Ramanathan Venkateswaran

US Patent:

58319751, Nov 3, 1998

Filed:

Apr 4, 1996

Appl. No.:

8/627637

Inventors:

Xiaoqiang Chen - Eatontown NJ
Vijay Pochampalli Kumar - Freehold NJ
Ramanathan Venkateswaran - Pullman WA

Assignee:

Lucent Technologies Inc. - Murray Hill NJ

International Classification:

H04L 1256

US Classification:

370256

Abstract:

The present invention extends the PNNI protocols to support hierarchical multicast routing and signaling for ATM networks. The invention utilizes an extension to a core-based tree algorithm. Instead of a single core node, core nodes are maintained in each peer-group and at each level of the hierarchy. The advantage of this is that one single core node is not overloaded. Additionally, this increases fault-tolerance because there are no single points of failure. As would be understood, the present invention is highly scaleable because of the hierarchical nature of PNNI. In addition, the scheme supports multiple senders and dynamic membership changes to the multicast group. Quality of service requirements can be negotiated during connection setup and are guaranteed during the course of the connection. Though some additional topological information has to be flooded in the peer-groups to compute efficient multicast routes, the overheads to the connection management are minimal. The multicast tree is built incrementally and the cost of the tree is comparable to the cost of the Steiner Tree computed using some standard heuristics.

US Patent:

59463163, Aug 31, 1999

Filed:

Jan 17, 1997

Appl. No.:

8/785625

Inventors:

Xiaoqiang Chen - Eatontown NJ
Vijay Pochampalli Kumar - Freehold NJ
Ramanathan Venkateswaran - Holmdel NJ

Assignee:

Lucent Technologies, Inc. - Murray Hill NJ

International Classification:

H04L 1256

US Classification:

370408

Abstract:

The distribution of multicast information in a communications network formed from a plurality of communications nodes, e. g. , ATM switches, is enhanced by providing an efficient mechanism for routing a request to join a multicast connection to an originator of the multicast and an efficient mechanism for then connecting the requester to the multicast connection.

US Patent:

61446661, Nov 7, 2000

Filed:

Oct 20, 1997

Appl. No.:

8/954759

Inventors:

Xiaoqiang Chen - Eatontown NJ
Vijay Pochampalli Kumar - Freehold NJ
Ramanathan Venkateswaran - Chicago IL

Assignee:

Lucent Technologies Inc. - Murray Hill NJ

International Classification:

H04L 1250

US Classification:

370395

Abstract:

In an asynchronous transfer mode (ATM) communications system, all ATM switches in a multicast connection perform virtual path (VP) switching except those merge points which perform virtual channel (VC) switching to avoid VCI collisions. The merge points are ATM switches which can merge ATM traffic from at least two incoming links into an outgoing link. In a second approach, each merge point in a multicast connection performs VP switching, and dynamically dispenses VC switching when a VCI collision is detected. Specifically, to prevent further VCI collision, incoming ATM cells indicated by an odd VPI value are VC switched by the merge point while those indicated by an even VPI value are VP switched thereby.