Cabletron Systems, Inc.

Enterasys Networks, Inc.

Other

Enterasys, Inc.

Chris Oliver

Kurt A Dobbins

Brendan J Fee

David L Cullerot

Michael Skubisz

Kevin Yohe

Theodore C Len

Thomas A Grant

Philip Andlauer

David H Bahi

Laura Kane

David Ruffen

Dan Hullette

Roger H Dev

Jason Jeffords

Phil Andlauer

Andy Grimes

Tom Parker

Bruce Nutbrown

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

Distributed connection-oriented services for switched communications

Apparatus and method for establishing 'virtual connections' through a packet switched data communications network, the network including a plurality of end systems and switches connected by links. Each end system has a unique physical layer address and each switch has a connection database of valid connections between different ports on the switch and a switching mechanism for establishing temporary connections. Each switch is registered with a connection server such that, prior to transmission of a connectionless datagram from a first end system to a second end system, a path of valid connections through one or more switches from the first end system to the second end system is determined by configuring the connection table of each switch on the path with a connection identifier identified by the physical layer addresses of the first and second end systems, and wherein the data packet remains as a connectionless datagram. In other aspects, an improved method is providing for allocating bandwidth among competing devices requesting access to a bandwidth limited shared resource (e.g., the previously defined switch), and to a search method for making a best path determination through the network based on a number of constraints.

Method of transmitting data packets in a packet switched communications

Apparatus and method for establishing 'virtual connections' through a packet switched data communications network, the network including a plurality of end systems and switches connected by links. Each end system has a unique physical layer address and each switch has a connection database of valid connections between different ports on the switch and a switching mechanism for establishing temporary connections. Each switch is registered with a connection server such that, prior to transmission of a connectionsless datagram from a first end system to a second end system, a path of valid remains as a connectionless datagram. In other aspects, an improved method is provided for allocating bandwidth among competing devices requesting access to a bandwidth limited shared resource (e.g., the previously defined switch), and to a search method for making a best path determination through the network based on a number of constraints.

System and method for allocating a shared resource among competing

A fault tolerant system management bus architecture for a networking chassis includes a primary path for transmission of system management information and a secondary path for transmission of system management information in the event of failure of the primary path. The primary path includes a first microprocessor controller, coupled between the first system management bus and the processor located on a networking module. The secondary path for transmission of system management information includes a second microprocessor controller system and a dual-port memory. The second microprocessor control system is coupled to the second system management bus and to the dual-port memory. The dual-port memory is also coupled to the processor located on the networking module. The dual-port memory provides the interface between the CPU in the networking module and the second microprocessor control system, thus providing isolation and allowing the memory to be accessible by either processor. Environmental information and module identification information are stored in the dual-port memory. In the event of failure of the primary transmission path, the environmental information and module identification information can be accessed and transmitted over the backup transmission path.

Chassis fault tolerant system management bus architecture for a

Network having secure fast packet switching and guaranteed quality of

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Rochester, NH, United States of America

Chris Oliver