Cisco Technology, Inc.

International Business Machines Corporation

Russell Eugene Gardo

Jimmy Philip Ervin

Charles Allen Carriker

Praveen Bhagwatula

Cedell Adam Alexander, Jr

Sonia Kiang Rovner

Brahmanand Kumar Gorti

Thomas Eric Ryle

Sanjeev Debdutta Rampal

Steven J Faulkner

Thomas E Black, Jr

James Scott Alexander

Olen Lee Stokes, Jr

Norman Eugene Cox

Stephen W Piucci

A method and system for emulating an Ethernet link over a Sonet path to provide link integrity is disclosed. The method generally includes receiving an error code at a local Ethernet port upon detection of a link failure at a remote Ethernet port. The error code is received over a Sonet path in a Sonet path overhead. If the error code is still present after a specified period of time, the local Ethernet port is disabled. Methods for providing link stability and link availability are also disclosed.

Method and system for emulating an ethernet link over a sonet path

A method for providing inter-ring protection in shared packet rings includes identifying an active node which is connected to a ring interconnect node on the same ring as the active node and connected to a peer node on a different ring with a ring interconnecting link. When the active node is in active mode and receives notification of a failure of the ring interconnecting link or peer node, the active node sends a message to the ring interconnect node so that the ring interconnect node switches from standby mode to active mode. The active node is then changed to standby mode.

Inter-ring protection for shared packet rings

A method for preventing loops in a ring topology of a computer network is disclosed. The method includes receiving a packet at a node on a shared packet ring and inserting a header containing an ID identifying the node at which the packet was received on the ring as an originating node. The packet is forwarded onto the ring and the ID is checked when received on a node. The packet is dropped if the ID identifies the node as the originating node.

Method and system for providing a loop-free ring topology

In a data communication internetwork including a source station, an end station, and a default router for the source station, a default communication path including the default router is defined between the source station and the destination station. During operation of the data communication internetwork, a shortcut data communication path by passing the default router is established between the source station and the destination station, such that data packets transmitted by the source station are not received by the default router. After the shortcut communication path has been established, a control frame containing source-route information regarding the source station is transmitted to the router, and the source-route information is stored at the router. In this manner, the default router can efficiently direct data packets to the source station and facilitate the establishment of shortcut communication paths terminating at the source station even though the default router is bypassed by a shortcut communication path.

Method and system within a computer network for maintaining source-route information at a router bypassed by shortcut communication

A method is implemented by which a Logical IP subnetwork attached (LIS) Next Hop Resolution Protocol (NHRP) client or an Emulated LAN (ELAN) subnetwork attached NHRP client in an Asynchronous Transfer Mode (ATM) network can send data to a destination LAN Emulation Client (LEC) on a different ISO layer-3 subnetwork via a data-direct Virtual Channel Connection. The method enables such a IP subnetwork attached NHRP clients to obtain the ATM address corresponding to the destination station by using the vendor-private extension within an NHRP packet. The NHRP client uses the ATM address to build a data-direct VCC over which it unicasts data bound for the destination station. The NHRP client appears to the destination LEC as any other LEC on its ELAN would appear.

Next hop resolution protocol cut-through to LANs

Growing community of inventors

Raleigh, NC, United States of America

Russell Eugene Gardo