WO2012074353A1

WO2012074353A1 - A method of distributing data traffic

Info

Publication number: WO2012074353A1
Application number: PCT/MY2011/000085
Authority: WO
Inventors: Sahar Abdul Aziz Mageeo.Al-Taub; Kiong Chan.Seng; Mazlan Abbas; Ting Kee Ngoh
Original assignee: Mimos Bhd
Current assignee: Mimos Bhd
Priority date: 2010-11-29
Filing date: 2011-06-08
Publication date: 2012-06-07
Anticipated expiration: 2013-05-29
Also published as: MY175206A

Abstract

A method of distributing data traffic to predetermined destinations in wireless multi hop networks is provided, the method includes the steps of receiving data traffic from a source, breaking out received traffic and redistributing traffic to predetermined destinations which are configurable as recorded in a mapping table.

Description

A METHOD FOR DISTRIBUTING DATA TRAFFIC

FIELD OF INVENTION The present invention relates to a method of distributing data traffic to predetermined destinations in wireless multi hop networks.

BACKGROUND OF INVENTION Popular designs of wireless networks today are Point-to-Point, Point-to-Muhipoint and mesh topologies. In point-to-multipoint (PMP) designs, end nodes can exchange control signals but data or bearer packets cannot traverse from one node to another. The challenge here is making end nodes exchange data packets and control messages without modifying standards. US 20090073995 Al describes an apparatus configures to receive traffic of different types such as internet service domain traffic and operators service domain traffic. However, in this solution, the apparatus requires permission from an authentication module to allow a local breakout Further, breakout rules in this case are only applicable to home agent and not beyond that

However, as most of the prior art is focussed on internet service domain traffic and mobility, a more comprehensive solution that allows for mapping of data is needed in wireless networks. SUMMARY OF INVENTION

Accordingly, there is provided a method of distributing data traffic to predetermined destinations in wireless multi hop networks, the method includes the steps of receiving data traffic from a source, breaking out received traffic and redistributing traffic to predetermined destinations which are configurable as recorded in a mapping table.

Further, there is provided a method of distributing data traffic to predetermined destinations in wireless multi hop networks, the method includes the steps of receiving data traffic from a source, instantiating and managing data bearer between a data path function, selecting a payload traversing the data bearer, scanning a chain of headers from data traffic, identifying a plurality of fields to be amended, calling up a mapping t ble, determining encapsulation of traffic, changing source and destination addresses of the header when there is no encapsulation of traffic and sending data traffic to the predetermined destination.

The present invention consists of several novel features and a combination of parts hereinafter fully described and illustrated in the accompanying description and drawings, it being understood that various changes in the details may be made without departing from the scope of the invention or sacrificing any of the advantages of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be fully understood from the detailed description given herein below and the accompanying drawings which are given by ay of illustration only, and thus are not limitative of the present invention, wherein:

Figure 1 shows an example of a method of distributing data traffic to predetermined destinations in wireless multi hop networks wherein two base stations forward or route data traffic in Worldwide Interoperability tor Microwave Access (WiMAX) in the preferred embodiment of the invention; Figure 2 shows a method of distributing data traffic to predetermined destinations in wireless multi hop networks in a location of distributed date path function and a mapping table in the preferred embodiment of the invention;

Figure 3 shows a flowchart of steps performed by the distributed data path function ( UPF);

Figure 4 shows an example of a chain of headers followed by the user payload in an embodiment of the invention;

Figure 5 shows a chart depicting IP and encapsulation details of fields in both types of headers;

Figure 6 shows an example of a topology with data traffic distribution as recorded in the mapping table; Figure 7 shows a flow of messages flowing to and from the distributed data path function using WiMAX; and Figure 8 shows the contributing functions of the distributed data path function and the mapping table.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The present invention relates to a method of distributing data traffic to predetermined destinations in wireless multi hop networks. More particularly, the method is a method of incorporating multiple performance metrics into a shortest routing protocol in wireless mesh networks. Hereinafter, this specification will describe the present invention according to the preferred embodiment of the present invention. However, it is to be understood that limiting the description to the preferred embodiment of the invention is merely to facilitate discussion of the present invention and it is envisioned that those skilled in the art may devise various modifications and equivalents without departing from the scope of the appended claims.

The following detailed description of the preferred embodiment will now be described in accordance with the attached drawings, either individually or in combination.

Figure 2 illustrates a method of distributing data traffic to predetermined destinations in wireless multi hop networks. The method includes the steps of receiving data traffic from a source, breaking out received traffic and redistributing traffic to predetermined destinations which are configurable as recorded in a mapping table. For example, a distributed data path function (DDPF) refers to a mapping table in order to guide or breakout traffic. The mapping table describes a configuration of a network where the source, destination and data path identifications are recorded in the mapping table. The mapping table allows for single or multi-hdp configurations. The mapping table can be configured for fixed topology or the mapping table may be adapted b an operator as part of Operation and Maintenance. Figure 1 shows an example of this embodiment wherein two base stations cannot forward or route data traffic in Worldwide Interoperability for Microwave Access (WiMAX). A data path function at the source, such as in Access Service Network Gateway (ASN GW) in WiMAX, forwards or routes data traffic to the distributed data path function (DDPF) in the method. The DDPF performs breakout of traffic and redistributes the traffic to destinations as configured in the mapping table. Hie destinations can be configured in single hop, multi hop, random, mesh or any topology as seen fit for application by one skilled in the art.

A preferred embodiment of the method of distributing data traffic to predetermined destinations in wireless multi hop networks is described herein. The method includes the steps of receiving data traffic from a source, instantiating and managing data bearer between a data path function, selecting a payload traversing the data bearer, scanning a chain of headers from data traffic, identifying a plurality of fields to be amended, calling up a mapping table, determining encapsulation of traffic, changing source and destination addresses of the header when there is no encapsulation of traffic and sending data traffic to the predetermined destination as seen in Figure 3. When there is encapsulation, data path identification field is changed.

The DDPF may be located in a router, device, module or chip of a gateway or a router or another device. The DDPF receives traffic from the source wherein the traffic includes user payload with a chain of headers preceding the user payload. Examples of the headers include transport Internet Protocol (IP) header, encapsulation header and other headers that may be used in the traffic. Figure 4 shows an example of a chain of headers followed by the user payload. The DDPF scans the headers to identify their types and amendable fields in each type. If the traffic is simple IP traffic, this means that the IP header exists with relevant fields. If the traffic is tunneled traffic, then the encapsulation header is found following IP header. Details of fields in both types of headers are depicted in Figure 5. It is to be understood that headers of other types may also be used depending on application of the method.

In order to breakout traffic to an intended destination within a configure topology, the DDPF changes two fields in the IP header (501 and 502 in Figure 5) if the traffic is not capsulated. For encapsulated traffic, three fields (501, 502 and 503 in Figure 5) are changed by DDPF. Source address (501 in Figure 5) of the IP header refers to the source IP address of the traffic. Destination IP addresses (502 in Figure 5) of the IP header refers to a destmation of the traffic. A traffic path for the traffic to follow is represented by data path identification (503 in Figure 5). In order for the DDPF to get correct values of the fields to amend, a mapping table (MMT) is created. The MMT explains topology configuration and can handle single or multihop scenarios as well as be part of Operation and Maintenance. The MMT may include setup of any tunnels and additional functionality that may be required. As described earlier, the mapping table guides traffic to destinations siich as mesh topology.

Figure 6 shows a topology, where source data traffic is distributed amongst network elements configured in any fashion. Topology map for this example is illustrated in Table 1.

Table 1 : Example of mapping table for a topology

Referring to Figure 6 and Table 1, for example DDPFl receives source traffic (either tunneled or not), which follows the steps of the method as seen in Figure 3 for mapping or disseminating traffic to two paths. As seen in Figure 6, path 1 is mapped towards network element 1 followed by end users 1, 2 and 3 as well as path 2 towards DDPF2. Similarly, DDPF2 maps or disseminates traffic to path 3 and path 4 then to network elements and DDPF towards end users. Traffic mapping or distribution is done by referring to the MMT which is broadcast to all neighboring nodes. The MMT should be updated in case of mobility, handover, configuration change, classification rule change or any other reason that causes topology change that allows for single hop or multi hop topology. Values of the source, destination and key, tag or connection identification values in Table 1 are obtained by the DDPF from the IP headers and encapsulation headers after de-capsulation. The values are recorded in the MMT for further reference in routing. A set of messages are present for each wireless standard to set up, modify or remove the data path. A flow of messages fof standards such as WiMAX are changed to cater to required processes of DDPF. This flow of messages is shown in Figure 7.

The data path function (DPF) is used to set up a bearer plane between base stations or between other entities such as gateways or between gateways and base stations. Each date path function is responsible for instantiating and managing data bearer between the data path function and another data path function as well as selecting the user payload traversing an established data bearer. User Datagram Protocol Internet Protocol (UDP/IP) is an example of a transport protocol for communication between peer DPFs. Other types of traffic may be used as well. A peer DPF at each end is addressed by the ID of network component which hosts the data path such as base station ID (BSID). Many technologies are used for tunneling or setting up path such as Generic Route Encapsulation (GRE), Multiprotocol Label Switching (MPLS) and 802.1Q Virtual LANS (VLANs). Granularity of tunnels are defined and handled by the DPF.

Figure 8 illustrates a contributed function DDPF and the mapping table. The traffic breakout step further includes the steps of building a DDPF to negotiate with DPF at different peer or network element of classification rules, building a MMT to save a source and destination addresses captured from TP headers or forwarded traffic, saving the data path identifications of different service flow captured from encapsulation headers for tunneled traffic after de- capsulating traffic, identifying the source and destination addresses for the TP header and deciding on a correct route accordingly, identifying a key, tag values or data path identification for the service flow to be routed and the MMT may be broadcasted to all neighboring devices wherein each neighboring device selects relevant trafific.

A router includes at least one switch configured to switch incoming traffic to at least one traffic paths, a data path function and a network address translation function or network address port translation function. T e switch is selected from at least one of a layer 3 switch and a public or private switch. The switch is provided between the data path function or a gateway output, and other traffic tunnel end point This invention is adapted for use with single hop and multi hop wireless networks of various topologies. The disclosed invention is suitable, but not restricted to, for use in performance forwarding data traffic to destinations in any wireless networks such as WiMAX.

Claims

1. A method of distributing data traffic to predetermined destinations in wireless multi hop networks, the method includes the steps of: i. receiving date traffic from a source;

ii. breaking out received traffic; and

in. redistributing traffic to predetermined destinations which are configurable as recorded in a mapping table.

2. The method as claimed in claim 1, wherein a distributed data path function (DDPF) refers to the mapping table in order to guide or breakout traffic.

3. The method as claimed in claim 1, wherein the mapping table allows for single configurations.

4. The method as claimed in claim 1, wherein the mapping table allows for multi-hop configurations.

5. The method as claimed in claim 1, wherein the mapping table is configured for fixed topology.

6. The method as claimed in claim 1, wherein the mapping table is adapted by an operator as part of Operation and Maintenance.

A method of distributing data traffic to predetermined destinations in wireless multi hop networks, the method includes the steps of:

i. receiving data traffic from a source;

ii. instantiating and managing data bearer between data path functions;

iii. selecting a payload traversing the data bearer;

iv. scanning a chain of headers from data traffic;

v. identifying a plurality of fields to be amended;

vi. calling up a mapping table;

vii. determining encapsulation of traffic;

viii. changing source and destination addresses of the header when there is no encapsulation of traffic; and

ix. sending data traffic to the predetermined destination.

The method as claimed in claim 7, wherein if traffic is encapsulated, data path identification of header is changed before sending data traffic to the predetermined destination.

The method as claimed in claim 7, wherein a distributed data path function (DDPF) is located in a router, device, module or chip of a gateway or a router or another device.

10. The method as claimed in claim 9, wherein the DDPF receives traffic from the source wherein the traffic includes user payload with a chain of headers preceding the user payload.

11. The method as claimed in claim 9, wherein the DDPF scans the headers to identify their types and amendable fields in each type.

12. The method as claimed in claim 7, wherein the mapping table (MMT) is updated in case of mobility, handover, configuration change, classification rule change or any other reason that causes topology change that allows for single hop or multi hop topology.

13. The method as claimed in claim 7, wherein the data path function (DPF) is used to set up a bearer plane between base stations or between other entities.

14. The method as claimed in claim 7, wherein the method further includes the steps of:

i. building a DDPF to negotiate with DPF at different peer or network element of classification rules; ii. building a MMT to save a source and destination addresses captured from TP headers or forwarded traffic; iii. saving the data path identifications of different service flow captured from encapsulation headers for tunneled traffic after de-capsulating traffic; iv. identifying the source and destination addresses for the LP header and deciding on a correct route accordingly; v. identifying a key, tag values or data path identification for the service flow to be routed; and vi. broadcasting the MMT to all neighboring devices wherein each neighboring device selects relevant traffic.