Cabletron Systems, Inc.

Enterasys Networks, Inc.

Enterasys, Inc.

Kevin Yohe

Kurt A Dobbins

Brendan J Fee

Michael Skubisz

Chris Oliver

David L Cullerot

Theodore C Len

Thomas A Grant

Philip Andlauer

David H Bahi

Laura Kane

David Ruffen

William T Haggerty

Rich Soczewinski

Paul Simoneau

Len Cormier

Kris Dobbins

David J Ruffen

Connection-oriented services for packet switched data communications networks are provided, including distributed MAC and protocol alias addresses discovery. Link state topology exchanges provide each switch with network topology graphs to determine paths from source to destination end systems. Broadcast frames are resolved to unicast frames to reduce broadcast traffic. Policy restrictions may be applied prior to connection setup. Connection management includes source-routed mapping of connections on the desired path. Distributed call rerouting is provided so switches receive topology change notifications and unmap failed link connections. Broadcast/unknown services provide non-resolvable packet restricted flooding. Connection-oriented switching is provided based on source and destination MAC addresses. Resolution of networks outside the switch domain is enabled by listening for network and server route advertisements and maintaining best routes to the networks and servers. Route and path metrics may be combined to determine paths from access switches to egress switches connected to the external network.

Distributed connection-oriented services for switched communication networks

Method and apparatus providing connection-oriented services for packet switched data communications networks. Directory services include distributed discovery of MAC addresses and protocol alias addresses. Topology services include a link state topology exchange among switches, which provides each switch with a complete topology graph of the network. This enables an access switch receiving a data packet to determine a complete path from a source end system to a destination end system. Another service includes resolution of broadcast frames to unicast frames, in order to reduce the amount of broadcast traffic. Policy restrictions may be applied prior to connection setup. Path determination services enable multiple paths from a source to a destination. Connection management includes source routed mapping of connections on the desired path. A distributed call rerouting service is provided wherein if a link on an active path fails, each switch receives a topology change notification and unmaps any connection involving the failed link. A broadcast/unknown service provides restricted flooding of nonresolvable packets. Furthermore, connection-oriented switching is provided based on the source and destination MAC addresses as a connection identifier. Still further, resolution of networks outside the switch domain is enabled by access switches listening for network and server route advertisements and maintaining best routes to said networks and servers. The best route metrics may be combined with best path metrics to determine a path from a first access switch to an egress switch connected to the external network.

Distributed connection-oriented services for switched communications networks

An interconnecting apparatus includes one or more interfaces. Each interface connects to a network. The interconnecting apparatus interconnects the networks attached to the interfaces. The device utilizes distributed autonomous forwarding engines on each interface in that each interface has a forwarding engine corresponding to it. Each forwarding engine only knows the configuration information and how to receive and transmit packets on the one interface to which it corresponds. Each forwarding engine acts independently to process packets, yet each interacts together to collectively provide packet forwarding which is protocol independent, interface independent, and scalable.

Network interconnecting apparatus having a separate forwarding engine

Distributed connection-oriented services for switched communications

An object-oriented architecture for network layer routing is provided which distributes function and system behavior into autonomous router objects. By distributing these functionalities into each object, the services and data normally external to the object are imbedded or accessible within the object itself. In another sense, some objects are distributed across the network; e.g., a separate forwarding engine is provided at each network interface. In a preferred embodiment, each object has: (1) common, protocol-independent functions that are shared by all objects of that class; (2) their own configuration information; (3) accessibility through a router resource object for instantiation and control; (4) automatic persistence in NVRAM; (5) remote management capabilities; and (6) text names for navigation of a resource tree as a file system. These capabilities are in every object regardless of the specific protocol or application. This ensures a common architecture among many different systems/router components, a common method of control internally, a consistent order of instantiation and a common functional behavior.

Distributed autonomous object architectures for network layer routing

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Amherst, NH, United States of America

Kevin Yohe