Yakov Y Rekhter

6339595, Jan 15, 2002

Dec 23, 1997

08/997343

Yakov Rekhter - New Rochelle NY
Eric C. Rosen - Arlington MA

Cisco Technology, Inc.

H04L 1228

370392, 370400, 370401

A service providers routers (PE P , P PE ) provide connections between and share routine information with routers (CE CE ) of a customer virtual private network (VPN) as well as routers of other customers VPNs, which may have overlapping address spaces. A service providers edge router (PE ) informed by the customers router (CE ) that it will forward packets to a given prefix notifies the other edge router (PE ) that PE can forward packets to that address prefix if the destination is in the VPN to which CE belongs. PE also tells PE to tag any thus-destined packets with a particular tag T PE stores this information in a forwarding information base that it separately keeps for that VPN so that when PE receives from a router CE in the same VPN a packet whose destination address has that prefix, it tags the packet as requested. But PE also tags it with a tag T that the router P to which PE first sends it has asked PE to apply to packets to be sent to PE P routes the packet in accordance with T sending it to P after replacing T with a tag T that P has similarly asked P to use. P removes T from the packet and forwards it in accordance with T to PE which in turn removes T from the packet and forwards it in accordance with T to CE In this manner, only the edge routers need to maintain separate routing information for separate VPNs.

6463061, Oct 8, 2002

Jan 19, 1999

09/232947

Yakov Rekhter - New Rochelle NY
Eric C. Rosen - Arlington MA

Cisco Technology, Inc. - San Jose CA

H04L 1228

370392, 370401

A service providers routers (PE P P PE ) provide connections between and share routing information with routers (CE CE ) of a customer virtual private network (VPN) as well as routers of other customers VPNs, which may have overlapping address spaces. A service providers edge router (PE ) informed by the customers router (CE ) that it will forward packets to a given prefix notifies the other edge router (PE ) that PE can forward packets to that address prefix if the destination is in the VPN to which CE belongs. PE also tells PE to tag any thus-destined packets with a particular tag T PE stores this information in a forwarding information base that it separately keeps for that VPN so that when PE receives from a router CE in the same VPN a packet whose destination address has that prefix, it tags the packet as requested. But PE also tags it with a tag T that the router P to which PE first sends it has asked PE to apply to packets to be sent to PE P routes the packet in accordance with T sending it to P after replacing T with a tag T that P has similarly asked P to use. P removes T from the packet and forwards it in accordance with T to PE which in turn removes T from the packet and forwards it in accordance with T to CE In this manner, only the edge routers need to maintain separate routing information for separate VPNs.

6526056, Feb 25, 2003

Dec 21, 1998

09/217976

Yakov Rekhter - New Rochelle NY
Eric C. Rosen - Arlington MA

Cisco Technology, Inc. - San Jose CA

H04L 1228

370392, 370400, 370474

A service providers routers (PE P P PE ) provide connections between and share routing information with routers (CE CE ) of a customer virtual private network (VPN) as well as routers of other customers VPNs, which may have overlapping address spaces. A service providers edge router (PE ) informed by the customers router (CE ) that it will forward packets to a given prefix notifies the other edge router (PE ) that PE can forward packets to that address prefix if the destination is in the VPN to which CE belongs. PE also tells PE to tag any thus-destined packets with a particular tag T PE stores this information in a forwarding information base that it separately keeps for that VPN so that when PE receives from a router CE in the same VPN a packet whose destination address has that prefix, it tags the packet as requested. But PE also tags it with a tag T that the router P to which PE first sends it has asked PE to apply to packets to be sent to PE P routes the packet in accordance with T sending it to P after replacing T with a tag T that P has similarly asked P to use. P removes T from the packet and forwards it in accordance with T to PE which in turn removes T from the packet and forwards it in accordance with T to CE In this manner, only the edge routers need to maintain separate routing information for separate VPNs.

6597663, Jul 22, 2003

Jul 26, 1999

09/360711

Yakov Rekhter - Putnam Valley NY

Cisco Technology, Inc. - San Jose CA

H04J 116

370252, 370238, 370389, 709238

A detection technique detects inconsistencies in forwarding databases of a router and its neighbor, i. e. , a next-hop router, during routing transients in a computer network. The technique enables the router to detect when its view of a computed path to a destination station is inconsistent with the view of its neighbor along that path. Upon detecting such an inconsistent state, the router invokes one of a plurality of forwarding mechanisms with respect to a packet intended for the destination station in an attempt to suppress forwarding loops that may arise during the transients.

6611528, Aug 26, 2003

Oct 10, 2000

09/685219

Dino Farinacci - San Jose CA
Yakov Rekhter - New Rochelle NY

Cisco Technology, Inc. - San Jose CA

H04L 400

370432, 370390, 370400

The invention provides a method and system for multicast packet routing, in which only selected routers in a network subset (in a preferred embodiment, those routers on the border of the domain) maintain routing information external to the network subset, while all other routers in the network subset (non-border routers) maintain only information regarding routing within the network subset, including which border routers are on the path from the multicast source device or to the destination devices. The network subset is preferably a domain or other routing domain. A multicast distribution tree is maintained, using protocol messages which are transmitted from leaf nodes toward a root of the tree, while data packets to be multicast are distributed from the root toward the leaf nodes. In each network subset, such as a routing domain, each multicast packet is associated with a multicast distribution tree. The multicast distribution tree is associated with an upstream border router (UBR) and a set of downstream border routers (DBRs).

6697360, Feb 24, 2004

Sep 2, 1998

09/145600

Silvano Gai - Vigliano dAsti, IT
Keith McCloghrie - San Jose CA
Yakov Rekhter - New Rochelle NY

Cisco Technology, Inc. - San Jose CA

H04L 1256

370389, 370401, 370475, 709220

A method and apparatus for auto-configuring layer intermediate devices in computer networks by extending the Dynamic Host Configuration Protocol (DHCP). The devices generate, transmit and receive DHCP messages having novel options embedded therein. The options permit a layer device to request and receive from a DHCP server a unique, overall IP address that may be assigned to the device. The device may also request and receive one or more IP subnets and corresponding IP addresses for each of its interfaces. The device may further receive the routing protocols to be used on the various subnets. The layer device can thus be auto-configured with IP configuration parameters, including IP subnets, IP addresses and routing protocols without the time-consuming, manual involvement of a network administrator.

6704795, Mar 9, 2004

Oct 12, 1999

09/416461

Rex Emmanuel Fernando - San Jose CA
Yakov Rekhter - New Rochelle NY

Cisco Technology, Inc. - San Jose CA

G06F 1516

709237, 709238, 709242

A technique reduces consumption of resources on behalf of a router and its neighboring routers by deferring the point at which the router renders a route selection decision in accordance with a Border Gateway Protocol (BGP). A BGP KEEPALIVE message is selectively issued to enable the router to detect that each of its neighbors has finished sending all of its routes. After detecting that it has received a full set of routes from each neighbor, the router performs route selection procedures to select the preferred routes and advertises these routes to its neighbors.

7154889, Dec 26, 2006

Oct 23, 2001

10/001516

Yakov Rekhter - New Rochelle NY, US
Eric C. Rosen - Arlington MA, US

Cisco Technology, Inc. - San Jose CA

H04L 12/28

370392, 370400, 370401

A service provider's routers (PE, P, P, PE) provide connections between and share routing information with routers (CE, CE) of a customer virtual private network (VPN) as well as routers of other customers' VPNs, which may have overlapping address spaces. A service provider's edge router (PE) informed by the customer's router (CE) that it will forward packets to a given prefix notifies the other edge router (PE) that PE can forward packets to that address prefix if the destination is in the VPN to which CE belongs. PE also tells PE to tag any thus-destined packets with a particular tag T. PE stores this information in a forwarding information base that it separately keeps for that VPN so that when PE receives from a router CE in the same VPN a packet whose destination address has that prefix, it tags the packet as requested. But PE also tags it with a tag T that the router P to which PE first sends it has asked PE to apply to packets to be sent to PE. P routes the packet in accordance with T, sending it to P after replacing T with a tag T that P has similarly asked P to use.