Patent Application
20190335539
The present embodiments relate to wireless network deployments. In particular, the present embodiments relate to hybrid channel wireless devices and systems.
In computer networking, a wireless access point (WAP), or more generally just access point (AP), is a networking hardware device that allows a Wi-Fi® device to connect to a wired network. The AP usually connects to a router or controller (via a wired network) as a standalone device, but it can also be an integral component of the router or controller itself. The AP communicates with other client devices (clients) via wireless signals transmitted and received through a radio antenna system.
A system embodiment may include: a first hybrid access point of one or more hybrid access points, the first hybrid access point comprising: an Ethernet port, the Ethernet port connecting the hybrid access point to one or more connected devices, where the Ethernet port may be associated with an Ethernet-based media access control (MAC) address; one or more physical radios, where each of the one or more physical radios may be configured to transmit and receive wireless signals between the hybrid access point and one or more user devices; one or more virtual access points (VAPs) configured by the one or more physical radios, where the one or more VAPs may include: at least one VAP configured to utilize a MAC layer of a multi-channel architecture (MCA); and at least one VAP configured to utilize a MAC layer of a channel blanket single-channel architecture (SCA); a bridge, where the bridge may connect each VAP to the hybrid access point Ethernet port via the Ethernet-based MAC address.
Additional system embodiments may include: a second hybrid access point of the one or more hybrid access points; and a wireless controller, where the wireless controller may be in communication with the first hybrid access point and the second hybrid access point. In additional system embodiments, the wireless controller may configure the first hybrid access point by transmitting a first configuration file to the first hybrid access point, where the wireless controller may configure the second hybrid access point by transmitting a second configuration file to the second hybrid access point, and where the first configuration file and the second configuration file may be generated in response to an input by a user regarding the specifications of a desired wireless network deployment.
In additional system embodiments, the first hybrid access point and the second hybrid access point may provide both SCA wireless signals and MCA wireless signals. In additional system embodiments, the first hybrid access point and the second hybrid access point may form a wireless local area network (WLAN). In additional system embodiments, the one or more physical radios may be WLAN radios. In additional system embodiments, the wireless controller may be connected to the first hybrid access point and the second hybrid access point via one or more physical Ethernet cables.
In additional system embodiments, the at least one VAP configured to utilize the MAC layer of the SCA in the first hybrid access point may include a first basic service set identifier (BSSID), and where at least one VAP configured to utilize a MAC layer of the SCA in the second hybrid access point may include the first BSSID. In additional system embodiments, the at least one VAP configured to utilize the MAC layer of the channel blanket SCA may further include a first SCA station database. In additional system embodiments, the first SCA station database may contain data on user devices of the one or more user devices that have been allowed to communicate with the first hybrid access point. In additional system embodiments, the second hybrid access point may include a second SCA station database, where the first SCA station database may be in communication with the second SCA station database. In additional system embodiments, the first SCA station database may be in communication with the second SCA station database via a local area network (LAN) link between the first hybrid access point and the second hybrid access point. In additional system embodiments, the first SCA station database may be in communication with the second SCA station database via a wireless controller, where the wireless controller may be connected between the first hybrid access point and the second hybrid access point via an Ethernet connection.
In additional system embodiments, the at least one VAP configured to utilize the MAC layer of the MCA standard may further include an MCA station database. In additional system embodiments, the MCA station database may contain data on user devices of the one or more user devices that have been allowed to communicate with the first hybrid access point. In additional system embodiments, the MCA station database may contain data on user devices of the one or more user devices that have been allowed to communicate with an outside network.
A method embodiment may include: receiving, by a hybrid access point of one or more hybrid access points, a frame from a user device; parsing, by the hybrid access point, the received frame, wherein parsing extracts a basic service set identifier (BSSID) from a header of the frame; determining, by the hybrid access point, if the BSSID of the received frame is a multi-channel architecture (MCA) or a single-channel architecture (SCA); passing, by the hybrid access point, the received frame to an IEEE 802.11 stack for processing by the MCA if the BSSID of the received frame is MCA; and passing, by the hybrid access point, the received frame to a channel blanket stack for processing by the SCA if the BSSID of the received frame is SCA. In additional method embodiments, passing the received frame to the channel blanket stack for processing by the SCA if the BSSID if the received frame is SCA may further include: synchronizing the received frame across all of the one or more hybrid access points; determining if the received frame is a duplicate at each access point; and deleting duplicate frames where the received frame is received at two or more hybrid access points.
Another method embodiment may include: receiving, by a hybrid access point of one or more hybrid access points, a frame for transmission to a destination device; parsing, by the hybrid access point, a media access control (MAC) address of the destination device; determining, by the hybrid access point, if the frame if the frame should be passed to a multi-channel architecture (MCA) or a single-channel architecture (SCA); binding, by the hybrid access point, the frame to an MCA virtual access point (VAP) for transmission to the destination device if the frame is determined to be passed to the MCA; synchronizing, by the hybrid access point, the frame between all hybrid access points (APs) if the frame is determined to be passed to the SCA; and binding the synchronized frame to an SCA VAP for transmission to the destination device if the frame is determined to be passed to the SCA. In additional method embodiments, parsing the MAC address of the destination device may further include: comparing a MAC address of the received frame to a MAC address stored in a station database.
The various embodiments of the present hybrid channel wireless devices and systems now will be discussed in detail with an emphasis on highlighting the advantageous features. These embodiments depict the novel and non-obvious hybrid channel wireless devices and systems shown in the accompanying drawings, which are for illustrative purposes only. These drawings include the following figures, in which like numerals indicate like parts:
The following detailed description describes the present embodiments with reference to the drawings. In the drawings, reference numbers label elements of the present embodiments. These reference numbers are reproduced below in connection with the discussion of the corresponding drawing features.
The disclosed system and method relate to a hybrid wireless access point (AP) which can support both single-channel mode and multi-channel mode at same time and within the same device. Uplink and/or downlink packets may be received by the hybrid AP, where the received packet may be same packet sent to different hybrid APs, and then each hybrid AP may decide to use these received packets for single-channel architecture (SCA), multi-channel architecture (MCA), or both. In SCA, the hybrid APs may communicate with each other to sync the SCA behavior. In standard MCA, APs do not talk with each other. If a device was connected to one hybrid AP over an SCA unique basic service set identifier (BSSID), this hybrid AP may announce this device to the other hybrid APs so that if or when the device roams to any other hybrid AP, each hybrid AP will know to consider its packets as part of SCA. All hybrid APs with a common SCA BSSID may share the same synced database of wireless stations. The packet redirecting decision may check the SCA database for the MAC address and if they are not there then the packet may be for MCA. Each hybrid AP may have a fixed number of physical devices, such as wireless radios, and many virtual devices refer to as Virtual Access Points (VAPs). Each VAP may be bounded to a radio and have a unique MAC address. In SCA, this address is mutual to VAPs on all APs while in MCA it must be different. By utilizing both SCA and MCA on a single hybrid AP, both SCA and MCA may be utilized without the need for dual and non-connected devices. For example, if ten APs were needed to cover an area, existing systems would require ten SCA APs and ten MCA APs for a total of twenty APs. By contrast, the system disclosed herein would only require ten hybrid APs with the ten hybrid APs in communication with one another.
There are different technologies that can solve a variety of scenarios in enterprise wireless deployment situations. Typically, a customer has had to choose the solution that better fits their needs or instead install several deployments for different scenarios. For example, 802.11k/r/v is considered a standard to provide seamless roaming in multi-channel architecture. However, new standards can require that the protocol is supported by both the wireless access points and wireless stations. Some client devices, such as smartphones and/or laptops support this protocol currently, but many Internet of Things (IoT) devices do not support this protocol. Therefore, a customer deploying wireless systems would have to make a big effort to adjust all the connected stations rather than supporting both architectures in order to give a seamless roaming solution for all types of stations. One option is to have a single multiple-channel architecture (MCA) deployment with 802.11k/r/v to service supported devices and to add an additional single-channel architecture (SCA) deployment for legacy devices. In this way, customers can enjoy the benefits of standard deployment but still support legacy devices over large areas.
Current wireless equipment works either in single-channel or multi-channel architectures and customers have to make a decision on which technology to base their deployment. As each architecture type has its own benefits and downsides the customer will take a higher risk when using only a single architecture. However, when deploying both architectures, the customer can adjust each architecture to their specific usage. Deploying the two architectures would require having separate hardware for each setup which increases the price and complexity. In many embodiments of the invention, both MCA and SCA setups can coexist on the same hardware and allow almost any combination of configurations between the two architectures.
As the number of Internet of Things (IoT) devices increase in wireless networks, there is an ever-increasing requirement for supporting these IoT devices. Some traditional Wi-Fi® stations such as, but not limited to, laptop and desktop computers require high throughput and roaming is not the biggest concern, making these client devices more suitable for MCA architectures. Other devices such as robots, sensors, and Voice over Internet Protocol (VoIP) devices typically require seamless mobility but do not often require much data throughput, making them more suitable for SCA architectures. As the benefits of single-channel and multi-channel are different, the disclosed system and method utilizes the benefits of a hybrid network by constructing a deployed wireless network using both technologies in accordance with many embodiments of the invention.
Embodiments in accordance with the invention describe an IEEE 802.11 deployment of multiple access points where each access point supports simultaneously some virtual access points (VAPs) that are part of single-channel architecture (SCA) as well as some VAPs that are part of multi-channel architecture (MCA). Current solutions require different systems and hardware for SCA and MCA, whereas embodiments of the proposed invention can run both MCA and SCA architectures simultaneously on the same devices.
In certain solutions, the customers deploying wireless networks would have to adjust their setup to the network rather than adjusting the network to the setup. Alternatively, these customers could double the equipment to support both architectures. In previous systems, the wireless AP is configurable for single channel use or for multi-channel use. Existing single access points cannot be used for both architectures at the same time. It is currently only possible to construct a hybrid MCA/SCA network only if both systems are deployed one-by-one in the same place using double the amount of APs. As such, when adjusting the setup to these networks, any change in station type or environment may require reconfiguring, reinstalling or replacing the network. This limits the client setup to supporting the current mode and does not leave room for future changes. Additionally, doubling the equipment is very expensive in costs, maintenance, energy use, and the like compared the method and system embodiments disclosed herein.
Implementing SCA architectures can be very complicated and falls out of the standards. So far, this has required some hardware and software adjustments that limit the available solutions to SCA only or MCA only. Constructing two kinds of wireless networks at the same time is not commonly required yet; most of the currently deployed wireless networks are constructed as multi-channel only. These multi-channel wireless networks have a roaming issue, which is known as a general problem of the Wi-Fi® system and for the SCA as well. However, there are various Wi-Fi® client devices such as sensors, robots, smartphones and laptops; their requirement for wireless networks is not always the same, so utilizing the benefits from both wireless network architectures can enhance the overall wireless network usefulness. Even if new protocols can solve the roaming issue in multi-channel networks in the future, many legacy Wi-Fi® systems will continue to be used and connectivity issues for those systems will remain.
In many embodiments of the disclosed system and method, single-channel and multi-channel hybrid wireless networks are constructed with reduced costs and hardware needs. In further embodiments, the hybrid access point devices and systems can separate the wireless network based on the purpose and benefit from both architectures. For example, performance demanding client devices such as laptops and personal computers (PCs) can use multi-channel architecture deployments which can easily have more channel and APs added if desired by the customer. IoT devices such as VoIP phones and systems for automation can utilize the benefits of single-channel architecture. In a number of embodiments of the present invention, an SCA BSSID can be considered as one cell and is also able to run 802.11k/r/v algorithms between the different SCA cells of the wireless deployment.
One advantage presented by the embodiments of the present invention is the cost savings to construct the hybrid wireless network. These saved costs can be utilized for the initial deployment and network management. In a number of embodiments, these initial cost savings may be achieved by reducing the number of APs which are required to deploy compared to the costs of constructing both MCA and SCA network systems separately. By way of example and not limitation, if a wireless deployment customer needs ten APs to cover all of an office area, it may be desired to construct a hybrid wireless network. This can be due to other solutions requiring twenty APs for each purpose (indicating a reduction of 50% of AP costs for a hybrid setup compared to a traditional SCA or MCA setup). Previous solutions would also require twenty sets of wires and construction costs for that wiring and installation. These increased wires and APs on the previous solutions lead to a requirement for more expensive switches that are configured to handle the increased number of AP wires, or to include a larger number of switches, and thus increased licenses for those switches.
With reference to
In such an MCA setup, an embodiment could be utilized that allows for multiple access points 100 to be placed in various areas in order to create an area of wireless signal coverage. Because each VAP 122, 124, 132, 134, 142, 144 has a unique BSSID but may have the same SSID between all APs, when a user with a client device that is connected to a first VAP 144 on one AP, walks out of range of the first VAP 144, but within range of a second VAP 134 on another AP, the client device must execute a process of disconnecting from the first VAP 144 and connecting to the second VAP 134 on a new access point to continue a connection to any other external networks connected to the access points 100 through the external Ethernet connection 110. A client device must initiate this disconnection/reconnection process each time the client device travels between VAP coverage areas. To avoid disconnecting, client devices will usually remain connected even when the signal is weak, which can cause a major impact to throughput.
Similar to the access point illustrated in
In an SCA setup, an embodiment could be utilized that allows for multiple access points 200 to be placed in various areas in order to create an area of wireless signal coverage. Because each VAP 222, 224, 232, 234, 242, 244 is identical between access points, when a user with a client device that is connected to a first VAP 244 on one AP, walks out of range of that AP, but within range of a second AP VAP, the client device does not have to execute a process of disconnecting from the first VAP 244 and connecting to the second VAP since the client device sees both VAP signals to be from the same BSSID source. A client device does not have to take any measures when traveling between multiple SCA VAP coverage areas.
With reference to
It can be appreciated by those skilled in the art that because the 802.11 VAPs 322, 332, 342 and the Channel Blanket VAPs 324, 334, 344 are tightly bonded to the 802.11 hardware 320, 330, 340, having both VAP types share a single physical device is a challenging task. In more embodiments, any changes to radio configuration done by one VAP type can affect the other type, especially when using a channel blanket setup which may require some major out-of-standard adjustment from the radio. In still more embodiments of the hybrid access point 300, any hardware access can take into account that a different VAP type may be using the same radio.
In such a hybrid setup, an embodiment could be utilized that allows for multiple access points to be placed in various areas in order to create an area of wireless signal coverage. Certain client devices may be configured to communicate through wireless networks by either SCA or MCA standards. Because each VAP 322, 324, 332, 334, 342, 344 can utilize either MCA or SCA, the large area covered by the hybrid access point 300 can include wireless network coverage for a wider array of client devices.
While a variety of hybrid access point systems and devices are described above with reference to
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While a variety of hybrid access point systems and devices are described above with reference to
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In such a hybrid setup, an embodiment could be utilized that allows for a wireless device to exchange data with a wired device. When a wireless device connects the hybrid AP, it may choose a single SCA or MCA VAP to connect to and can go through an association process. In a number of embodiments, the device will send at least one management frame to the VAP which can include the BSSID of the VAP. The frames can be received by the appropriate radio and use the BSSID in the frame to determine how to process it. In response to an uplink management frame, at least one management frame can be sent back to the device to complete the handshake. Once the association process is completed, the device information can be saved in the station database which can bind the device to the selected VAP.
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While a variety of hybrid access point structures and processes are described above with reference to
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While a variety of hybrid access point wireless channel allocations are described above with reference to
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While a variety of processes and methods for configuring and adding in hybrid access points are described above with reference to
System embodiments include computing devices such as a server computing device, a buyer computing device, and a seller computing device, each comprising a processor and addressable memory and in electronic communication with each other. The embodiments provide a server computing device that may be configured to: register one or more buyer computing devices and associate each buyer computing device with a buyer profile; register one or more seller computing devices and associate each seller computing device with a seller profile; determine search results of one or more registered buyer computing devices matching one or more buyer criteria via a seller search component. The service computing device may then transmit a message from the registered seller computing device to a registered buyer computing device from the determined search results and provide access to the registered buyer computing device of a property from the one or more properties of the registered seller via a remote access component based on the transmitted message and the associated buyer computing device; and track movement of the registered buyer computing device in the accessed property via a viewer tracking component. Accordingly, the system may facilitate the tracking of buyers by the system and sellers once they are on the property and aid in the seller's search for finding buyers for their property. The figures described below provide more details about the implementation of the devices and how they may interact with each other using the disclosed technology.
Information transferred via communications interface 1414 may be in the form of signals such as electronic, electromagnetic, optical, or other signals capable of being received by communications interface 1414, via a communication link 1416 that carries signals and may be implemented using wire or cable, fiber optics, a phone line, a cellular/mobile phone link, an radio frequency (RF) link, and/or other communication channels. Computer program instructions representing the block diagram and/or flowcharts herein may be loaded onto a computer, programmable data processing apparatus, or processing devices to cause a series of operations performed thereon to produce a computer implemented process.
Embodiments have been described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems) and computer program products according to embodiments. Each block of such illustrations/diagrams, or combinations thereof, can be implemented by computer program instructions. The computer program instructions when provided to a processor produce a machine, such that the instructions, which execute via the processor, create means for implementing the functions/operations specified in the flowchart and/or block diagram. Each block in the flowchart/block diagrams may represent a hardware and/or software module or logic, implementing embodiments. In alternative implementations, the functions noted in the blocks may occur out of the order noted in the figures, concurrently, etc.
Computer programs (i.e., computer control logic) are stored in main memory and/or secondary memory. Computer programs may also be received via a communications interface 1412. Such computer programs, when executed, enable the computer system to perform the features of the embodiments as discussed herein. In particular, the computer programs, when executed, enable the processor and/or multi-core processor to perform the features of the computer system. Such computer programs represent controllers of the computer system.
The server 1530 may be coupled via the bus 1502 to a display 1512 for displaying information to a computer user. An input device 1514, including alphanumeric and other keys, is coupled to the bus 1502 for communicating information and command selections to the processor 1504. Another type or user input device comprises cursor control 1516, such as a mouse, a trackball, or cursor direction keys for communicating direction information and command selections to the processor 1504 and for controlling cursor movement on the display 1512.
According to one embodiment, the functions are performed by the processor 1504 executing one or more sequences of one or more instructions contained in the main memory 1506. Such instructions may be read into the main memory 1506 from another computer-readable medium, such as the storage device 1510. Execution of the sequences of instructions contained in the main memory 1506 causes the processor 1504 to perform the process steps described herein. One or more processors in a multi-processing arrangement may also be employed to execute the sequences of instructions contained in the main memory 1506. In alternative embodiments, hard-wired circuitry may be used in place of or in combination with software instructions to implement the embodiments. Thus, embodiments are not limited to any specific combination of hardware circuitry and software.
The terms “computer program medium,” “computer usable medium,” “computer readable medium”, and “computer program product,” are used to generally refer to media such as main memory, secondary memory, removable storage drive, a hard disk installed in hard disk drive, and signals. These computer program products are means for providing software to the computer system. The computer readable medium allows the computer system to read data, instructions, messages or message packets, and other computer readable information from the computer readable medium. The computer readable medium, for example, may include non-volatile memory, such as a floppy disk, ROM, flash memory, disk drive memory, a CD-ROM, and other permanent storage. It is useful, for example, for transporting information, such as data and computer instructions, between computer systems. Furthermore, the computer readable medium may comprise computer readable information in a transitory state medium such as a network link and/or a network interface, including a wired network or a wireless network that allow a computer to read such computer readable information. Computer programs (also called computer control logic) are stored in main memory and/or secondary memory. Computer programs may also be received via a communications interface. Such computer programs, when executed, enable the computer system to perform the features of the embodiments as discussed herein. In particular, the computer programs, when executed, enable the processor multi-core processor to perform the features of the computer system. Accordingly, such computer programs represent controllers of the computer system.
Generally, the term “computer-readable medium” as used herein refers to any medium that participated in providing instructions to the processor 1504 for execution. Such a medium may take many forms, including but not limited to, non-volatile media, volatile media, and transmission media. Non-volatile media includes, for example, optical or magnetic disks, such as the storage device 1510. Volatile media includes dynamic memory, such as the main memory 1506. Transmission media includes coaxial cables, copper wire and fiber optics, including the wires that comprise the bus 1502. Transmission media can also take the form of acoustic or light waves, such as those generated during radio wave and infrared data communications.
Common forms of computer-readable media include, for example, a floppy disk, a flexible disk, hard disk, magnetic tape, or any other magnetic medium, a CD-ROM, any other optical medium, punch cards, paper tape, any other physical medium with patterns of holes, a RAM, a PROM, an EPROM, a FLASH-EPROM, any other memory chip or cartridge, a carrier wave as described hereinafter, or any other medium from which a computer can read.
Various forms of computer readable media may be involved in carrying one or more sequences of one or more instructions to the processor 1504 for execution. For example, the instructions may initially be carried on a magnetic disk of a remote computer. The remote computer can load the instructions into its dynamic memory and send the instructions over a telephone line using a modem. A modem local to the server 1530 can receive the data on the telephone line and use an infrared transmitter to convert the data to an infrared signal. An infrared detector coupled to the bus 1502 can receive the data carried in the infrared signal and place the data on the bus 1502. The bus 1502 carries the data to the main memory 1506, from which the processor 1504 retrieves and executes the instructions. The instructions received from the main memory 1506 may optionally be stored on the storage device 1510 either before or after execution by the processor 1504.
The server 1530 also includes a communication interface 1518 coupled to the bus 1502. The communication interface 1518 provides a two-way data communication coupling to a network link 1520 that is connected to the world wide packet data communication network now commonly referred to as the Internet 1528. The Internet 1528 uses electrical, electromagnetic or optical signals that carry digital data streams. The signals through the various networks and the signals on the network link 1520 and through the communication interface 1518, which carry the digital data to and from the server 1530, are exemplary forms or carrier waves transporting the information.
In another embodiment of the server 1530, interface 1518 is connected to a network 1522 via a communication link 1520. For example, the communication interface 1518 may be an integrated services digital network (ISDN) card or a modem to provide a data communication connection to a corresponding type of telephone line, which can comprise part of the network link 1520. As another example, the communication interface 1518 may be a local area network (LAN) card to provide a data communication connection to a compatible LAN. Wireless links may also be implemented. In any such implementation, the communication interface 1518 sends and receives electrical electromagnetic or optical signals that carry digital data streams representing various types of information.
The network link 1520 typically provides data communication through one or more networks to other data devices. For example, the network link 1520 may provide a connection through the local network 1522 to a host computer 1524 or to data equipment operated by an Internet Service Provider (ISP). The ISP in turn provides data communication services through the Internet 1528. The local network 1522 and the Internet 1528 both use electrical, electromagnetic or optical signals that carry digital data streams. The signals through the various networks and the signals on the network link 1520 and through the communication interface 1518, which carry the digital data to and from the server 1530, are exemplary forms or carrier waves transporting the information.
The server 1530 can send/receive messages and data, including e-mail, program code, through the network, the network link 1520 and the communication interface 1518. Further, the communication interface 1518 can comprise a USB/Tuner and the network link 1520 may be an antenna or cable for connecting the server 1530 to a cable provider, satellite provider or other terrestrial transmission system for receiving messages, data and program code from another source.
The example versions of the embodiments described herein may be implemented as logical operations in a distributed processing system such as the system 1500 including the servers 1530. The logical operations of the embodiments may be implemented as a sequence of steps executing in the server 1530, and as interconnected machine modules within the system 1500. The implementation is a matter of choice and can depend on performance of the system 1500 implementing the embodiments. As such, the logical operations constituting said example versions of the embodiments are referred to for e.g., as operations, steps or modules.
Similar to a server 1530 described above, a client device 1501 can include a processor, memory, storage device, display, input device and communication interface (e.g., e-mail interface) for connecting the client device to the Internet 1528, the ISP, or LAN 1522, for communication with the servers 1530.
The system 1500 can further include computers (e.g., personal computers, computing nodes) 1505 operating in the same manner as client devices 1501, where a user can utilize one or more computers 1505 to manage data in the server 1530.
Referring now to
The above description presents the best mode contemplated for carrying out the present embodiments, and of the manner and process of practicing them, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which they pertain to practice these embodiments. The present embodiments are, however, susceptible to modifications and alternate constructions from those discussed above that are fully equivalent. Consequently, the present invention is not limited to the particular embodiments disclosed. On the contrary, the present invention covers all modifications and alternate constructions coming within the spirit and scope of the present disclosure. For example, the steps in the processes described herein need not be performed in the same order as they have been presented, and may be performed in any order(s). Further, steps that have been presented as being performed separately may in alternative embodiments be performed concurrently. Likewise, steps that have been presented as being performed concurrently may in alternative embodiments be performed separately.
This application claims priority to and the benefit of U.S. Provisional Patent Application No. 62/663,124, filed Apr. 26, 2018, the contents of which are hereby incorporated by reference herein for all purposes.
| Number | Date | Country | |
|---|---|---|---|
| 62663124 | Apr 2018 | US |
