Abstract: A packet network device, such as a router or switch, includes functionality that operates to receive network traffic, process the traffic as needed and to forward the traffic to its destination. Additionally, each router includes a weighted equal cost multipath routing function that operates to identify equal cost paths over which to forward the network traffic, to calculate a path weighting that is dependent upon the path bandwidth and to forward the traffic ingressing to it over each of the equal cost paths according to the calculated path weighting.

Abstract: A packet network device includes a packet network processor memory system for storing information used to process and forward packets of information in and through the network device. The information is included in look-up tables whose entries can be mapped either horizontally or vertically into the memory system. In the event that the entries are mapped horizontally, a complete entry can be access at a single memory location and in the event that the entries are mapped vertically, the entries can be accessed at one or more memory locations.

Abstract: A packet network device, such as a router or switch, includes functionality that operates to receive network traffic, process the traffic as needed and to forward the traffic to its destination. Additionally, each router includes a weighted equal cost multipath routing function that operates to identify equal cost paths over which to forward the network traffic, to calculate a path weighting that is dependent upon the path bandwidth and to forward the traffic ingressing to it over each of the equal cost paths according to the calculated path weighting.

Abstract: A packet network device includes a control module, one or more line cards each one or which includes a plurality of ingress and egress ports, and each of the ingress and egress ports are connected to external network links. The line cards maintain forwarding tables and include functionality that employs information in the forwarding tables to determine how incoming packets of information should be forwarded. The control module includes functionality that operates to learn reachability information about other devices connected to the network that are and to use this reachability information to update forwarding tables maintained on the line cards. The control module also includes an enhance ARP functionality that operates in cooperation with standard ARP functionality and other network protocols included on the control module to diminish the amount of data lost in the event that a link connected to one of the egress ports fails.

Abstract: A plurality of network devices such as routers are included in an instance of a spanning tree. The network device creates a ring context on a port that it identifies as both a blocking port and configured to run a spanning tree protocol. The ring context can be comprised of a region name, an STP domain name or a spanning tree instance. The network device transmits a ring discover message for the ring context over a forwarding port and determines that a ring exists when it receives the message at a blocking port. The network device subsequently transmits a reverse ring discover message from its blocking port which includes the status of the discovered ring to the members of the ring topology.

Abstract: A packet switch collects configuration information on the peer devices to which it connects. Peer devices that are IP (Internet Protocol) telephones are sensed. Such devices may also bridge packets to a connected device such as a computer, but with a bridge capability that cannot handle large broadcast storms on the network. The packet switch uses the configuration information to limit broadcast storms on its ports connected to the relatively fragile IP telephones/bridges. This can prevent broadcast storms from disrupting calls on the IP telephones connected to the packet switch.

Abstract: A network switch is comprised of a control processor and one or more line cards. The control processor includes functionality to register interest with a hypervisor, operating in conjunction with a network host connected to the switch, in data object attributes maintained on the network host by the hypervisor. The hypervisor associated with the network host sends changes in the host attributes to the switch which the switch maintains in a listing of attributes. The switch traps and copies particular packets to the switch control processor where a provisioning function operates on the attribute information in the list with source information included in the packet header in order to configure a forwarding table on the line card.

Abstract: A stacked chassis comprising multiple physical switch/router chassis operates without any special stacking hardware or stacking channels. Instead, a stacking LAG is installed between front-end switch ports on the stacked chassis. The chassis controllers negotiate a master, which controls operation of all chassis in the stack. A stacked-chassis-wide port numbering scheme is used to distribute information to all line cards in the system. Each line card processes the information to distill physical-chassis significant information for operation of that chassis in the stack.

Abstract: Methods and apparatus for serial channel operation are disclosed. An N+1-level signaling scheme is used to transmit N staggered but overlapping NRZ sub-sequences concurrently on a serial channel. Each sequence has a bit rate R and an essential bandwidth of R Hz. The combined bit rate of the channel is N×R, but due to a lack of correlation between the sub-sequences, the essential bandwidth remains approximately R Hz. The signaling scheme also contains redundancy that allows some errors to be detected and/or corrected. Other embodiments are also described and claimed.

Abstract: Systems, methods, and apparatuses are provided that enable streaming of ATM cells between a transmit/receive data processing application and a transmission convergence function. Data to be segmented into an ATM cell is received at a SAR engine, and provided to a transmission convergence function, with the first cells transmitted to the transmission convergence function before the SAR function receives an end-of-packet indication from the optimization engine. Data received at a transmission convergence function is placed in a received packet queue at the SAR function, with packets provided to an application after a start-of-packet indication is received, and before an end-of-packet indication is received, at the SAR function.

Abstract: A modular packet network device has a chassis in which multiple logic cards mate to the front side of an electrical signaling backplane. Logic power for the logic cards is supplied from a group of power converter cards that convert primary power to the logic voltages required by the logic cards. The power converter cards lie in a separate cooling path behind the backplane. Advantages achieved in at least some of the embodiments include removing primary power planes from the signaling backplane or portion of the backplane, providing redundant, upgradeable power modules whose individual failure does not cause logic card failure, and providing cool air to power converter circuits that would be subject to only heated air if located on the logic cards. Other embodiments are also described and claimed.

Abstract: A distributed-forwarding router platform contains a master and a standby route processing manager (RPM). The master RPM uses dynamic internal routing codes to facilitate the replication of multicast packets within the router. As internal routing codes are assigned, the assignments are shared with the standby RPM. Should the standby RPM have to take over as the master RPM, the new master consults the internal routing codes assigned by the previous master as the new master builds multicast state, insuring that the internal routing codes the new master assigns are consistent with those used by the prior master. This allows the multicast forwarding plane to remain available during RPM failover, without a shutdown or unstable period while the new master RPM propagates internal routing codes. Other embodiments are also described and claimed.

Abstract: A stacked chassis comprising multiple physical switch/router chassis operates without any special stacking hardware or stacking channels. Instead, a stacking LAG is installed between front-end switch ports on the stacked chassis. The chassis controllers negotiate a master, which controls operation of all chassis in the stack. A stacked-chassis-wide port numbering scheme is used to distribute information to all line cards in the system. Each line card processes the information to distill physical-chassis significant information for operation of that chassis in the stack.

Abstract: Two network switches are configured in a stacked relationship to each other and include link aggregation sub-layer functionality. Switching tables are programmed on each switch with information used to forward packets ingressing to them over a redundant LAG that is identified in the switching table by a port that is a member of the redundant LAG.

Abstract: A LAN includes a router that is connected to two or more racks of servers and each of the servers can support a plurality of virtual machines. The router is configured to forward data packets based on IP destination addresses or based on destination MAC addresses and builds and maintains forwarding tables in support of data packet forwarding in the layer 3 and the layer 2 network environment. In support of layer 2 forwarding, the router builds and maintains an aggregated MAC switching table that is comprise of a subset of the table entries typically needed to switch packets to their destination, and in support of layer 3 forwarding, the router or switch builds and maintains an aggregated ARP forwarding table that is comprised of a subset of the table entries typically needed to forward packets to their destination.

Abstract: Methods and apparatus for serial channel operation are disclosed. An N+1-level signaling scheme is used to transmit N staggered but overlapping NRZ sub-sequences concurrently on a serial channel. Each sequence has a bit rate R and an essential bandwidth of R Hz. The combined bit rate of the channel is N×R, but due to a lack of correlation between the sub-sequences, the essential bandwidth remains approximately R Hz. The signaling scheme also contains redundancy that allows some errors to be detected and/or corrected. Other embodiments are also described and claimed.

Abstract: A stacked chassis comprising multiple physical switch/router chassis operates without any special stacking hardware or stacking channels. Instead, a stacking LAG is installed between front-end switch ports on the stacked chassis. The chassis controllers negotiate a master, which controls operation of all chassis in the stack. A stacked-chassis-wide port numbering scheme is used to distribute information to all line cards in the system. Each line card processes the information to distill physical-chassis significant information for operation of that chassis in the stack.

Abstract: A packet switch contains a link state group manager that forms supergroups from multiple link aggregations. The link state group manager collects state information for the link aggregations in a supergroup, and uses state criteria to determine whether the link aggregations are allowed to be up, as a supergroup, for data traffic. This allows a supergroup of links to only come up when it meets a minimum performance criteria, with traffic routed around the supergroup when the supergroup cannot meet the minimum performance criteria, even if some link aggregations in the group are functional.

Abstract: A packet network device, such as a router or switch, includes functionality that operates to receive network traffic, process the traffic as needed and to forward the traffic to its destination. Additionally, each router includes a weighted equal cost multipath routing function that operates to identify equal cost paths over which to forward the network traffic, to calculate a path weighting that is dependent upon the path bandwidth and to forward the traffic ingressing to it over each of the equal cost paths according to the calculated path weighting.

Abstract: A packet network system, such as an autonomous system, includes a plurality of packet network devices some of which are edge routers and some of which are core routers. Each of the edge and core routers include functionality that operates to receive network traffic, process the traffic as needed and to forward the traffic to its destination. Additionally, each router includes a traffic distribution function that operates to calculate path bandwidths for all of the paths over which the traffic can be forwarding through the system and to use the volume of traffic ingressing to the system, link utilization information and the calculated path bandwidth to redistribute the traffic in the system such that traffic loss in the system in minimized.