009 | A1 |
| 20090161670 | Shepherd | Jun 2009 | A1 |
| 20090168647 | Holness | Jul 2009 | A1 |
| 20090199177 | Edwards | Aug 2009 | A1 |
| 20090204965 | Tanaka | Aug 2009 | A1 |
| 20090213783 | Moreton | Aug 2009 | A1 |
| 20090213867 | Devireddy | Aug 2009 | A1 |
| 20090222879 | Kostal | Sep 2009 | A1 |
| 20090225752 | Mitsumori | Sep 2009 | A1 |
| 20090232031 | Vasseur | Sep 2009 | A1 |
| 20090245112 | Okazaki | Oct 2009 | A1 |
| 20090245137 | Hares | Oct 2009 | A1 |
| 20090245242 | Carlson | Oct 2009 | A1 |
| 20090246137 | Hadida | Oct 2009 | A1 |
| 20090249444 | Macauley | Oct 2009 | A1 |
| 20090252049 | Ludwig | Oct 2009 | A1 |
| 20090252061 | Small | Oct 2009 | A1 |
| 20090252503 | Ishigami | Oct 2009 | A1 |
| 20090260083 | Szeto | Oct 2009 | A1 |
| 20090279558 | Davis | Nov 2009 | A1 |
| 20090279701 | Moisand | Nov 2009 | A1 |
| 20090292858 | Lambeth | Nov 2009 | A1 |
| 20090323698 | LeFaucheur | Dec 2009 | A1 |
| 20090323708 | Ihle | Dec 2009 | A1 |
| 20090327392 | Tripathi | Dec 2009 | A1 |
| 20090327462 | Adams | Dec 2009 | A1 |
| 20100002382 | Aybay | Jan 2010 | A1 |
| 20100027420 | Smith | Feb 2010 | A1 |
| 20100027429 | Jorgens | Feb 2010 | A1 |
| 20100042869 | Szabo | Feb 2010 | A1 |
| 20100046471 | Hattori | Feb 2010 | A1 |
| 20100054260 | Pandey | Mar 2010 | A1 |
| 20100061269 | Banerjee | Mar 2010 | A1 |
| 20100074175 | Banks | Mar 2010 | A1 |
| 20100085981 | Gupta | Apr 2010 | A1 |
| 20100097941 | Carlson | Apr 2010 | A1 |
| 20100103813 | Allan | Apr 2010 | A1 |
| 20100103939 | Carlson | Apr 2010 | A1 |
| 20100114818 | Lier | May 2010 | A1 |
| 20100131636 | Suri | May 2010 | A1 |
| 20100157844 | Casey | Jun 2010 | A1 |
| 20100158024 | Sajassi | Jun 2010 | A1 |
| 20100165877 | Shukla | Jul 2010 | A1 |
| 20100165995 | Mehta | Jul 2010 | A1 |
| 20100168467 | Johnston | Jul 2010 | A1 |
| 20100169467 | Shukla | Jul 2010 | A1 |
| 20100169948 | Budko | Jul 2010 | A1 |
| 20100182920 | Matsuoka | Jul 2010 | A1 |
| 20100189119 | Sawada | Jul 2010 | A1 |
| 20100192225 | Ma | Jul 2010 | A1 |
| 20100195489 | Zhou | Aug 2010 | A1 |
| 20100195529 | Liu | Aug 2010 | A1 |
| 20100214913 | Kompella | Aug 2010 | A1 |
| 20100215042 | Sato | Aug 2010 | A1 |
| 20100215049 | Raza | Aug 2010 | A1 |
| 20100220724 | Rabie | Sep 2010 | A1 |
| 20100226368 | Mack-Crane | Sep 2010 | A1 |
| 20100226381 | Mehta | Sep 2010 | A1 |
| 20100246388 | Gupta | Sep 2010 | A1 |
| 20100246580 | Kaganoi | Sep 2010 | A1 |
| 20100254703 | Kirkpatrick | Oct 2010 | A1 |
| 20100257263 | Casado | Oct 2010 | A1 |
| 20100258263 | Douxchamps | Oct 2010 | A1 |
| 20100265849 | Harel | Oct 2010 | A1 |
| 20100271960 | Krygowski | Oct 2010 | A1 |
| 20100272107 | Papp | Oct 2010 | A1 |
| 20100281106 | Ashwood-Smith | Nov 2010 | A1 |
| 20100284414 | Agarwal | Nov 2010 | A1 |
| 20100284418 | Gray | Nov 2010 | A1 |
| 20100284698 | McColloch | Nov 2010 | A1 |
| 20100287262 | Elzur | Nov 2010 | A1 |
| 20100287548 | Zhou | Nov 2010 | A1 |
| 20100290464 | Assarpour | Nov 2010 | A1 |
| 20100290472 | Raman | Nov 2010 | A1 |
| 20100290473 | Enduri | Nov 2010 | A1 |
| 20100299527 | Arunan | Nov 2010 | A1 |
| 20100303071 | Kotalwar | Dec 2010 | A1 |
| 20100303075 | Tripathi | Dec 2010 | A1 |
| 20100303083 | Belanger | Dec 2010 | A1 |
| 20100309820 | Rajagopalan | Dec 2010 | A1 |
| 20100309912 | Mehta | Dec 2010 | A1 |
| 20100316055 | Belanger | Dec 2010 | A1 |
| 20100329110 | Rose | Dec 2010 | A1 |
| 20100329265 | Lapuh | Dec 2010 | A1 |
| 20110007738 | Berman | Jan 2011 | A1 |
| 20110019678 | Mehta | Jan 2011 | A1 |
| 20110032945 | Mullooly | Feb 2011 | A1 |
| 20110035489 | McDaniel | Feb 2011 | A1 |
| 20110035498 | Shah | Feb 2011 | A1 |
| 20110044339 | Kotalwar | Feb 2011 | A1 |
| 20110044352 | Chaitou | Feb 2011 | A1 |
| 20110051723 | Rabie | Mar 2011 | A1 |
| 20110058547 | Waldrop | Mar 2011 | A1 |
| 20110064086 | Xiong | Mar 2011 | A1 |
| 20110064089 | Hidaka | Mar 2011 | A1 |
| 20110072208 | Gulati | Mar 2011 | A1 |
| 20110085557 | Gnanasekaran | Apr 2011 | A1 |
| 20110085560 | Chawla | Apr 2011 | A1 |
| 20110085562 | Bao | Apr 2011 | A1 |
| 20110085563 | Kotha | Apr 2011 | A1 |
| 20110088011 | Ouali | Apr 2011 | A1 |
| 20110110266 | Li | May 2011 | A1 |
| 20110134802 | Rajagopalan | Jun 2011 | A1 |
| 20110134803 | Dalvi | Jun 2011 | A1 |
| 20110134924 | Hewson | Jun 2011 | A1 |
| 20110134925 | Safrai | Jun 2011 | A1 |
| 20110142053 | Van | Jun 2011 | A1 |
| 20110142062 | Wang | Jun 2011 | A1 |
| 20110149526 | Turner | Jun 2011 | A1 |
| 20110158113 | Nanda | Jun 2011 | A1 |
| 20110161494 | McDysan | Jun 2011 | A1 |
| 20110161695 | Okita | Jun 2011 | A1 |
| 20110176412 | Stine | Jul 2011 | A1 |
| 20110188373 | Saito | Aug 2011 | A1 |
| 20110194403 | Sajassi | Aug 2011 | A1 |
| 20110194563 | Shen | Aug 2011 | A1 |
| 20110225540 | d'Entremont | Sep 2011 | A1 |
| 20110228767 | Singla | Sep 2011 | A1 |
| 20110228780 | Ashwood-Smith | Sep 2011 | A1 |
| 20110231570 | Altekar | Sep 2011 | A1 |
| 20110231574 | Saunderson | Sep 2011 | A1 |
| 20110235523 | Jha | Sep 2011 | A1 |
| 20110243133 | Villait | Oct 2011 | A9 |
| 20110243136 | Raman | Oct 2011 | A1 |
| 20110246669 | Kanada | Oct 2011 | A1 |
| 20110255538 | Srinivasan | Oct 2011 | A1 |
| 20110255540 | Mizrahi | Oct 2011 | A1 |
| 20110261828 | Smith | Oct 2011 | A1 |
| 20110268118 | Schlansker | Nov 2011 | A1 |
| 20110268120 | Vobbilisetty | Nov 2011 | A1 |
| 20110268125 | Vobbilisetty | Nov 2011 | A1 |
| 20110273988 | Tourrilhes | Nov 2011 | A1 |
| 20110273990 | Rajagopalan | Nov 2011 | A1 |
| 20110274114 | Dhar | Nov 2011 | A1 |
| 20110280572 | Vobbilisetty | Nov 2011 | A1 |
| 20110286357 | Haris | Nov 2011 | A1 |
| 20110286457 | Ee | Nov 2011 | A1 |
| 20110286462 | Kompella | Nov 2011 | A1 |
| 20110055274 | Hegge | Dec 2011 | A1 |
| 20110292947 | Vobbilisetty | Dec 2011 | A1 |
| 20110296052 | Guo | Dec 2011 | A1 |
| 20110299391 | Vobbilisetty | Dec 2011 | A1 |
| 20110299413 | Chatwani | Dec 2011 | A1 |
| 20110299414 | Yu | Dec 2011 | A1 |
| 20110299527 | Yu | Dec 2011 | A1 |
| 20110299528 | Yu | Dec 2011 | A1 |
| 20110299531 | Yu | Dec 2011 | A1 |
| 20110299532 | Yu | Dec 2011 | A1 |
| 20110299533 | Yu | Dec 2011 | A1 |
| 20110299534 | Koganti | Dec 2011 | A1 |
| 20110299535 | Vobbilisetty | Dec 2011 | A1 |
| 20110299536 | Cheng | Dec 2011 | A1 |
| 20110317559 | Kern | Dec 2011 | A1 |
| 20120011240 | Hara | Jan 2012 | A1 |
| 20120014261 | Salam | Jan 2012 | A1 |
| 20120014387 | Dunbar | Jan 2012 | A1 |
| 20120020220 | Sugita | Jan 2012 | A1 |
| 20120027017 | Rai | Feb 2012 | A1 |
| 20120033663 | Guichard | Feb 2012 | A1 |
| 20120033665 | Jacob | Feb 2012 | A1 |
| 20120033668 | Humphries | Feb 2012 | A1 |
| 20120033669 | Mohandas | Feb 2012 | A1 |
| 20120033672 | Page | Feb 2012 | A1 |
| 20120039163 | Nakajima | Feb 2012 | A1 |
| 20120042095 | Kotha | Feb 2012 | A1 |
| 20120063363 | Li | Mar 2012 | A1 |
| 20120075991 | Sugita | Mar 2012 | A1 |
| 20120099567 | Hart | Apr 2012 | A1 |
| 20120099602 | Nagapudi | Apr 2012 | A1 |
| 20120099863 | Xu | Apr 2012 | A1 |
| 20120102160 | Breh | Apr 2012 | A1 |
| 20120106339 | Mishra | May 2012 | A1 |
| 20120117438 | Shaffer | May 2012 | A1 |
| 20120131097 | Baykal | May 2012 | A1 |
| 20120131289 | Taguchi | May 2012 | A1 |
| 20120134266 | Roitshtein | May 2012 | A1 |
| 20120136999 | Roitshtein | May 2012 | A1 |
| 20120147740 | Nakash | Jun 2012 | A1 |
| 20120158997 | Hsu | Jun 2012 | A1 |
| 20120163164 | Terry | Jun 2012 | A1 |
| 20120170491 | Kern | Jul 2012 | A1 |
| 20120177039 | Berman | Jul 2012 | A1 |
| 20120210416 | Mihelich | Aug 2012 | A1 |
| 20120221636 | Surtani | Aug 2012 | A1 |
| 20120230225 | Matthews | Sep 2012 | A1 |
| 20120239918 | Huang | Sep 2012 | A1 |
| 20120243359 | Keesara | Sep 2012 | A1 |
| 20120243539 | Keesara | Sep 2012 | A1 |
| 20120250502 | Brolin | Oct 2012 | A1 |
| 20120260079 | Mruthyunjaya | Oct 2012 | A1 |
| 20120275297 | Subramanian | Nov 2012 | A1 |
| 20120275347 | Banerjee | Nov 2012 | A1 |
| 20120278804 | Narayanasamy | Nov 2012 | A1 |
| 20120281700 | Koganti | Nov 2012 | A1 |
| 20120287785 | Kamble | Nov 2012 | A1 |
| 20120294192 | Masood | Nov 2012 | A1 |
| 20120294194 | Balasubramanian | Nov 2012 | A1 |
| 20120230800 | Kamble | Dec 2012 | A1 |
| 20120320739 | Kamath | Dec 2012 | A1 |
| 20120320800 | Kamble | Dec 2012 | A1 |
| 20120327766 | Tsai et al. | Dec 2012 | A1 |
| 20130003535 | Sarwar | Jan 2013 | A1 |
| 20130003549 | Matthews | Jan 2013 | A1 |
| 20130003608 | Lei | Jan 2013 | A1 |
| 20130003737 | Sinicrope | Jan 2013 | A1 |
| 20130003738 | Koganti | Jan 2013 | A1 |
| 20130003747 | Raman | Jan 2013 | A1 |
| 20130016606 | Cirkovic | Jan 2013 | A1 |
| 20130028072 | Addanki | Jan 2013 | A1 |
| 20130034015 | Jaiswal | Feb 2013 | A1 |
| 20130034021 | Jaiswal | Feb 2013 | A1 |
| 20130034094 | Cardona | Feb 2013 | A1 |
| 20130044629 | Biswas | Feb 2013 | A1 |
| 20130058354 | Casado | Mar 2013 | A1 |
| 20130066947 | Ahmad | Mar 2013 | A1 |
| 20130067466 | Combs | Mar 2013 | A1 |
| 20130070762 | Adams | Mar 2013 | A1 |
| 20130083693 | Himura | Apr 2013 | A1 |
| 20130097345 | Munoz | Apr 2013 | A1 |
| 20130114595 | Mack-Crane et al. | May 2013 | A1 |
| 20130121142 | Bai | May 2013 | A1 |
| 20130124707 | Ananthapadmanabha | May 2013 | A1 |
| 20130124750 | Anumala | May 2013 | A1 |
| 20130127848 | Joshi | May 2013 | A1 |
| 20130132296 | Talagala | May 2013 | A1 |
| 20130135811 | Dunwoody | May 2013 | A1 |
| 20130136123 | Ge | May 2013 | A1 |
| 20130145008 | Kannan | Jun 2013 | A1 |
| 20130148546 | Eisenhauer | Jun 2013 | A1 |
| 20130148663 | Xiong | Jun 2013 | A1 |
| 20130156425 | Kirkpatrick | Jun 2013 | A1 |
| 20130163591 | Shukla | Jun 2013 | A1 |
| 20130194914 | Agarwal | Aug 2013 | A1 |
| 20130201992 | Masaki | Aug 2013 | A1 |
| 20130215754 | Tripathi | Aug 2013 | A1 |
| 20130219473 | Schaefer | Aug 2013 | A1 |
| 20130223221 | Xu | Aug 2013 | A1 |
| 20130223438 | Tripathi | Aug 2013 | A1 |
| 20130223449 | Koganti | Aug 2013 | A1 |
| 20130238802 | Sarikaya | Sep 2013 | A1 |
| 20130250289 | Kettler | Sep 2013 | A1 |
| 20130250947 | Zheng | Sep 2013 | A1 |
| 20130250951 | Koganti | Sep 2013 | A1 |
| 20130250958 | Watanabe | Sep 2013 | A1 |
| 20130259037 | Natarajan | Oct 2013 | A1 |
| 20130259047 | Bhagavathiperumal | Oct 2013 | A1 |
| 20130266015 | Qu | Oct 2013 | A1 |
| 20130268590 | Mahadevan | Oct 2013 | A1 |
| 20130272135 | Leong | Oct 2013 | A1 |
| 20130294451 | Li | Nov 2013 | A1 |
| 20130297757 | Han | Nov 2013 | A1 |
| 20130301425 | Chandra | Nov 2013 | A1 |
| 20130301642 | Radhakrishnan | Nov 2013 | A1 |
| 20130308492 | Baphna | Nov 2013 | A1 |
| 20130308641 | Ackley | Nov 2013 | A1 |
| 20130308647 | Rosset | Nov 2013 | A1 |
| 20130315125 | Ravishankar | Nov 2013 | A1 |
| 20130315246 | Zhang | Nov 2013 | A1 |
| 20130315586 | Kipp | Nov 2013 | A1 |
| 20130322427 | Stiekes | Dec 2013 | A1 |
| 20130329605 | Nakil | Dec 2013 | A1 |
| 20130332660 | Talagala | Dec 2013 | A1 |
| 20130336104 | Talla | Dec 2013 | A1 |
| 20130346583 | Low | Dec 2013 | A1 |
| 20140010239 | Xu | Jan 2014 | A1 |
| 20140013324 | Zhang | Jan 2014 | A1 |
| 20140019608 | Kawakami | Jan 2014 | A1 |
| 20140019639 | Ueno | Jan 2014 | A1 |
| 20140025736 | Wang | Jan 2014 | A1 |
| 20140029412 | Janardhanan | Jan 2014 | A1 |
| 20140029419 | Jain | Jan 2014 | A1 |
| 20140044126 | Sabhanatarajan | Feb 2014 | A1 |
| 20140050223 | Foo | Feb 2014 | A1 |
| 20140056298 | Vobbilisetty | Feb 2014 | A1 |
| 20140059225 | Gasparakis | Feb 2014 | A1 |
| 20140064056 | Sakata | Mar 2014 | A1 |
| 20140071987 | Janardhanan | Mar 2014 | A1 |
| 20140086253 | Yong | Mar 2014 | A1 |
| 20140092738 | Grandhi | Apr 2014 | A1 |
| 20140105034 | Huawei | Apr 2014 | A1 |
| 20140112122 | Kapadia | Apr 2014 | A1 |
| 20140140243 | Ashwood-Smith | May 2014 | A1 |
| 20140157251 | Hocker | Jun 2014 | A1 |
| 20140169368 | Grover | Jun 2014 | A1 |
| 20140188996 | Lie | Jul 2014 | A1 |
| 20140192804 | Ghanwani | Jul 2014 | A1 |
| 20140195694 | Sait | Jul 2014 | A1 |
| 20140195695 | Okita | Jul 2014 | A1 |
| 20140198656 | Venkatesh | Jul 2014 | A1 |
| 20140211607 | Li | Jul 2014 | A1 |
| 20140241147 | Rajagopalan | Aug 2014 | A1 |
| 20140258446 | Bursell | Sep 2014 | A1 |
| 20140269701 | Kaushik | Sep 2014 | A1 |
| 20140269709 | Benny | Sep 2014 | A1 |
| 20140269720 | Arvindinivasan | Sep 2014 | A1 |
| 20140269733 | Venkatesh | Sep 2014 | A1 |
| 20140298091 | Carlen | Oct 2014 | A1 |
| 20140348168 | Singh | Nov 2014 | A1 |
| 20140355477 | Moopath | Dec 2014 | A1 |
| 20140362854 | Addanki | Dec 2014 | A1 |
| 20140362859 | Addanki | Dec 2014 | A1 |
| 20140376550 | Khan | Dec 2014 | A1 |
| 20150009992 | Zhang | Jan 2015 | A1 |
| 20150010007 | Matsuhira | Jan 2015 | A1 |
| 20150016300 | Devireddy | Jan 2015 | A1 |
| 20150030031 | Zhou | Jan 2015 | A1 |
| 20150092593 | Kompella | Apr 2015 | A1 |
| 20150103826 | Davis | Apr 2015 | A1 |
| 20150110105 | Kapur | Apr 2015 | A1 |
| 20150110111 | Song | Apr 2015 | A1 |
| 20150110487 | Fenkes | Apr 2015 | A1 |
| 20150117256 | Sabaa | Apr 2015 | A1 |
| 20150117454 | Koponen | Apr 2015 | A1 |
| 20150124837 | Saltsidis | May 2015 | A1 |
| 20150127618 | Alberti | May 2015 | A1 |
| 20150139037 | Li | May 2015 | A1 |
| 20150139234 | Hu | May 2015 | A1 |
| 20150143369 | Zheng | May 2015 | A1 |
| 20150172098 | Agarwal | Jun 2015 | A1 |
| 20150188753 | Anumala | Jul 2015 | A1 |
| 20150188770 | Naiksatam | Jul 2015 | A1 |
| 20150195093 | Ramasubramani | Jul 2015 | A1 |
| 20150222506 | Kizhakkiniyil | Aug 2015 | A1 |
| 20150248298 | Gavrilov | Sep 2015 | A1 |
| 20150263897 | Ganichev | Sep 2015 | A1 |
| 20150263899 | Tubaltsev | Sep 2015 | A1 |
| 20150263991 | MacChiano | Sep 2015 | A1 |
| 20150271088 | Ao | Sep 2015 | A1 |
| 20150281066 | Koley | Oct 2015 | A1 |
| 20150301901 | Rath | Oct 2015 | A1 |
| 20150347468 | Bester | Dec 2015 | A1 |
| 20150365320 | Xu | Dec 2015 | A1 |
| 20160072899 | Tung | Mar 2016 | A1 |
| 20160087885 | Tripathi | Mar 2016 | A1 |
| 20160139939 | Bosch | May 2016 | A1 |
| 20160182458 | Shatzkamer | Jun 2016 | A1 |
| 20160212040 | Bhagavathiperumal | Jul 2016 | A1 |
| 20160344640 | Derlund | Nov 2016 | A1 |
| 20170012880 | Yang | Jan 2017 | A1 |
| 20170026197 | Venkatesh | Jan 2017 | A1 |
| 20170097841 | Chang | Apr 2017 | A1 |
| 20180013614 | Vobbilisetty | Jan 2018 | A1 |
| Number | Date | Country |
|---|---|---|
| 1735062 | Feb 2006 | CN |
| 1777149 | May 2006 | CN |
| 101064682 | Oct 2007 | CN |
| 101459618 | Jun 2009 | CN |
| 101471899 | Jul 2009 | CN |
| 101548511 | Sep 2009 | CN |
| 101645880 | Feb 2010 | CN |
| 102098237 | Jun 2011 | CN |
| 102148749 | Aug 2011 | CN |
| 102301663 | Dec 2011 | CN |
| 102349268 | Feb 2012 | CN |
| 102378176 | Mar 2012 | CN |
| 102404181 | Apr 2012 | CN |
| 102415065 | Apr 2012 | CN |
| 102415065 | Apr 2012 | CN |
| 102801599 | Nov 2012 | CN |
| 102801599 | Nov 2012 | CN |
| 102088388 | Apr 2014 | CN |
| 0579567 | May 1993 | EP |
| 0579567 | Jan 1994 | EP |
| 0993156 | Apr 2000 | EP |
| 0993156 | Dec 2000 | EP |
| 1398920 | Mar 2004 | EP |
| 1398920 | Mar 2004 | EP |
| 2001167 | Aug 2007 | EP |
| 1916807 | Apr 2008 | EP |
| 2854352 | Apr 2015 | EP |
| 2874359 | May 2015 | EP |
| 2008056838 | May 2008 | WO |
| 2009042919 | Apr 2009 | WO |
| 2010111142 | Sep 2010 | WO |
| 2010111142 | Sep 2010 | WO |
| 2011132568 | Oct 2011 | WO |
| 2011140028 | Nov 2011 | WO |
| 2011140028 | Nov 2011 | WO |
| 2012033663 | Mar 2012 | WO |
| 2012093429 | Jul 2012 | WO |
| 2014031781 | Feb 2014 | WO |
| Entry |
|---|
| Mahalingam “VXLAN: A Framework for Overlaying Virtualized Layer 2 Networks over Layer 3 Networks” Oct. 17, 2013 pp. 1-22, Sections 1, 4 and 4.1. |
| Office action dated Apr. 30, 2015, U.S. Appl. No. 13/351,513, filed Jan. 17, 2012. |
| Office Action dated Apr. 1, 2015, U.S. Appl. No. 13/656,438, filed Oct. 19, 2012. |
| Office Action dated May 21, 2015, U.S. Appl. No. 13/288,822, filed Nov. 3, 2011. |
| Siamak Azodolmolky et al. “Cloud computing networking: Challenges and opportunities for innovations”, IEEE Communications Magazine, vol. 51, No. 7, Jul. 1, 2013. |
| Office action dated Jun. 8, 2015, U.S. Appl. No. 14/178,042, filed Feb. 11, 2014. |
| Office Action dated Jun. 10, 2015, U.S. Appl. No. 13/890,150, filed May 8, 2013. |
| Office Action dated Jun. 18, 2015, U.S. Appl. No. 13/098,490, filed May 2, 2011. |
| Office Action dated Jun. 16, 2015, U.S. Appl. No. 13/048,817, filed Mar. 15, 2011. |
| Open Flow Configuration and Management Protocol 1.0 (OF-Config 1.0) Dec. 23, 2011. |
| Open Flow Switch Specification Version 1.2 Dec. 5, 2011. |
| Office action dated Feb. 2, 2016, U.S. Appl. No. 13/092,460, filed Apr. 22, 2011. |
| Office Action dated Feb. 2, 2016. U.S. Appl. No. 14/154,106, filed Jan. 13, 2014. |
| Office Action dated Feb. 3, 2016, U.S. Appl. No. 13/098,490, filed May 2, 2011. |
| Office Action dated Feb. 4, 2016, U.S. Appl. No. 13/557,105, filed Jul. 24, 2012. |
| Office Action dated Feb. 11, 2016, U.S. Appl. No. 14/488,173, filed Sep. 16, 2014. |
| Office Action dated Feb. 24, 2016, U.S. Appl. No. 13/971,397, filed Aug. 20, 2013. |
| Office Action dated Feb. 24, 2016, U.S. Appl. No. 12/705,508, filed Feb. 12, 2010. |
| Office Action dated Jul. 6, 2016, U.S. Appl. No. 14/618,941, filed Feb. 10, 2015. |
| Office Action dated Jul. 20, 2016, U.S. Appl. No. 14/510,913, filed Oct. 9, 2014. |
| Office Action dated Jul. 29, 2016, U.S. Appl. No. 14/473,941, filed Aug. 29, 2014. |
| Office Action dated Jul. 28, 2016, U.S. Appl. No. 14/284,212, filed May 21, 2016. |
| Eastlake, D. et al., ‘RBridges: TRILL Header Options’, Dec. 24, 2009, pp. 1-17, TRILL Working Group. |
| Perlman, Radia et al., ‘RBridge VLAN Mapping’, TRILL Working Group, Dec. 4, 2009, pp. 1-12. |
| Touch, J. et al., ‘Transparent Interconnection of Lots of Links (TRILL): Problem and Applicability Statement’, May 2009, Network Working Group, pp. 1-17. |
| ‘RBridges: Base Protocol Specification’, IETF Draft, Perlman et al., Jun. 26, 2009. |
| Switched Virtual Networks. ‘Internetworking Moves Beyond Bridges and Routers’ Data Communications, McGraw Hill. New York, US, vol. 23, No. 12, Sep. 1, 1994 (Sep. 1, 1994), pp. 66-70,72,74, XP000462385 ISSN: 0363-6399. |
| Office Action dated Apr. 9, 2014, U.S. Appl. No. 13/092,724, filed Apr. 22, 2011. |
| Office action dated Aug. 29, 2014, U.S. Appl. No. 13/042,259, filed Mar. 7, 2011. |
| Office Action dated Mar. 14, 2014,U.S. Appl. No. 13/092,460, filed Apr. 22, 2011. |
| Office Action dated Mar. 26, 2014, U.S. Appl. No. 13/092,701, filed Apr. 22, 2011. |
| Office Action dated Apr. 9, 2014, U.S. Appl. No. 13/092,752, filed Apr. 22, 2011. |
| Office action dated Aug. 21, 2014, U.S. Appl. No. 13/184,526, filed Jul. 16, 2011. |
| Office Action dated Mar. 6, 2014, U.S. Appl. No. 13/425,238, filed Mar. 20, 2012. |
| Office Action dated Jun. 18, 2014, U.S. Appl. No. 13/440,861, filed Apr. 5, 2012. |
| Office Action dated Feb. 28, 2014, U.S. Appl. No. 13/351,513, filed Jan. 17, 2012. |
| Office Action dated May 9, 2014, U.S. Appl. No. 13/484,072, filed May 30, 2012. |
| Office Action dated May 14, 2014, U.S. Appl. No. 13/533,843, filed Jun. 26, 2012. |
| Office Action dated Feb. 20, 2014, U.S. Appl. No. 13/598,204, filed Aug. 29, 2012. |
| Office Action dated Jun. 6, 2014, U.S. Appl. No. 13/669,357, filed Nov. 5, 2012. |
| Brocade, ‘Brocade Fabrics OS (FOS) 6.2 Virtual Fabrics Feature Frequently Asked Questions’, pp. 1-6, 2009 Brocade Communications Systems, Inc. |
| Brocade, ‘FastIron and TurboIron 24x Configuration Guide’, Feb. 16, 2010. |
| Brocade, ‘The Effortless Network: Hyperedge Technology for the Campus LAN’ 2012. |
| Brocade ‘An Introduction to Brocade VCS Fabric Technology’, Dec. 3, 2012. |
| Christensen, M. et al., ‘Considerations for Internet Group Management Protocol (IGMP) and Multicast Listener Discovery (MLD) Snooping Switches’, May 2006. |
| FastIron Configuration Guide Supporting Ironware Software Release 07.0.00, Dec. 18, 2009. |
| Foundary FastIron Configuration Guide, Software Release FSX 04.2.00b, Software Release FWS 04.3.00, Software Release FGS 05.0.00a, Sep. 2008. |
| Huang, Nen-Fu et al., ‘An Effective Spanning Tree Algorithm for a Bridged LAN’, Mar. 16, 1992. |
| Knight, ‘Network Based IP VPN Architecture using Virtual Routers’, May 2003. |
| Knight P et al: ‘Layer 2 and 3 Virtual Private Networks: Taxonomy, Technology, and Standardization Efforts’, IEEE, Communications Magazine; IEEE Service Center, Piscataway, US, vol. 42, No. 6, Jun. 1, 2004 (Jun. 1, 2004), pp. 124-131, XP001198207, ISSN: 0163-6804, DOI: 1031109/MCOM.200431304248. |
| Knight S et al: ‘Virtual Router Redundancy Protocol’ Internet Citation Apr. 1, 1998 (Apr. 1, 1998), XP002135272 Retrieved from the Internet: URL:ftp://ftp.isi.edu/in-notes/rfc2338.txt [retrieved on Apr. 10, 2000]. |
| Lapuh, Roger et al., ‘Split Multi-link Trunking (SMLT)’, draft-lapuh-network-smlt-08, Jul. 2008. |
| Lapuh, Roger et al., ‘Split Multi-Link Trunking (SMLT)’, Network Working Group, Oct. 2012. |
| Louati, Wajdi et al., ‘Network-based virtual personal overlay networks using programmable virtual routers’, IEEE Communications Magazine, Jul. 2005. |
| Narten, T. et al., ‘Problem Statement: Overlays for Network Virtualization d raft-narten-n vo3-over l ay-problem-statement-01’, Oct. 31, 2011. |
| Office Action for U.S. Appl. No. 13/042,259, filed Mar. 7, 2011, from Jaroenchonwanit, Bunjob, dated Jan. 16, 2014. |
| Office Action for U.S. Appl. No. 13/092,752, filed Apr. 22, 2011, from Park, Jung H., dated Jul. 18, 2013. |
| Office Action for U.S. Appl. No. 13/365,993, filed Feb. 3, 2012, from Cho, Hong Sol., dated Jul. 23, 2013. |
| Office Action for U.S. Appl. No. 12/725,249, filed Mar. 16, 2010, dated Apr. 26, 2013. |
| Office Action for U.S. Appl. No. 12/725,249, filed Mar. 16, 2010, dated Sep. 12, 2012. |
| Office Action for U.S. Appl. No. 12/950,968, filed Nov. 19, 2010, dated Jan. 4, 2013. |
| Office Action for U.S. Appl. No. 12/950,968, filed Nov. 19, 2010, dated Jun. 7, 2012. |
| Office Action for U.S. Appl. No. 12/950,974, filed Nov. 19, 2010, dated Dec. 20, 2012. |
| Office Action for U.S. Appl. No. 12/950,974, filed Nov. 19, 2010, dated May 24, 2012. |
| Office Action for U.S. Appl. No. 13/030,688, filed Feb. 18, 2011, dated Apr. 25, 2013. |
| Office Action for U.S. Appl. No. 13/030,806, filed Feb. 18, 2011, dated Dec. 3, 2012. |
| Office Action for U.S. Appl. No. 13/030,806, filed Feb. 18, 2011, dated Jun. 11, 2013. |
| Office Action for U.S. Appl. No. 13/042,259, filed Mar. 7, 2011, dated Mar. 18, 2013. |
| Office Action for U.S. Appl. No. 13/042,259, filed Mar. 7, 2011, dated Jul. 31, 2013. |
| Office Action for U.S. Appl. No. 13/044,301, filed Mar. 9, 2011, dated Feb. 22, 2013. |
| Office Action for U.S. Appl. No. 13/044,301, filed Mar. 9, 2011, dated Jun. 11, 2013. |
| Office Action for U.S. Appl. No. 13/044,326, filed Mar. 9, 2011, dated Oct. 2, 2013. |
| Office Action for U.S. Appl. No. 13/050,102, filed Mar. 17, 2011, dated Oct. 26, 2012. |
| Office Action for U.S. Appl. No. 13/050,102, filed Mar. 17, 2011, dated May 16, 2013. |
| Office Action for U.S. Appl. No. 13/087,239, filed Apr. 14, 2011, dated May 22, 2013. |
| Office Action for U.S. Appl. No. 13/092,460, filed Apr. 22, 2011, dated Jun. 21, 2013. |
| Office Action for U.S. Appl. No. 13/092,580, filed Apr. 22, 2011, dated Jun. 10, 2013. |
| Office Action for U.S. Appl. No. 13/092,701, filed Apr. 22, 2011, dated Jan. 28, 2013. |
| Office Action for U.S. Appl. No. 13/092,701, filed Apr. 22, 2011, dated Jul. 3, 2013. |
| Office Action for U.S. Appl. No. 13/092,724, filed Apr. 22, 2011, dated Feb. 5, 2013. |
| Office Action for U.S. Appl. No. 13/092,724, filed Apr. 22, 2011, dated Jul. 16, 2013. |
| Office Action for U.S. Appl. No. 13/092,752, filed Apr. 22, 2011, dated Feb. 5, 2013. |
| Office Action for U.S. Appl. No. 13/092,864, filed Apr. 22, 2011, dated Sep. 19, 2012. |
| Office Action for U.S. Appl. No. 13/092,873, filed Apr. 22, 2011, dated Jun. 19, 2013. |
| Office Action for U.S. Appl. No. 13/092,877, filed Apr. 22, 2011, dated Mar. 4, 2013. |
| Office Action for U.S. Appl. No. 13/092,877, filed Apr. 22, 2011, dated Sep. 5, 2013. |
| Office Action for U.S. Appl. No. 13/098,360, filed Apr. 29, 2011, dated May 31, 2013. |
| Office Action for U.S. Appl. No. 13/098,490, filed May 2, 2011, dated Dec. 21, 2012. |
| Office Action for U.S. Appl. No. 13/098,490, filed May 2, 2011, dated Mar. 27, 2014. |
| Office Action for U.S. Appl. No. 13/098,490, filed May 2, 2011, dated Jul. 9, 2013. |
| Office Action for U.S. Appl. No. 13/184,526, filed Jul. 16, 2011, dated Jan. 28, 2013. |
| Office Action for U.S. Appl. No. 13/184,526, filed Jul. 16, 2011, dated May 22, 2013. |
| Office Action for U.S. Appl. No. 13/312,903, filed Dec. 6, 2011, dated Jun. 13, 2013. |
| Office Action for U.S. Appl. No. 13/092,873, filed Apr. 22, 2011, dated Nov. 29, 2013. |
| Office Action for U.S. Appl. No. 13/184,526, filed Jul. 16, 2011, dated Dec. 2, 2013. |
| Office Action for U.S. Appl. No. 13/533,843, filed Jun. 26, 2012, dated Oct. 21, 2013. |
| Office Action for U.S. Appl. No. 13/598,204, filed Aug. 29, 2012, dated Feb. 20, 2014. |
| Perlman, Radia et al., ‘Challenges and Opportunities in the Design of TRILL: a Routed layer 2 Technology’, 2009. |
| Perlman, Radia et al., ‘RBridges: Base Protocol Specification; Draft-ietf-trill-rbridge-protocol-16.txt’, Mar. 3, 2010, pp. 1-117. |
| S. Nadas et al., ‘Virtual Router Redundancy Protocol (VRRP) Version 3 for IPv4 and IPv6’, Internet Engineering Task Force, Mar. 2010. |
| Zhai F. Hu et al. ‘RBridge: Pseudo-Nickname; draft-hu-trill-pseudonode-nickname-02.txt’, May 15, 2012. |
| ‘An Introduction to Brocade VCS Fabric Technology’, BROCADE white paper, http://community.brocade.com/docs/DOC-2954, Dec. 3, 2012. |
| U.S. Appl. No. 13/030,806 Office Action dated Dec. 3, 2012. |
| Office action dated Jan. 10, 2014, U.S. Appl. No. 13/092,580, filed Apr. 22, 2011. |
| Office action dated Jan. 16, 2014, U.S. Appl. No. 13/042,259, filed Mar. 7, 2011. |
| Office action dated Jul. 31, 2013, U.S. Appl. No. 13/042,259, filed Mar. 7, 2011. |
| Office action dated Jan. 6, 2014, U.S. Appl. No. 13/092,877, filed Apr. 22, 2011. |
| Office action dated Oct. 2, 2013, U.S. Appl. No. 13/044,326, filed Mar. 9, 2011. |
| Office action dated Dec. 2, 2013, U.S. Appl. No. 13/184,526, filed Jul. 16, 2011. |
| Office action dated Nov. 29, 2013, U.S. Appl. No. 13/092,873, filed Apr. 22, 2011. |
| Office action dated Nov. 12, 2013, U.S. Appl. No. 13/312,903, filed Dec. 6, 2011. |
| Brocade ‘Brocade Unveils ‘The Effortless Network’’, http://newsroom.brocade.com/press-releases/brocade-unveils-the-effortless-network-nasdaq-brcd-0859535, 2012. |
| Kreeger, L. et al., ‘Network Virtualization Overlay Control Protocol Requirements draft-kreeger-nvo3-overlay-cp-00’, Jan. 30, 2012. |
| Office Action for U.S. Appl. No. 13/365,808, filed Jul. 18, 2013, dated Jul. 18, 2013. |
| Office Action for U.S. Appl. No. 13/092,887 dated Jan. 6, 2014. |
| Office action dated Apr. 26, 2012, U.S. Appl. No. 12/725,249, filed Mar. 16, 2010. |
| Office action dated Sep. 12, 2012, U.S. Appl. No. 12/725,249, filed Mar. 16, 2010. |
| Office action dated Dec. 21, 2012, U.S. Appl. No. 13/098,490, filed May 2, 2011. |
| Office action dated Mar. 27, 2014, U.S. Appl. No. 13/098,490, filed May 2, 2011. |
| Office action dated Jul. 9, 2013, U.S. Appl. No. 13/098,490, filed May 2, 2011. |
| Office action dated May 22, 2013, U.S. Appl. No. 13/087,239, filed Apr. 14, 2011. |
| Office action dated Dec. 5, 2012, U.S. Appl. No. 13/087,239, filed Apr. 14, 2011. |
| Office action dated Feb. 5, 2013, U.S. Appl. No. 13/092,724, filed Apr. 22, 2011. |
| Office action dated Jun. 10, 2013, U.S. Appl. No. 13/092,580, filed Apr. 22, 2011. |
| Office action dated Mar. 18, 2013, U.S. Appl. No. 13/040,2259, filed Mar. 7, 2011. |
| Office action dated Jun. 21, 2013, U.S. Appl. No. 13/092,460, filed Apr. 22, 2011. |
| Office action dated Jan. 28, 2013, U.S. Appl. No. 13/092,701, filed Apr. 22, 2011. |
| Office action dated Jul. 3, 2013, U.S. Appl. No. 13/092,701, filed Apr. 22, 2011. |
| Office action dated Jul. 18, 2013, U.S. Appl. No. 13/092,752, filed Apr. 22, 2011. |
| Office action dated Dec. 20, 2012, U.S. Appl. No. 12/950,974, filed Nov. 19, 2010. |
| Office action dated May 24, 2012, U.S. Appl. No. 12/950,974, filed Nov. 19, 2010. |
| Office action dated Sep. 5, 2013, U.S. Appl. No. 13/092,877, filed Apr. 22, 2011. |
| Office action dated Mar. 4, 2013, U.S. Appl. No. 13/092,877, filed Apr. 22, 2011. |
| Office action dated Jan. 4, 2013, U.S. Appl. No. 12/950,968, filed Nov. 19, 2010. |
| Office action dated Jun. 7, 2012, U.S. Appl. No. 12/950,968, filed Nov. 19, 2010. |
| Office action dated Sep. 19, 2012, U.S. Appl. No. 13/092,864, filed Apr. 22, 2011. |
| Office action dated May 31, 2013, U.S. Appl. No. 13/098,360, filed Apr. 29, 2011. |
| Office action dated Dec. 3, 2012, U.S. Appl. No. 13/030,806, filed Feb. 18, 2011. |
| Office action dated Apr. 22, 2014, U.S. Appl. No. 13/030,806, filed Feb. 18, 2011. |
| Office action dated Jun. 11, 2013, U.S. Appl. No. 13/030,806, filed Feb. 18, 2011. |
| Office action dated Apr. 25, 2013, U.S. Appl. No. 13/030,688, filed Feb. 18, 2011. |
| Office action dated Feb. 22, 2013, U.S. Appl. No. 13/044,301, filed Mar. 9, 2011. |
| Office action dated Jun. 11, 2013, U.S. Appl. No. 13/044,301, filed Mar. 9, 2011. |
| Office action dated Oct. 26, 2012, U.S. Appl. No. 13/050,102, filed Mar. 17, 2011. |
| Office action dated May 16, 2013, U.S. Appl. No. 13/050,102, filed Mar. 17, 2011. |
| Office action dated Aug. 4, 2014, U.S. Appl. No. 13/050,102, filed Mar. 17, 2011. |
| Office action dated Jan. 28, 2013, U.S. Appl. No. 13/148,526, filed Jul. 16, 2011. |
| Office action dated May 22, 2013, U.S. Appl. No. 13/148,526, filed Jul. 16, 2011. |
| Office action dated Jun. 19, 2013, U.S. Appl. No. 13/092,873, filed Apr. 22, 2011. |
| Office action dated Jul. 18, 2013, U.S. Appl. No. 13/365,808, filed Feb. 3, 2012. |
| Office action dated Jun. 13, 2013, U.S. Appl. No. 13/312,903, filed Dec. 6, 2011. |
| Lapuh, Roger et al., ‘Split Multi-link Trunking (SMLT) draft-lapuh-network-smlt-08’, Jan. 2009. |
| Office Action for U.S. Appl. No. 13/030,688, filed Feb. 18, 2011, dated Jul. 17, 2014. |
| Office Action for U.S. Appl. No. 13/044,326, filed Mar. 9, 2011, dated Jul. 7, 2014. |
| Office Action for U.S. Appl. No. 13/092,752, filed Apr. 22, 2011, dated Apr. 9, 2014. |
| Office Action for U.S. Appl. No. 13/092,873, filed Apr. 22, 2011, dated Jul. 25, 2014. |
| Office Action for U.S. Appl. No. 13/092,877, filed Apr. 22, 2011, dated Jun. 20, 2014. |
| Office Action for U.S. Appl. No. 13/312,903, filed Dec. 6, 2011, dated Aug. 7, 2014. |
| Office Action for U.S. Appl. No. 13/351,513, filed Jan. 17, 2012, dated Jul. 24, 2014. |
| Office Action for U.S. Appl. No. 13/425,238, filed Mar. 20, 2012, dated Mar. 6, 2014. |
| Office Action for U.S. Appl. No. 13/556,061, filed Jul. 23, 2012, dated Jun. 6, 2014. |
| Office Action for U.S. Appl. No. 13/742,207 dated Jul. 24, 2014, filed Jan. 15, 2013. |
| Office Action for U.S. Appl. No. 13/950,974, filed Nov. 19, 2010, from Haile, Awet A., dated Dec. 2, 2012. |
| Office Action for U.S. Appl. No. 13/087,239, filed Apr. 14, 2011, dated Dec. 5, 2012. |
| Office Action for U.S. Appl. No. 13/351,513, filed Jan. 17, 2012, dated Feb. 28, 2014. |
| Perlman R: ‘Challenges and opportunities in the design of TRILL: a routed layer 2 technology’, 2009 IEEE Globecom Workshops, Honolulu, HI, USA, Piscataway, NJ, USA, Nov. 30, 2009 (Nov. 30, 2009), pp. 1-6, XP002649647, DOI: 10.1109/GLOBECOM.2009.5360776 ISBN: 1-4244-5626-0 [retrieved on Jul. 19, 2011]. |
| TRILL Working Group Internet-Draft Intended status: Proposed Standard RBridges: Base Protocol Specificaiton Mar. 3, 2010. |
| Office action dated Aug. 14, 2014, U.S. Appl. No. 13/092,460, filed Apr. 22, 2011. |
| Office action dated Jul. 7, 2014, for U.S. Appl. No. 13/044,326, filed Mar. 9, 2011. |
| Office Action dated Dec. 19, 2014, for U.S. Appl. No. 13/044,326, filed Mar. 9, 2011. |
| Office Action for U.S. Appl. No. 13/092,873, filed Apr. 22, 2011, dated Nov. 7, 2014. |
| Office Action for U.S. Appl. No. 13/092,877, filed Apr. 22, 2011, dated Nov. 10, 2014. |
| Office Action for U.S. Appl. No. 13/157,942, filed Jun. 10, 2011. |
| Mckeown, Nick et al. “OpenFlow: Enabling Innovation in Campus Networks”, Mar. 14, 2008, www.openflow.org/documents/openflow-wp-latest.pdf. |
| Office Action for U.S. Appl. No. 13/044,301, dated Mar. 9, 2011. |
| Office Action for U.S. Appl. No. 13/184,526, filed Jul. 16, 2011, dated Jan. 5, 2015. |
| Office Action for U.S. Appl. No. 13/598,204, filed Aug. 29, 2012, dated Jan. 5, 2015. |
| Office Action for U.S. Appl. No. 13/669,357, filed Nov. 5, 2012, dated Jan. 30, 2015. |
| Office Action for U.S. Appl. No. 13/851,026, filed Mar. 26, 2013, dated Jan. 30, 2015. |
| Office Action for U.S. Appl. No. 13/786,328, filed Mar. 5, 2013, dated Mar. 13, 2015. |
| Office Action for U.S. Appl. No. 13/092,460, filed Apr. 22, 2011, dated Mar. 13, 2015. |
| Office Action for U.S. Appl. No. 13/425,238, dated Mar. 12, 2015. |
| Office Action for U.S. Appl. No. 13/092,752, filed Apr. 22, 2011, dated Feb. 27, 2015. |
| Office Action for U.S. Appl. No. 13/042,259, filed Mar. 7, 2011, dated Feb. 23, 2015. |
| Office Action for U.S. Appl. No. 13/044,301, filed Mar. 9, 2011, dated Jan. 29, 2015. |
| Office Action for U.S. Appl. No. 13/050,102, filed Mar. 17, 2011, dated Jan. 26, 2015. |
| Rosen, E. et al., “BGP/MPLS VPNs”, Mar. 1999. |
| Office Action for U.S. Appl. No. 14/577,785, filed Dec. 19, 2014, dated Apr. 13, 2015. |
| Office Action for U.S. Appl. No. 13/425,238, filed Mar. 20, 2012, dated Mar. 12, 2015. |
| Abawajy J. “An Approach to Support a Single Service Provider Address Image for Wide Area Networks Environment” Centre for Parallel and Distributed Computing, School of Computer Science Carleton University, Ottawa, Ontario, K1S 5B6, Canada. |
| Office Action dated Jan. 31, 2017, U.S. Appl. No. 13/184,526, filed Jul. 16, 2011. |
| Office Action dated Jan. 27, 2017, U.S. Appl. No. 14/216,292, filed Mar. 17, 2014. |
| Office Action dated Jan. 26, 2017, U.S. Appl. No. 13/786,328, filed Mar. 5, 2013. |
| Office Action dated Dec. 2, 2016, U.S. Appl No. 14/512,268, filed Oct. 10, 2014. |
| Office Action dated Dec. 1, 2016, U.S. Appl. No. 13/899,849, filed May 22, 2013. |
| Office Action dated Dec. 1, 2016, U.S. Appl. No. 13/656,438, filed Oct. 19, 2012. |
| Office Action dated Nov. 30, 2016, U.S. Appl. No. 13/598,204, filed Aug. 29, 2012. |
| Office Action dated Nov. 21, 2016, U.S. Appl. No. 13/669,357, filed Nov. 5, 2012. |
| Office Action dated Feb. 8, 2017, U.S. Appl. No. 14/473,941, filed Aug. 29, 2014. |
| Office Action dated Feb. 8, 2017, U.S. Appl. No. 14/822,380, filed Aug. 10, 2015. |
| Office Action dated 06/18/215, U.S. Appl. No. 13/098,490, filed May 2, 2011. |
| Office Action dated Jul. 31, 2015, U.S. Appl. No. 13/598,204, filed Aug. 29, 2014. |
| Office Action dated Jul. 31, 2015, U.S. Appl. No. 14/473,941, filed Aug. 29, 2014. |
| Office Action dated Jul. 31, 2015, U.S. Appl. No. 14/488,173, filed Sep. 16, 2014. |
| Office Action dated Aug. 21, 2015, U.S. Appl. No. 13/776,217, filed Feb. 25, 2013. |
| Office Action dated Aug. 19, 2015, U.S. Appl. No. 14/156,374, filed Jan. 15, 2014. |
| Office Action dated Sep. 2, 2015, U.S. Appl. No. 14/151,693, filed Jan. 9, 2014. |
| Office Action dated Sep. 17, 2015, U.S. Appl. No. 14/577,785, filed Dec. 19, 2014. |
| Office Action dated Sep. 22, 2015 U.S. Appl. No. 13/656,438, filed Oct. 19, 2012. |
| Office Action dated Nov. 5, 2015, U.S. Appl. No. 14/178,042, filed Feb. 11, 2014. |
| Office Action dated Oct. 19, 2015, U.S. Appl. No. 14/215,996, filed Mar. 17, 2014. |
| Office Action dated Sep. 18, 2015, U.S. Appl. No. 13/345,566, filed Jan. 6, 2012. |
| Office Action dated Jun. 13, 2018, U.S. Appl. No. 13/786,328, filed Mar. 5, 2013. |
| IEEE et al., “Amendment to Carrier Sense Multiple Access with Collision Detection (CSMA/CD) Access Method and Physical Layer Specifications—Aggregation of Multiple Link Segments”, Mar. 30, 2000, IEEE Computer Society, IEEE Std 802.3ad-2000, pp. 116-117. |
| Office Action dated Jul. 13, 2018, U.S. Appl. No. 15/402,924, filed Jul. 13, 2018. |
| Office Action dated Jul. 24, 2018, U.S. Appl. No. 14/799,371, filed Jul. 24, 2018. |
| Office Action for U.S. Appl. No. 14/216,292, dated Oct. 6, 2017. |
| Office Action dated Oct. 25, 2017, U.S. Appl. No. 14/867,865, filed Sep. 28, 2015. |
| Office action dated Oct. 26, 2017, U.S. Appl. No. 14/817,097, filed Aug. 3, 2015. |
| Office Action dated Mar. 20, 2018, U.S. Appl. No. 14/867,865, filed Sep. 28, 2015. |
| Office Action for U.S. Appl. No. 14/817,097 dated May 4, 2017. |
| Office Action for U.S. Appl. No. 14/872,966, dated Apr. 20, 2017. |
| Office Action for U.S. Appl. No. 14/680,915, dated May 3, 2017. |
| Office Action for U.S. Appl. No. 14/792,166, dated Apr. 26, 2017. |
| Office Action for U.S. Appl. No. 14/510, 913, dated Jun. 30, 2017. |
| Office Action for U.S. Appl. No. 15/005,946, dated Jul. 14, 2017. |
| Office Action for U.S. Appl. No. 13/092,873, dated Jul. 19, 2017. |
| Office Action for U.S. Appl. No. 15/047,539, dated Aug. 7, 2017. |
| Office Action for U.S. Appl. No. 14/830,035, dated Aug. 28, 2017. |
| Office Action for U.S. Appl. No. 13/098,490, dated Aug. 24, 2017. |
| Office Action for U.S. Appl. No. 13/786,328, dated Aug. 21, 2017. |
| Office Action for U.S. Appl. No. 14/660,803, dated May 17, 2017. |
| Office Action for U.S. Appl. No. 14/488,173, dated May 12, 2017. |
| Office Action for U.S. Appl. No. 13/288,822, dated May 26, 2017. |
| Office Action for U.S. Appl. No. 14/329,447, dated Jun. 8, 2017. |
| “Network based IP VPN Architecture using Virtual Routers” Paul Knight et al. |
| Yang Yu et al “A Framework of using OpenFlow to handle transient link failure”, TMEE, 2011 International Conference on, IEEE, Dec. 16, 2011. |
| Office Action for U.S. Appl. No. 15/227,789, dated Feb. 27, 2017. |
| Office Action for U.S. Appl. No. 14/822,380, dated Feb. 8, 2017. |
| Office Action for U.S. Appl. No. 14/704,660, dated Feb. 27, 2017. |
| Office Action for U.S. Appl. No. 14/510,913, dated Mar. 3, 2017. |
| Office Action for U.S. Appl. No. 14/473,941, dated Feb. 8, 2017. |
| Office Action for U.S. Appl. No. 14/329,447, dated Feb. 10, 2017. |
| Office Action for U.S. Appl. No. 14/662,095, dated Mar. 24, 2017. |
| Office Action for U.S. Appl. No. 15/005,967, dated Mar. 31, 2017. |
| Office Action for U.S. Appl. No. 15/215,377, dated Apr. 7, 2017. |
| Office Action for U.S. Appl. No. 13/098,490, dated Apr. 6, 2017. |
| Office Action for U.S. Appl. No., 14/662,092, dated Mar. 29. 2017. |
| Number | Date | Country | |
|---|---|---|---|
| 20150271104 A1 | Sep 2015 | US |
| Number | Date | Country | |
|---|---|---|---|
| 61968141 | Mar 2014 | US |
