Patents Assigned to Cisco Systems, Incorporated
  • Patent number: 6222822
    Abstract: Method and system for tracking transient errors and controlling data traffic in a high speed packet switching network node. The traffic exits each node through a transmit queue per connection between end users. The queue is monitored at both queue level through a threshold based mechanism (53) and a control of time activity mechanism (55). If trouble is detected by any one of these mechanisms, the queue packet admission is momentarily barred. To that end, a Line Resources Manager (LRM) provides queue threshold and time-out references and keeps monitoring the node global buffering memory available. If required, the LRM may also report to Network Management facilities for possible rerouting of the traffic.
    Type: Grant
    Filed: March 31, 1997
    Date of Patent: April 24, 2001
    Assignee: Cisco Systems, Incorporated
    Inventors: Pierre Gerardin, Patrick Massi, Victor Spagnol
  • Patent number: 5509006
    Abstract: A device for switching packets at high speed. For each packet, the A device matches packet data with protocols, to determine how to switch the packet. Matching of data with protocols is highly parallel; the device simultaneously retrieves a data byte, compares a data byte with a protocol byte, tests a comparison result, and executes a processor instruction. A switching engine having a comparator and a decision tree memory. The comparator includes three outputs for indicating a comparison result (less-than, equal-to, or greater-than). The tree memory includes three corresponding banks of addressable memory. Each memory location comprises an entry for a next location, an entry for a next protocol byte, and an entry for a processor instruction. A set of protocol tests are assembled into the tree memory, and a set of routing tables are dynamically generated into the tree memory.
    Type: Grant
    Filed: April 18, 1994
    Date of Patent: April 16, 1996
    Assignee: Cisco Systems Incorporated
    Inventors: Bruce A. Wilford, Bruce Sherry, David Tsiang, Anthony Li
  • Patent number: 5473599
    Abstract: A system and protocol are provided for routing data packets from a host on a LAN through a virtual address belonging to a group of routers. The host is configured to point to the virtual address so that the packets it sends out of its LAN are always directed to a virtual router which may be any one of the group of routers. An active router in the group of routers emulates the virtual router. A standby router, also from the group of routers, backs up the active router so that if the active router becomes inoperative, the standby router automatically begins emulating the virtual router. The host router does not know which router from the group is actually handling the data packets it sends. If the standby router becomes inoperative or takes over for the active router, other routers in the group hold an election to determine which of them should take over for the standby router.
    Type: Grant
    Filed: April 22, 1994
    Date of Patent: December 5, 1995
    Assignee: Cisco Systems, Incorporated
    Inventors: Anthony J. Li, Bruce A. Cole