Cisco Technology, Inc.

Chickayya Naik

Giovanni Meo

Dileep Kumar Devireddy

Marco Foschiano

Vijayan Ramakrishnan

Cheng Tang

Ashoka Kallappa

Senthilkumar Krishnamurthy

Raja Kommula

Toerless Eckert

Mouli Vytla

David Walker

Yiqun Cai

Jonathan Davar

Kevin C Wong

Francesco Meo

Gaetano Borgione

Karthikeyan Gurusamy

Jason Allen Marinshaw

Mukul Chawla

Sharanya Subramanian

Naren Mididaddi

A network device includes a control processor and a network processor unit (NPU) to forward network packets between network ports of the device. The processor downloads a new operating system (OS). The processor performs a fast upgrade to the new OS using a fast upgrade/reload technique to isolate the processor from interruptions and, without rebooting the processor, start the new OS in place of an existing OS. The fast upgrade/reload also includes delaying a reset of the NPU so that the NPU continues to route the network packets based on existing forwarding information. The fast upgrade/reload includes resetting the NPU only when the new OS first accesses the NPU, and then programming the reset NPU.

Technique for fast network device configuration upgrade and reload

An apparatus and related method are provided for improving the performance of virtual desktop services. A network device is deployed in a network to intercept packets of a control session initiated by a client with a connection broker to obtain data from a host. The network device initiates a new control session to the connection broker on behalf of the client. The network device receives host information from the connection broker, replaces address information of the network device for the host information in a control session message and sends the control session message to the client. The network device establishes a data session with the client, initiates a data session with the host on behalf of the client and relays data between the data session with the host and the data session with the client such that the network device is transparent to the client and the host.

Display protocol interception in the network for services and network-based multimedia support for VDI

A Multicast Listener Discovery (MLD) protocol query and/or report snooping process is modified to appropriately map secondary PVLAN identifiers to corresponding primary PVLAN identifiers, thereby accommodating other system elements that are otherwise unaware of primary/secondary PVLAN distinctions. Special cases are also accommodated where reverse path forwarding (RPF) checks in support of multicast operation might otherwise fail due to primary/secondary PVLAN distinctions. Additional steps are taken to ensure that PVLAN information properly accounts for changes in configuration and/or location of various network hosts.

Systems and methods for multicast switching in a private VLAN

A method, system, and apparatus to transmit replicated multicast packets over a plurality of physical network links that are combined into one logical channel or link so that the replicated multicast packets are distributed over more than one network link is disclosed. It is further disclosed that distribution over the network links is accomplished, in part, through analyzing the multicast packet for information other than ethernet addresses. Such information can include a tag header including destination interface information.

Apparatus and method for utilizing aggregate network links for multicast switching

Cascading a lookup over multiple lookup tables when performing multicast forwarding involves accessing a first lookup table based on at least part of a multicast destination address included in a packet header. The first lookup table identifies the portion (e.g., one or more entries) of a second lookup table in response to a key generated from a first portion of the packet header. The portion of the second lookup table can be accessed based on a second portion of the packet header. The second lookup table identifies at least one output interface via which the packet should be output. Such systems and methods may, in some embodiments, allow existing hardware to be used to support a new addressing format that involves larger addresses than were previously supported by that hardware.

System and method for performing cascaded lookups to forward packets

Efficient multicasting within a layer 2 network is provided. Participation by a layer 3 router is not required. The spanning tree created by common layer 2 networking protocols is exploited for multicast signaling and traffic handling.

Efficient multicast packet handling in a layer 2 network

A method and system for controlling admission of an end user to a multicast channel over a network implementing a source filtering protocol. Incoming packet traffic received by an edge router is snooped and, when a request to join a multicast channel is received, the traffic is analyzed. Any service policy associated with the traffic class is found and applied to packet traffic from the requesting user. The actions include accepting membership in a group associated with a multicast channel and pushing the packets to the end user. If the action is to deny membership, then the multicast packets are prevented from reaching the end user. In addition information is logged and may be used for billing purposes or for accumulating marketing or other such information. Also, the actions may be to limit the number of routing states, by denying admittance to a groups once a limit number of requests to join, or other such parameter, is reached. Such limiting will substantially prevent DOS attacks on a multicast router.

Admission control mechanism for multicast receivers

The invention relates to a system and method for efficiently distributing multicast messages within computer networks configured to have one or more virtual local area network (VLAN) domains. A multicast network device (MND), having a plurality of interfaces, includes a multicast controller for efficiently distributing multicast messages among subscribing entities associated with various VLAN domains. The multicast controller, which is in communicating relationship with the interfaces, includes a VLAN assignment engine for assigning responsibility for the VLAN domains to the extent there are multiple MNDs. The multicast controller also accesses a multicast tag source to establish a plurality of novel VLAN tags for efficiently distributing multicast messages, including a sub-regional Multicast VLAN Identifier (MVLAN-ID) that encompasses all of the VLAN domains for which the respective MND is responsible, and one or more color-limited MVLAN-IDs that encompass all of the VLAN domains for which the MND is responsible except for one. The multicast controller then tags multicast messages with its sub-regional or a color-limited MVLAN-ID depending on whether the message is considered internal or external by the respective MND. The tagged messages are then forwarded for distribution to the subscribers associated with the various VLAN domains.

System and method for distributing multicasts in virtual local area networks

A technique implements forwarding operation shortcuts at a switch for multicast data traffic routed between subnetworks of a computer network. A first multicast frame is forwarded from the switch to a router, which peforms route processing and forwarding operations for a packet encapsulated within the frame. During execution of the operations, the router provides multicast flow and additional information concerning the routed packet to the switch in accordance with a novel multicast shortcut control protocol. The information is used by the switch to implement a novel multicast shortcut for subsequent frames received at the switch having the multicast packet flow.

Growing community of inventors

San Jose, CA, United States of America

Chickayya Naik