Nortel Networks Corporation

Northern Telecom Limited

James Alexander Shields

David Michael Goodman

Christopher David Murton

John Paul Russell

Roy Harold Mauger

Julian Frank Barry Cable

Mark Ashworth

Christopher Ramsden

Christopher Thomas William Ramsden

Patrick D Bradd

Bram Peeters

Bryan J Miller

Friskney Robert

A communications network arrangement provides voice over IP or voice over ATM services. The network arrangement comprises a first media gateway controller controlling a first gateway and provided with a first operating protocol, a second media gateway controller controlling a second gateway and provided with a second operating protocol, and a gateway address translator incorporating proxies for the first and second gateways. The gateway address translator provides a relay function for messaging between each media gateway controller and its corresponding gateway, and a virtual bearer function for messaging between the media gateway controllers. This facilitates inter-working between products supplied by different vendors.

Voice over packet network arrangement and method

A method of transmitting OSI layerdatacoms data by direct incorporation into a plurality of synchronous digital hierarchy virtual containers is disclosed, in which a higher bit rate OSI layerdata frame is multiplexed into a plurality of lower bit rate SDH (or SONET) virtual containers, which are transmitted simultaneously and in parallel over a synchronous communications network. The plurality of virtual containers are virtually concatenated by association of the payloads of the plurality of virtual containers. Re-assembly of the OSI layerdata frames from a plurality of virtually concatenated VCs is achieved by storing each received VC payload corresponding to an OSI layerdata frame in a corresponding respective memory location, and alternately reading interleaved bytes from the plurality of payloads under control of a plurality of read pointers.

Concatenation of containers in synchronous digital hierarchy network

Narrowband subscriber terminals () of different narrowband networks are interconnected via a broadband network () that supports dissimilar signaling protocols to those maintained on the respective narrowband networks (). A call server in a first narrowband network (), in response to a call () from a first subscriber terminal () to a second subscriber terminal () in a second but different narrowband network (), selects a phantom trunk () between the two networks. The phantom trunk has a unique circuit identity, which circuit identify is used in a first instance to relay to the second network an address of the second subscriber terminal (). Then, in a second instance, the unique circuit identify is used to relay to the second network an address of the first subscriber terminal (). By recognizing that two connection requests have been received at opposite ends of the same phantom trunk, a processor in the second network is able to determine that a direct connection between the first and second subscriber terminals is required through the broadband network ().

System and method for establishing a communication connection

A method of and system for determining a path through which to route a connection in a photonic network in which optically viable photonic paths of one or more physical links are determined and considered as 'virtual' links in a 'virtual' topology. Routing is then performed using the &#x201c;virtual&#x201d; topology rather than the physical topology to compute &#x201c;virtual&#x201d; paths of one or more &#x201c;virtual&#x201d; links.

Method of and system for routing in a photonic network

There is disclosed a method of carrying frame based data, eg Ethernet data, over a synchronous digital hierarchy network in order to provide local area network type functionality over a wide area network coverage. Specific embodiments disclose methods of mapping Ethernet data frames into SDH virtual containers, and distinguishing start and end boundaries of the Ethernet data frames within the virtual container payloads, by a selection of encoding methods including a segmentation, pointer methods, bit stuffing methods and byte stuffing methods. Data frames are encoded with a code which designates a boundary of each frame, and the encoded frames are input into a synchronous data channel.

Payload mapping in synchronous networks

Narrowband subscriber terminals ( ) of different narrowband networks are interconnected via a broadband network ( ) that supports dissimilar signalling protocols to those maintained on the respective narrowband networks ( ). A call server in a first narrowband network ( ), in response to a call ( ) from a first subscriber terminal ( ) to a second subscriber terminal ( ) in a second but different narrowband network ( ), selects a phantom trunk ( ) between the two networks. The phantom trunk has a unique circuit identity, which circuit identify is used in a first instance to relay to the second network an address of the second subscriber terminal ( ). Then, in a second instance, the unique circuit identify is used to relay to the second network an address of the first subscriber terminal ( ). By recognizing that two connection requests have been received at opposite ends of the same phantom trunk, a processor in the second network is able to determine that a direct connection between the first and second subscriber terminals is required through the broadband network ( ).

Broadcast video desynchronizer

The leak rate of the primary buffer in a desynchroniser buffer at the exit from a synchronous transport network to a plesiochronous tributary is controlled in a manner such that the absolute rate of change of leak rate is maintained substantially constant during the periods in which the leak rate is increased or decreased.

Desynchronising video information from synchronous network to a

Optical clock recovery is performed on an optical signal containing both data and clock information by applying it to a photodetector and adding part of the resulting electrical signal to the bias of a self-pulsating laser diode so as to force its pulsation frequency to the frequency and phase of the clock component of the optical signal.

Growing community of inventors

Carrickfergus, United Kingdom

James Alexander Shields