Cisco Technology, Inc.

Dheerendra Talur

Pradosh Mohapatra

Clarence Filsfils

Rex Emmanuel Fernando

Karthik Narayanan Subramanian

David Delano Ward

John H W Bettink

Derek Man-Kit Yeung

Kannan Varadhan

Pranav Dharwadkar

Avneesh Sachdev

Paul Arthur Jensen

Xiongbin Ma

Bharath Vasudevan

In one embodiment, a service domain router (SDR) establishes a virtual fabric interface between the SDR and at least one peer SDR in a computer network. When the SDR receives a routing advertisement from the peer SDR, where the routing advertisement provides nexthop (NH) information for one or more network routes, the SDR may add the one or more network routes to a routing information base (RIB) listing the peer SDR as a next-to-nexthop (NNH) for the network routes. A forwarding information base (FIB) on the network device then resolves the NNH for the corresponding network routes to an egress interface of the peer SDR, such that packets received at the SDR and destined along a particular route of the one or more network routes may be forwarded via the egress interface of the peer SDR.

Collapsed forwarding for service domain routers

In one embodiment, a packet switching device assigns a same particular packet switching label to each particular route of a plurality of particular routes having the same one or more best paths, wherein the plurality of particular routes includes routes from at least two different forwarding groups. A forwarding group is defined as a specific route, one or more routes associated with a same customer edge router, or one or more routes associated with a single virtual routing and forwarding domain (VRF). The packet switching device advertises to other packet switching device(s) to add this same particular label to packets having one of the plurality of particular routes, which they do. The packet switching device then packet switches packets based on the particular label received in a label field in a header of these packets.

Packet switching label assignment across multiple packet switching forwarding groups

A router is described that includes a routing table containing route information and a module to evaluate a route and detect a loop path associated with the route using the routing table. A process is described to detect and eliminate routing loops associated with recursive routes in a routing table, so as to provide a routing table that will be loop free.

Methods and apparatus for providing loop free routing tables

Disclosed are, inter alia, methods, apparatus, computer-storage media, mechanisms, and means associated with subsets of the Forward Information Base (FIB) distributed among line cards in a switching device; especially wherein one or more of the line cards does not contain the complete FIB, and this line card forwards packets, for which it does not have the forwarding information, to another line card which has the forwarding information for the packet.

Subsets of the forward information base (FIB) distributed among line cards in a switching device

A method of selecting routing tables to include in a network line card consists of determining dependencies of local routes on remote routes using a reference count on prefixes, and selectively downloading remote routes when resolution of a route has a dependency on a remote route. In one embodiment, only remote routes that are needed to forward traffic are downloaded to a network line card.

Route dependency selective route download

Growing community of inventors

San Ramon, CA, United States of America

Dheerendra Talur