US 7,599,286 B2Granted

System and method for achieving path symmetry in an internet protocol (IP) based network

AssigneeTelefonaktiebolaget L M Ericsson (publ)

InventorsSuresh Bhogavilli, Samir Shah, Kaarthik Sivakumar

Life of this patent

Estimating the term…

Loading patent…

Abstract

A system and method for improving network performance when communicating between a first site network and a second site network via an IP-based transport network. The site networks include a LAN, a plurality of host/media gateways (MGWs) connected to the LAN, and pairs of first and second Site Edge Routers (SERs) connected to the LAN for handling traffic from different host/MGWs. The SERs are configured as redundant backup pairs in which each SER in a given pair backs up the other SER in the pair. Each SER is connected to a different Provider Edge (PE) router in the transport network via a dedicated link that has sufficient spare capacity to carry traffic coming from both of the SERs in a given pair of SERs in case one of the SERs fails. The SERs provide preferred routing prefixes to the PE routers, thereby guaranteeing symmetric paths for bidirectional traffic.

Claims23

Dependent claims

A system for improving network performance when communicating between a first site network and a second site network via an Internet Protocol (IP) based transport network, wherein the first and second site networks include a local area network (LAN) and a plurality of host/media gateways (MGWs) connected to the LAN, said system comprising:

first and second Site Edge Routers (SERs) in each site network that handle traffic from different host/MGWs, said SERs being connected to the LAN, and wherein each SER carries a first portion of the traffic from the SER's site network with a first preference, and a second portion of the traffic from the SER's site network with a second, lower preference;
first and second Provider Edge (PE) routers in the transport network, wherein the first SER connects to the first PE router via a first SER-PE link, and the second SER connects to the second PE router via a second SER-PE link, each of said SER-PE links carrying bidirectional traffic for both the first and second SERs, and each of said SER-PE links having enough spare capacity to carry all of the traffic coming from both the first and second SERs in case the first or second SER fails;
and
means within the first and second SERs for guaranteeing symmetric paths for bidirectional traffic on each SER-PE link by providing preferred routing information to the first and second PE routers.

1 more element

A method of providing path symmetry, resilience, and scalability when communicating between a first site network and a second site network via an Internet Protocol (IP) based transport network, wherein the first and second site networks include a local area network (LAN) and a plurality of host/media gateways (MGWs) connected to the LAN, said method comprising:

connecting first and second Site Edge Routers (SERs) to the LAN in each site network to handle traffic from different hostlMGWs, wherein each SER carries a first portion of the traffic from the SER's site network with a first preference, and a second portion of the traffic from the SER's site network with a second, lower preference;
connecting the first and second SERs to first and second Provider Edge (PE) routers in the transport network, wherein the first SER is connected to the first PE router via a first SER-PE link, and the second SER is connected to the second PE router via a second SER-PE link, each of said SER-PE links carrying bidirectional traffic for both the first and second SERs, and each of said SER-PE links having enough spare capacity to carry all of the traffic coming from both the first and second SERs in case the first or second SER fails;
and
guaranteeing symmetric paths for bidirectional traffic on each SER-PE link by providing by the first and second SERs, preferred routing information to the first and second PE routers.

1 more element

Dependencies are inferred from the claim text.