Steven J Sherry

US Patent:

6466577, Oct 15, 2002

Filed:

Apr 12, 1999

Appl. No.:

09/290051

Inventors:

Pierre A. Humblet - Cambridge MA
Bruce D. Miller - North Reading MA
Raj Shanmugaraj - Groton MA
Steven Sherry - Needham MA

Assignee:

Alcatel Communications, Inc. - Chelmsford MA

International Classification:

H04L 1228

US Classification:

3703953, 370397, 370409

Abstract:

A mechanism for providing point-to-point and point-to-multipoint connections in an ATM network converts VPI/VCI information at an ingress ATM device on incoming cells from a source endpoint to internal VP/VCI information that is used to switch the cells through an ATM network to an egress ATM device. At the egress ATM device, the internal VPI/VCI information is converted back to the source VPI/VCI information for transmission of cells to the destination endpoint. In such a manner, an ATM switch network is able to provide point-to-point connections without requiring individual configuration of VPI/VCI information at the ingress and egress ATM devices.

US Patent:

6992978, Jan 31, 2006

Filed:

Jun 2, 1999

Appl. No.:

09/324454

Inventors:

Pierre A. Humblet - Cambridge MA, US
Bruce D. Miller - North Reading MA, US
Raj Shanmugaraj - Groton MA, US
Steven Sherry - Needham MA, US
Peter B. Beaulieu - Plaistow NH, US
Michael W. Fortuna - Fremont NH, US
Michael C. Yip - Wellesley MA, US
William Abraham - Windham NH, US

Assignee:

Alcatel Communications, Inc. - Plano TX

International Classification:

H04J 11/06
H04J 3/14

US Classification:

370228, 370227

Abstract:

A system and method for fast and reliable failure notification and accelerated switchover for path protection in a communications network having several overlapping areas of nodes interconnected by communications links is described. Upon a failure event involving one of the communications links, a failure message is broadcast identifying the failed link, the broadcast being confined within the areas which include the failed link. A reliable transmission protocol is provided wherein at one or more of the nodes, a LAPD protocol unnumbered information frame containing the failure message is sent to connected nodes. The failure message is resent in another unnumbered information frame after a time interval unless an unnumbered acknowledgment frame containing or referencing the failure message is received from the connected node. A method of path protection includes establishing plural working paths through the nodes. For each working path, an associated protection path is precalculated.

US Patent:

53155920, May 24, 1994

Filed:

Apr 23, 1992

Appl. No.:

7/872516

Inventors:

George E. Conant - Acton MA
Steven H. Sherry - Lynnfield MA
Scott G. Wasson - Shrewsbury MA

Assignee:

Xyplex Inc. - Boxborough MA

International Classification:

H04J 302

US Classification:

370 8513

Abstract:

A network with parallel bridges transmits information packets over parallel paths between first and second terminals in a network having other terminals while maintaining conformity with a protocol that precludes establishing loops formed by links between terminals that allow information packets to recirculate indefinitely. There is a first pair of bridges with each bridge connected to a respective one of the first and second terminals and interconnected by a first link. There is a second pair of bridges each connected to a respective one of the first and second terminals and interconnected by a second link. At least one bridge in each of the first pair of bridges and the second pair of bridges is designatable as a master bridge and has a forwarding/filtering module for forwarding and filtering information packet transfer between the first and second terminals, a topology recognition/traffic assignment module for sensing the existence of parallel transmission paths between the first and second terminals and assigning information packets to respective ones of the parallel transmission paths for transfer between the first and second terminals, and a spanning tree module for providing a spanning tree bridge identifier signal. A spanning tree bridge identifier signal sensor senses the spanning tree bridge identifier signals and designates as a master that bridge having the spanning tree bridge identifier signal meeting a pre-determined condition.