Cisco Technology, Inc.

Arista Networks, Inc.

Madhu Sudan

Hemant Singh

Ralph Droms

William Beebee

John T Chapman

Chad Mikkelson

Raman Shankara Krishnan

Sanjeev Hemantkumar Desai

Rajesh Kumar Semwal

Amit Dattatray Ranpise

Nitin Singh

Joshua B Littlefield

Bernard Ernst Volz

Shengyou Zeng

Ciprian Pompiliu Popoviciu

Anthony Lee Hain

Salman Asadullah

Adeel Ahmed

Techniques for implementing neighbor equivalence groups on a network device are provided, where a neighbor equivalence group is a group of peers of the network device that communicate identical control plane state information for a given network protocol to the network device. In the context of Border Gateway Protocol (BGP), these techniques can include (1) creating, by the network device, a neighbor equivalence group for a set of BGP peers that advertise the same BGP paths to the device, (2) maintaining, by the network device, a single path database for the neighbor equivalence group (rather than one path database for each BGP peer in the group), and (3) immediately processing by the network device, BGP path update/withdrawal messages received from any of the BGP peers in the group against the single path database, without waiting for the same message to be received from every peer.

Neighbor equivalence groups

In one embodiment, methods are described for recovering lost customer premises equipment (CPE) information on a cable modem termination system (CMTS) in the presence of only Dynamic Host Control Protocol Version 6 (DHCPv6) CONFIRM. A CMTS purges routing information for an Internet Protocol Version 6 (IPv6) node, such as a CPE router, in response to detecting an interface reset for the IPv6 node. IPv6 addresses and prefixes information for the IPv6 node is gleaned from a DHCPv6 CONFIRM message received from the IPv6 node. By sending portions of the IPv6 addresses and prefixes information within a DHCPv6 LEASEQUERY message, a DHCPv6 CONFIRM message with an embedded DHCPv6 LEASEQUERY message, or a DHCPv6 CONFIRM message with an Interface-ID option, a reply message can be received that contains the purged routing information for the IPv6 node.

Recovering lost device information in cable networks

A method is provided in one example and includes determining that an access concentrator has lost customer premise equipment information. The method also includes obtaining the customer premise equipment information that is lost by evaluating Neighbor Discovery data and dynamic host configuration protocol version six (DHCPv6) query data. In more specific implementations, the method may include communicating a Bulk Leasequery message; receiving a response to the Bulk Leasequery message; and filtering out cable modem identifiers from the response to the Bulk Leasequery message.

System and method for recovery of customer premise equipment information on an access concentrator

A network processing device is configured to receive a configuration message from a host device and forward the configuration message to a server. The configuration message can be configured to request the server assign an Internet Protocol (IP) address to the host device. The network processing device can be configured to send at least one probe message to the host device responsive to receiving the configuration message. The network processing device can be configured to determine whether the host device intends to continue utilizing a previously assigned IP address in addition to the IP address requested by the configuration message based, at least in part, on any responses to the at least one probe message received from the host device.

Detection and support of a dual-stack capable host

Techniques are provided herein for receiving synchronization messages at a second network device that is in a hot standby configuration from a first network device that is maintaining Internet Protocol version 6 (IPv6) state machines for one or more neighbor devices. The synchronization messages are configured to indicate an IPv6 state for each state machine maintained in the first network device. An IPv6 state for corresponding state machines is updated in the second network device based on the synchronization messages such that the IPv6 states in the second network device allows the second network device to actively process IPv6 traffic for the one or more neighbor devices upon traffic switchover from the first network device to the second network device without restarting the corresponding IPv6 state machine associated with each of the one or more neighbor devices in the second network device. The roles of the first and second device with respect to active and standby state are reversed after a switchover.

Hot standby neighbor discovery protocol for internet protocol version 6

An apparatus may include a port to receive a ranging request from a cable modem and a processor in communication with the port. The processor may assign a service identifier to the cable modem, match the service identifier with a link layer address of the cable modem, receive a router advertisement and comparing the source link layer address from the router advertisement to the link layer address of the cable modem, and determine if the link layer address of the cable modem is the same as the source link layer address.

Use of IPv6 in access networks

A CMTS or other data aggregation component having a DHCPv6 relay agent extracts a Media Access Control (MAC) address of an end device from a data packet received from an end device. A DHCPv6 data frame is created for transmission to a DHCPv6 server. The MAC address may be inserted into a specific option of the DHCPv6 data frame, where data in the option may not be processed by the server and are echoed back to the aggregation component or CMTS. The DHCPv6 data frame is transmitted to the DHCPv6 server. The component receives a response message from the server that may contain the MAC address or similar client hardware address as it was sent to the server by the network component. The network component may determine an outgoing port interface from which the response message should be sent, utilizing the MAC address and an interface bundling table. In this manner, interface bundling may be enabled.

Stateful DHCPv6 relay agent in a cable modem termination system

A network device has a communications link to allow the device to communicate with customer devices and a processor. The processor is to receive neighbor discovery messages from requesting customer devices, examine the neighbor discovery messages to determine if the neighbor discovery message should be forwarded to other of the customer devices, and respond to the requesting customer devices.

Neighbor discovery in cable networks

A network device is to receive traffic including neighbor discovery messages from requesting customer devices, and can detect the neighbor discovery messages within the traffic according to a distributed inspection scheme that includes the network device and a remote component. The network device is to then examine the neighbor discovery messages to determine if the neighbor discovery message should be forwarded to other of the customer devices, and respond to the requesting customer devices.

Neighbor discovery proxy with distributed packet inspection scheme

An embodiment method may comprise establishing a link layer connection to an access server, obtaining a management address, wherein the management address is at least one of an IPv6 and an IPv4 address, obtaining a TFTP server address, wherein the server address is either IPv6 or IPv4, downloading a configuration file from the TFTP server, registering with the access server as IPv6 capable, maintaining an IP address/prefix-MAC mapping database, and determining whether the IPv6 address belongs to a particular media access control (MAC) address based on the IP address/prefix-MAC mapping database.

A management scheme compares a source address included in a received solicitation with an address for a registered endpoint. A communication including a management prefix is communicated to the endpoint when the source address matches the registered address.

Growing community of inventors

San Jose, CA, United States of America

Madhu Sudan