Patent application number | Description | Published |
20110044330 | Link State Identifier Collision Handling - Methods and apparatus for a network element to handle LSID collisions to prevent different LSAs associated with different routes from sharing the same LSID. According to one embodiment, responsive to determining that a tentative LSID that is generated for a first route that is being added collides with an LSID that is assigned to an LSA for a second route, and that one of the first and second routes is a host route, the host route is suppressed. If the first route is the host route, suppressing includes not originating an LSA for the first route. If the second route is the host route, suppressing includes purging the LSA for the second route and not originating an LSA for the second route. Although the host route is suppressed, network reachability of the range subsuming the host route is provided through the route that is not the host route. | 02-24-2011 |
20130003731 | Link State Identifier Collision Handling - Methods and apparatus for a network element to handle LSID collisions to prevent different LSAs associated with different routes from sharing the same LSID. According to one embodiment, responsive to determining that a tentative LSID that is generated for a first route that is being added collides with an LSID that is assigned to an LSA for a second route, and that one of the first and second routes is a host route, the host route is suppressed. If the first route is the host route, suppressing includes not originating an LSA for the first route. If the second route is the host route, suppressing includes purging the LSA for the second route and not originating an LSA for the second route. Although the host route is suppressed, network reachability of the range subsuming the host route is provided through the route that is not the host route. | 01-03-2013 |
20130024684 | ENHANCED APPROACH FOR TRANSMISSION CONTROL PROTOCOL AUTHENTICATION OPTION (TCP-AO) WITH KEY MANAGEMENT PROTOCOLS (KMPS) - A network element supports Transmission Control Protocol Authentication Option (TCP-AO) with a Key Management Protocol (KMP) to authenticate TCP segments over a TCP session. The network element negotiates multiple traffic keys to authenticate TCP segments over a TCP session with a peer network element, and protects the TCP session with the negotiated traffic keys. | 01-24-2013 |
20140211800 | Accelerated MAC address resolution for IPv6 traffic with IS-IS Protocol - A method is executed by a router for improved Intermediate System to Intermediate System (IS-IS) protocol and Neighbor Discovery (ND) protocol execution to avoid dropped data traffic caused by Media Access Control (MAC) address resolution for next hops of routes determined by the IS-IS protocol. An IS-IS adjacency is established between the router and a neighbor router over a link, where a MAC address for the neighbor router is received from the neighbor router. A routing information base (RIB) is updated to include the neighbor router as a next hop for at least one destination address by the IS-IS process. The MAC address of the neighbor router is provided to an ND process to update the RIB, a forwarding information base (FIB) or L2 forwarding table of at least one line card of the router to include the MAC address of the neighbor router in response to the providing of the MAC address to the ND process. | 07-31-2014 |
20140233738 | Mechanism for Co-Ordinated Authentication Key Transition for IS-IS Protocol - An automated key transition method is executed by a node in a network. The network includes a set of nodes utilizing a current key identifier provided by a group key management server or provisioned manually. A key identifier specifies an authentication protocol and an authentication key for use in the authentication of intermediate-system to intermediate-system (IS-IS) protocol data units. The method includes receiving a message from the group key management server that includes a most recent key field to replace the current key identifier, advertising the most recent key identifier to all reachable nodes, verifying whether all reachable nodes have advertised the most recent key identifier, continuing authentication using the current key identifier until all reachable nodes have been verified to advertise the most recent key identifier, and switching authentication to use the most recent key identifier upon verification that all reachable nodes have advertised the most recent key identifier. | 08-21-2014 |
20150263932 | PROCEDURE TO IDENTIFY MULTI-HOMED PREFIXES FOR IS-IS LFA - A method of a network device identifies multi-homed prefixes in an intermediate system-intermediate system (IS-IS) area or IS-IS domain during shortest path first (SPF) computation for use in a loop free alternate (LFA) computation. The method and network device select a next node in a shortest path tree (SPT) and determine a set of prefixes associated with the selected node in the SPT. A next prefix from the set of prefixes of the selected node is selected and a check is made whether the selected prefix exists in the local RIB associated with another node of a same level, then the selected prefix is marked as a multi-homed prefix in the local RIB. A check is made whether all prefixes associated with the selected node are processed and whether all nodes in the SPT have been processed, before downloading the local RIB to a global RIB. | 09-17-2015 |
20150271052 | Procedure to Add Alternate Paths for IS-IS Default Route - A method is implemented by a network device to determine loop free alternatives (LFA) for each next hop in a default route to border nodes of a level 1 intermediate system—intermediate system (IS-IS) area of the network device. The method selects a next next-hop for the default route and looks up a corresponding border node for the selected next-hop in a local routing information base (RIB). A next next-hop of the corresponding border node is selected. A check is made whether the selected next-hop of the corresponding border node is the same as selected next-hop of default route. Then an LFA of the selected next-hop of the corresponding border node is assigned as LFA of the selected next-hop of the default route. | 09-24-2015 |
20150271056 | OPTIMIZED APPROACH TO IS-IS lFA COMPUTATION WITH PARALLEL LINKS - A method is executed by a network device to a calculate loop free alternative (LFA) for each node in an intermediate system-intermediate system (IS-IS) area or IS-IS domain where the network device is connected with other nodes via multiple parallel links. The method includes a shortest path first (SPF) computation of the primary paths for the network device that tracks directly connected links from each node in the IS-IS area or IS-IS domain to the network device which is a source node for the SPF. These tracked links can then be utilized in subsequent LFA computations to avoid unnecessary calculations. | 09-24-2015 |
20150271059 | BETTER ALTERNATE PATHS FOR MULTI HOMED IS-IS PREFIXES - A method is executed by a network device to determine a loop free alternate (LFA) for a multi-homed prefix in an IS-IS area or IS-IS domain. The method includes selecting a next node from the IS-IS area or the IS-IS domain and selecting a next prefix for the selected node. A check is made whether the selected prefix is a multi-homed prefix (MHP). A check is made whether a shortest path first (SPF) cost of the selected node and cost to the selected prefix is equal to an SPF cost of the selected prefix, whether a next hop of selected prefix is same as next hop of selected node, and whether a LFA next hop of the selected node is better protection than a current next hop protection of the selected prefix and the LFA next hop of the selected node is then inherited for the selected prefix. | 09-24-2015 |