Patent Application
20080037572
The invention relates generally to communications networks. More specifically, the invention provides for coordination of logical channels in a communication network.
End-to-end Quality of Service (QoS) describes the ability of a network to provide service as required by a particular type of network traffic. The service is provided from one end of the network to another. Differentiated Services (DiffServ) describes one type of service model in end-to-end QoS provisioning in which differing QoS requirements may be met. The network thus delivers a service of the type based on the QoS specified by each packet.
In Long Term Evolution (LTE), QoS provisioning for IP traffic uses tools standardized by the Internet Engineering Task Force (IETF). A logical channel carries information or data that may be in the same physical channel but may be separated logically from other data. In a radio access network (RAN), appropriate logical channels are selected for transmission of each packet, each logical channel providing a given QoS configuration.
Different service classes of traffic may have different QoS requirements such that classes of traffic are categorized in a respective class of service (CoS). Also, a data packet being transmitted in a logical channel with a corresponding QoS configuration may be subject to specified transmission methods or forwarding treatment such as a Differentiated Services Code Point (DSCP). For example, per-hop behavior (PHB) may vary based on the CoS and/or QoS configurations or a DSCP range at each network node in a corresponding logical channel.
There exists a need in the art for a method and system for efficiently transmitting data in a communication network in a logical channel in which the transmitted data corresponds to the logical channel or a corresponding DSCP.
The following presents a simplified summary in order to provide a basic understanding of some aspects of the invention. The summary is not an extensive overview of the invention. It is neither intended to identify key or critical elements of the invention nor to delineate the scope of the invention.
The following summary merely presents some concepts of the invention in a simplified form as a prelude to the more detailed description below.
In one example, a method is provided for selecting or determining a logical channel for data transmission, the logical channel corresponding to a Quality of Service (QoS) configuration. In another example, the logical channel may be selected based on the data packet. For example, the data packet may be marked with a Differentiated Services Code Point (DSCP) for selecting the logical channel.
In another example, a transmitter is provided for determining a logical channel or a default logical channel corresponding to a QoS. The QoS may further be indicated by the data packet which may be marked. For example, the data packet may include a bit pattern such as a DSCP for indicating a logical channel and/or a corresponding QoS for data transmission.
In another example, a receiver is provided for receiving a data transmission corresponding to a logical channel. The receiver may identify the logical channel and apply a corresponding QoS based on the identified logical channel.
In another example, a computer-readable medium is provided containing computer-executable code for identifying or selecting a logical channel for data transmission based on a data packet. For example, the logical channel may be selected based on a DSCP in a header of the data packet.
A more complete understanding of the present invention and the advantages thereof may be acquired by referring to the following description in consideration of the accompanying drawings, in which like reference numbers indicate like features, and wherein:
In the following description of the various embodiments, reference is made to the accompanying drawings, which form a part hereof, and in which is shown by way of illustration various embodiments in which the invention may be practiced. It is to be understood that other embodiments may be utilized and structural and functional modifications may be made without departing from the scope and spirit of the present invention.
Differentiated Services (DiffServ) may provide for simple or coarse methods for categorizing traffic into different classes (CoS) or to apply corresponding QoS parameters to each of the classes. For example, in a packet forwarding path, DiffServ may map a code point contained in a field in the packet header to a particular forwarding treatment (i.e., PHB) at each network node along the path of transmission. In this example, a small bit pattern such as the Differentiated Services Code Point (DSCP) in each data packet may be used to mark the data packet to receive a particular PHB at a network node. Marking may be accomplished, for example, in a DiffServ field in a data packet.
In the example illustrated in
In another example, the DSCP marks a packet in the IPv4 Type of Service (ToS) octet or the IPv6 Traffic Class octet to receive a particular forwarding treatment (i.e., PHB). As
In one example, data traffic may be further classified based on delay, reliability, or throughput. As
Additional bits may be provided for additional desired parameters (e.g., bits 6-7 in
In one example of the present invention, a logical channel may be preconfigured for a given DSCP value or set of DSCP values. The logical channel may also provide a given QoS such that the DSCP may be associated with a corresponding QoS configuration. In another example, default QoS configurations may be used for most kinds of data traffic such that setup signaling is not necessary. A default QoS configuration may be associated with a preconfigured logical channel that may be available without prior QoS negotiation or setup signaling.
In another example, a mapping is provided for the DSCP or set or range of DSCP values and a corresponding QoS configuration with an associated logical channel. For example, a DSCP range may be provided with a corresponding default QoS configuration. The default QoS configuration may be associated with a default logical channel that may provide the default QoS configuration.
The transmitter 300 may further include a compressor 304 for compressing the IP header. In this example, the received DSCP may be identified by the DSCP identifier 302 prior to compression of the IP header. Thus, the DSCP may be copied from the original IP packet followed by compression of the IP header by the compressor. The logical channel selector 305 in this example may select the logical channel according to the received DSCP field. Alternatively, the logical channel may also be selected in a different network node based on the DSCP.
In another example, the IP data packet received at the transmitter 300 may not contain an available DSCP. The IP data packet may be received at the input 302 of the transmitter 300, however, the DSCP identifier 302 in this example does not identify a DSCP as being available. In this example, the logical channel selector 305 may select an appropriate logical channel based on alternate network layers. For example, the logical channel selector 305 may select a default preconfigured logical channel based on network layers that are higher than the IP layer. Such network layers may include, for example, UDP, TCP, RTP, FTP, HTTP, etc. Also, logical channels may be configured to support combinations of network layers, for example, a logical channel may be configured to support all UDP and RTP traffic.
As illustrated in the example of
Also, in another example, compression of the header in the IP packet occurs in same network node as the MAC layer node (the “YES” branch of STEP 602). In this example, DSCP information need not be carried between nodes in the network. Therefore, in this example, the logical channel may be selected according to the DSCP (STEP 605).
In another example, an IP protocol is used within the radio access network (RAN) (the “YES” branch of STEP 603). As illustrated in the example of
In another example, a DSCP is available (“YES” branch of STEP 502) and the packet is not compressed (“NO” branch of STEP 601). A logical channel may be selected that may correspond to the value of the DSCP. In one example illustrated in
In another example, the DSCP is not within a default range (the “NO” branch of STEP 801). In this example, a logical channel is selected for an unknown DSCP (STEP 803). The selected logical channel in this example may be preconfigured for an unknown DSCP such that one default logical channel may be used when the DSCP does not belong to a known range or a default range. In another example, one default logical channel may be used for any DSCP of an IP packet that does not belong to a known default range. In yet another example, a set of default logical channels may be provided for use with transmission of an IP packet containing a DSCP that does not belong to a default range.
The present invention includes any novel feature or combination of features disclosed herein either explicitly or any generalization thereof. While the invention has been described with respect to specific examples including presently preferred modes of carrying out the invention, those skilled in the art will appreciate that there are numerous variations and permutations of the above described systems and techniques. Thus, the spirit and scope of the invention should be construed broadly as set forth in the appended embodiments.
This application claims the benefit of U.S. Provisional Application No. 60/755,094, filed on Jan. 3, 2006, and which is incorporated herein by reference.
| Number | Date | Country | |
|---|---|---|---|
| 60755094 | Jan 2006 | US |
