Brocade Communications Systems, Inc.

Arris Enterprises LLC

Wing-Keung Adam Yeung

Ajeer Salil Pudiyapura

Mehul Dholakia

Jian S Liu

Nitin Jain

Hasnain Karampurwala

Reshma Sudarshan

Ganesan Velrajan

Tejaswini Chadaga

Senthil Kumar Nagappan

Sabarivel Sakthivel

Techniques for intelligent designated forwarder (DF) and master router selection (for router redundancy) are provided. In one embodiment, a network router that is part of a set of network routers connected to a common LAN segment can retrieve a priority value adapted for use by the network router in electing a DF for multicast traffic. The network router can further check for the presence or absence of one or more routes to one or more multicast sources in a routing table of the network router. The network router can then modify the priority value based on the presence or the absence of the one or more routes and can transmit a multicast routing protocol control packet including the modified first priority value to one or more other network routers in the set of network routers.

Intelligent selection of a designated forwarder and a master router for router redundancy

One embodiment of the present invention provides a switch. The switch includes a multicast management module, a storage module, and a recovery module. During operation, the multicast management module represents multicast information from one or more entries of a multicast data structure in a way that the switch can derive its multicast states from the multicast information. The storage module stores the multicast information in a recovery file in a local persistent storage device. If the switch reboots, the recovery module restores the multicast states of the switch from the multicast information in the recovery file.

Techniques to restore multicast data plane from persistent storage

Techniques for customizing forwarding decisions in a network device via a hardware lookup table result are provided. In one embodiment, a network processor of the network device can perform a lookup into a lookup table based on one or more sections of a received packet. The network processor can then determine, based on the lookup, an entry in the lookup table and retrieve, using a pointer included in the lookup table entry, a mode value from a results table. The mode value can identify an operational flow (e.g., a series of forwarding decisions) to be carried out by the network processor for forwarding the received packet.

Techniques for customizing forwarding decisions via a hardware lookup result

Techniques that enable a network device such as a router to provide multicast routing services without interruption, even in the event of a switchover. An incremental updates technique is used to synchronize multicast information maintained by a first processor and multicast information maintained by a second processor. The first processor may be a management processor operating in active mode in a network device and the second processor may be a management processor operating in standby mode in the network device. The second processor may also be a processor on a linecard of the network device.

Synchronization of multicast information using incremental updates

In embodiments of the present invention, multicast traffic is simultaneously routed via all switches participating in the trunk (can be referred to as partner switches). A respective partner switch synchronizes the local multicast state information with all other partner switches. For a respective multicast group, a plurality of partner switches can be the part of the corresponding multicast distribution tree and obtain multicast traffic from uplink sources. For the multicast group, only one partner switch is elected as the primary forwarder which forwards the multicast traffic via the trunk. Another partner switch can become the primary forwarder for the multicast traffic of another multicast group and provide load sharing of multicast traffic between partner switches. Furthermore, because the partner switches have the multicast traffic and state readily available, in the event of a switch or link failure to the primary forwarder, another partner switch can readily become the primary forwarder.

IP multicast over multi-chassis trunk

In a network device comprising redundant management processors and one or more linecard processors situated on one or more linecards, a linecard processor maintains multicast information that is synchronized with multicast information, or a portion thereof, maintained by an active management processor. When a switchover is performed due to which a previous standby management processor becomes the new active management processor, the switchover is performed without interrupting any multicast routing services provided by the network device. For example, a switchover may be performed in order to upgrade a linecard processor to a new software version.

Synchronizing multicast information for linecards

Techniques for synchronizing data object instances between applications/processes in an efficient manner. In one set of embodiments, the techniques described herein can be implemented in one or more network routers to synchronize data between a process running on an active management processor and a process running on a standby management processor, thereby facilitating features such as non-stop routing (NSR).

Techniques for synchronizing application object instances

Techniques that enable a network device such as a router to provide multicast routing services without interruption. Techniques are provided for using bicasting to synchronize multicast information maintained by a first processor and multicast information maintained by a second processor. A multicast protocol related event of packet is sent to both a first processor operating in active mode and a second processor operating in standby mode. Each processor then updates its multicast information based upon the bicasted event or packet.

Growing community of inventors

Pleasanton, CA, United States of America

Wing-Keung Adam Yeung