Cisco Technology, Inc.

Cisco Systems Inc.

Mahesh Chellappa

Krishna Sundaresan

Chandrasekar Krishnamurthy

Daniel Cauchy

Carlos M Pignataro

Stephen Eugene Morrow

A method and system for optimizing link aggregation usage during failures is disclosed. The method and system are deployed in a network having a data plane in which data traffic flows between nodes coupled by a link formed by an aggregation of a number of individual connections (e.g., an IMA comprising a plurality of Tor Elines, MPLS transport LSPs, ATM VPCs, etc.) and a control plane for controlling data traffic. The method includes communicating a bandwidth change on the link corresponding to the failure to the control plane. Flapping of the link is deterred. A component of the traffic is released based on a configured policy.

Method and system for optimizing link aggregation usage during failures

A method for enhanced crankback handling in a multi-peer group network. The method includes receiving a first connection request from a node of a first peer group. Upon detection of a call failure within the second peer group, a crankback is transmitted from the second peer group to the first peer group. The crankback specifies a blocked interface at a first link between the first peer group and the second peer group. The crankback is transmitted from a node of the second peer group. A second connection request is subsequently received from the node of the first peer group. The second connection request uses a second link to the second peer group that avoids the call failure.

Method and system for enhancing crankback handling in multi-peer group networks

A system and method for providing link, node, and PG policy based routing in PNNI based ATM networks is disclosed. A computer implemented method signals and routes a call in the network. Upon detecting the call's arrival, its service request is accessed. Upon determining that the service request relates to an attribute of a link, a routing path is sought that conforms to the service request, as by accessing information relating to the routing path and comparing the information to the service request. A conforming routing path is selected, and the call is routed via that path. A computer implemented method advertises an attribute of links, nodes, policies, etc. Data relating to the route's attribute can be provided to a node as a GAT IE component of a PNNI signaling setup message for multi-peer group networks, and advertised using PTSEs within a peer group.

System and method for providing link, node and PG policy based routing in PNNI based ATM networks

A method is described that involves updating an understanding of an ATM PNNI network after the reception of PTSE information. The PTSE information has SIG information that describes bandwidth which has been allocated to specific priority levels of a bandwidth resource. The bandwidth resource is within the ATM PNNI network. Then, determining a path through the network for a requested connection. The path is determined in light of the updated understanding. The requested connection has a priority level, wherein the path may result in one or more connections being dropped in order to allow bandwidth for the requested connection. Each of the dropped connections has a lower priority level than the priority level of the requested connection.

Method and apparatus for true priority based connection establishment within a PNNI ATM network

An embodiment of the invention provides a method for specifying preferred routes for SPVCs across multi-peer group PNNI networks and AINI links. A preferred route for a network connection through a network having a plurality of nodes, organized hierarchically into a plurality of peer groups, is determined. The preferred route is associated with a preferred route identifier. The preferred route identifier is carried in the PNNI SETUP message and is used to link a preferred route database in the source node with the entry border nodes of remote peer groups for a single SPVC. The entry border node of each peer group establishes a connection over a static route corresponding to the preferred route identifier. For one embodiment the preferred route identifier is carried in a generic application transport information element of the PNNI signaling SETUP message, providing a scalable preferred routing capability for SPVCs across multi-peer group PNNI networks.

Method to enhance routing control in PNNI networks

A system and method are disclosed for dividing a network into clock partitions to limit the overhead created by transmitting clock sources. A clock partition can be implemented through several methods. A first method turns off the clock topology exchange on ports connected to the nodes outside the partition. A second method appends a four-byte partition identifier to network clock distribution protocol (NCDP) messages. A third method uses private network-network interface (PNNI) peer group identification to determine the clock partition group.

Scaling dynamic clock distribution for large service provider networks

A first route is associated with a first channel of two or more channels in a first dense wavelength division multiplex (DWDM) link. A second route is associated with a second channel of the two or more channels in the first dense wavelength division multiplex (DWDM) link. A third route is associated with a third channel of two or more channels in a second dense wavelength division multiplex (DWDM) link. The first route, the second route and the third route provide similar connections. The first DWDM link is different from the second DWDM link. The third route is preselected as an alternate diverse route for a connection through the first route.

Method and system for diverse route computation

A method for automatically reconfiguring a soft permanent virtual circuit (SPVC) source endpoint in a PNNI ATM network, in response to an address change at a destination endpoint, by encoding the address change information in a SIG field in a PNNI topology state element within a PNNI topology state packet.

Method and apparatus for efficient SPVC destination endpoint address change

A method to provide actual network connection routing cost for use in connection grooming is disclosed for one embodiment. A setup message is transmitted from a source network node, through one or more intermediate nodes, to a destination node. A connect message, in acknowledgement of the setup message, is transmitted from the destination node, through the one or more intermediate nodes, to the source node to establish a network connection. The connect message includes an actual routing cost field. For one embodiment, an actual routing cost field is carried in a generic application transport (GAT) information element (IE) of a PNNI CONNECT message. The actual routing cost field is updated at every node as each link is traversed from the destination node to the source node. The accumulated routing cost in the GAT IE represents the actual routing cost of the SPVC, which the source node uses for connection grooming.

Growing community of inventors

San Jose, CA, United States of America

Mahesh Chellappa