Xuewen E Li

US Patent:

6636508, Oct 21, 2003

Filed:

Feb 12, 1999

Appl. No.:

09/249696

Inventors:

Xuewen Li - Cary NC

Assignee:

Nortel Networks Limted - St. Laurent

International Classification:

H04L 1228

US Classification:

370389, 370402, 370352

Abstract:

A communications network resource conservation system is provided for that conserves network bandwidth and improves voice quality. The method and apparatus permit users of H. 323 terminal devices to talk to each other directly over the Internet thereby eliminating the need to use the resources of a telephone switch and a Public Switched Telephone Network (PSTN). Communication between users is established directly via packet network. In one embodiment, a voice path between users is directly established without routing the voice through a PSTN as for a typical telephone call and yet get supplementary services from the PSTN switch. The telephone call will be set up through the telephone switch and the PSTN as for a normal call, but, the voice path will be Intraswitched directly between the calling party and the called party via their packet network. In another embodiment, the invention provides a way to revert an Intraswitched call through the telephone switch automatically when needed to invoke supplemental features of telephony service.

US Patent:

6775277, Aug 10, 2004

Filed:

Feb 18, 2000

Appl. No.:

09/507277

Inventors:

Xuewen Li - Cary NC
Allan Jeffrey Hinchey - Kanata, CA
David P. Ress - Cary NC

Assignee:

Nortel Networks Limited - St. Laurent

International Classification:

H04L 1256

US Classification:

370389, 370401, 370475, 709223

Abstract:

A method for processing calls in a packet network using peer call servers includes receiving a setup message from a first gateway in the packet network. The setup message includes a first address for a called endpoint. The call server that receives the setup message translates the message into a call server ID and an endpoint ID specifying the remote call server corresponding to the called party. The call server sends the call server ID and the endpoint ID to the remote call server. The remote call server obtains a call signaling transport address to the called end user based in the endpoint ID.

US Patent:

6798786, Sep 28, 2004

Filed:

Aug 20, 1999

Appl. No.:

09/370984

Inventors:

Wing F. Lo - Plano TX
Xuewen Li - Cary NC
Alireza Abaye - Plano TX

Assignee:

Nortel Networks Limited - St. Laurent

International Classification:

H04Q 700

US Classification:

370468, 370329, 370392, 370352, 709226

Abstract:

A method and system of managing calls over a data network includes determining an available bandwidth of the data network. After a call request is received for establishing a call between at least two network terminals, one or more of a plurality of resource elements are selected in response to the call request based on the bandwidth of the data network. The resource elements, which can include codecs (coders/decoders), packet sizes (for carrying audio data), and others, are used in the requested call between the at least two network terminals. Further, a plurality of communities may be defined each including one or more terminals. One or more usage threshold values may be assigned to a link or links between communities, and a call request is processed based on the one or more usage threshold values. The processing includes at least one of determining whether to admit the call request and selecting resource elements to be used during a call between terminals over the link.

US Patent:

6885658, Apr 26, 2005

Filed:

Feb 18, 2000

Appl. No.:

09/506945

Inventors:

David P. Ress - Cary NC, US
Xuewen Li - Cary NC, US
Denise J. Ingram - Morrisville NC, US
Gregory Robert Utas - Irving TX, US

Assignee:

Nortel Networks Limited - St. Laurent

International Classification:

H04L012/66
H04J003/22

US Classification:

370352, 370401, 370466

Abstract:

A method and an apparatus for interworking between internet protocol (IP) telephony protocols includes a call server. The call server includes a first protocol agent for communicating with a first protocol device according to a first protocol. A second protocol agent communicates with a second protocol device according to a second protocol. An interworking agent provides functions usable by the first and second protocol agents to communicate with each other according to a third protocol. The third protocol is a superset of functions provided by the first and second protocols.

US Patent:

6907462, Jun 14, 2005

Filed:

Jun 4, 2003

Appl. No.:

10/454208

Inventors:

Xuewen Li - Cary NC, US

Assignee:

Nortel Networks Limited - St. Laurent

International Classification:

G06F013/00

US Classification:

709226, 709229, 709249, 719311, 370401

Abstract:

Methods and systems for controlling network gatekeeper message processing include overload control routines executed by a network gatekeeper to prevent the network gatekeeper from crashing during overload conditions. The overload control routines are executed in a predetermined order so that messages relating to calls in progress are preferentially processed over messages relating to newly originating calls. Fault detection routines detect protocol stack and application level faults of a network gatekeeper.

US Patent:

6961332, Nov 1, 2005

Filed:

Apr 25, 2001

Appl. No.:

09/842298

Inventors:

Xuewen Li - Cary NC, US
Carroll L. Gray-Preston - Morrisville NC, US
Junhui Ma - Cary NC, US

Assignee:

Nortel Networks Limited - St. Laurent

International Classification:

H04L012/66

US Classification:

370352, 370401

Abstract:

The present invention provides for a multiple appearance directory number (MADN) group including terminals on both the public switched telephone network (PSTN) and a packet-switched network. The terminals within the MADN group are preferably on the PSTN and a packet-switched network under the control of the PSTN. While call signaling is centralized and provided by the PSTN, a full complement of PSTN services are available to the terminals on the packet-switched network. With centralized call control and access to services from the PSTN, IP terminals on the packet-switched network are treated as if they were PSTN terminals by PSTN elements, and are capable of implementing PSTN features and functions.

US Patent:

7801157, Sep 21, 2010

Filed:

May 25, 2004

Appl. No.:

10/852890

Inventors:

Xuewen Li - Cary NC, US
Allan Jeffrey Hinchey - Kanata, CA
David P. Ress - Cary NC, US

Assignee:

Nortel Networks Limited - St. Laurent, Quebec

International Classification:

H04L 12/56

US Classification:

370401, 370352, 370389

Abstract:

A method for processing calls in a packet network using peer call servers includes receiving a setup message from a first gateway in the packet network. The setup message includes a first address for a called endpoint. The call server that receives the setup message translates the message into a call server ID and an endpoint ID specifying the remote call server corresponding to the called party. The call server sends the call server ID and the endpoint ID to the remote call server. The remote call server obtains a call signaling transport address to the called end user based in the endpoint ID.

US Patent:

7995561, Aug 9, 2011

Filed:

Dec 7, 2006

Appl. No.:

11/608061

Inventors:

Xuewen Li - Cary NC, US
Xiaohong Wang - Cary NC, US
Jujar Nagdi - Cary NC, US

Assignee:

Nortel Networks Limited - St. Laurent, Quebec

International Classification:

H04L 12/66

US Classification:

370352, 370392, 370522

Abstract:

Techniques for implementing logical trunk groups with session initiation protocol (SIP) are disclosed. In one particular exemplary embodiment, the techniques may be realized as an apparatus for implementing logical trunk groups with session initiation protocol (SIP). The apparatus may comprise a first network device and a second network device that are configured to exchange SIP signaling messages. Network traffic between the first network device and the second network device may be segregated into one or more logical groups. The SIP signaling messages associated with each logical group may include a Route header that uniquely identifies the logical group between the first network device and the second network device.