Cisco Technology, Inc.

Suresh Sangiah

R Ashby Armistead

Stephen Ma

Jagannadh Tangirala

Amit Chandra

Elangovan Kembanur Natarajan

In one embodiment, a stack manager of an operating system on a network device configures an egress abstract stack port and an ingress abstract stack port, where the configuring maps one or more physical ports of the network device to a corresponding abstract stack port. The stack manager then transmits platform-independent egress stack discovery messages on the egress abstract port to a remote ingress abstract stack port of an adjacent stack member, and receives platform-independent ingress stack discovery messages on the ingress abstract port from a remote egress abstract stack port of an adjacent stack member. The stack manager may then provide platform-independent stacked network device operation using connectivity between the egress abstract stack port and remote ingress abstract stack port, and connectivity between the remote egress abstract stack port and ingress abstract stack port.

Abstract stack ports to enable platform-independent stacking

An access server architecture, and methods for use of the architecture to increase the scalability of and balance processor load for a network access server device, are disclosed. In this architecture, packet forwarding and packet processing are distributed amongst cards serving low-speed access lines (i.e., line cards). Thus, as the number of line cards expands, forwarding resources are expanded in at least rough proportion. The NAS route switch controller and the high-speed ports used to access the network are largely relieved of packet processing tasks for traffic passing through the server. The egress port uses a distribution engine that performs the routing lookup for packets received at the high-speed interface, tags the packets with an adjacency table pointer, and sends them to the appropriate forwarding engine for packet processing. The route switch controller, largely uninvolved in the processing of packets, updates routing information needed by each distribution or forwarding engine.

Intraserver tag-switched distributed packet processing for network access servers

An access server architecture, and methods for use of the architecture, are disclosed. The architecture and methods are designed to increase the scalability of and balance processor load for a network access server device. In this architecture, packet forwarding and packet processing are distributed amongst the cards serving the low-speed access lines, such that each line card is responsible for performing forwarding and packet processing for packets associated with the low-speed ports that line card serves. As the number of line cards expands, forwarding resources are expanded in at least rough proportion. The NAS route switch controller, and the high-speed ports, are largely relieved of packet processing tasks because the egress port uses a distribution engine that performs a cursory examination on one or more header fields on packets received&#x2014;comprehending only enough information to allow each packet to be distributed to the appropriate line card for full packet processing.

Distributed packet processing architecture for network access servers

An access server architecture, and methods for use of the architecture, are disclosed. The architecture and methods are designed to increase the scalability of and balance processor load for a network access server. In this architecture, packet forwarding and packet processing are distributed amongst the cards serving the low-speed access lines, such that each line card is responsible for performing forwarding and packet processing for packets associated with the low-speed ports that line card serves. As the number of line cards expands, forwarding resources are expanded in at least rough proportion. The NAS route switch controller, and the high-speed ports, are largely relieved of packet processing tasks because the egress port uses a distribution engine that performs a cursory examination on one or more header fields on packets received&#x2014;comprehending only enough information to allow each packet to be distributed to the appropriate line card for full processing.

Growing community of inventors

Fremont, CA, United States of America

Suresh Sangiah