At+t Corp.

Lucent Technologies Inc.

At&t Ipm Corp.

Behram H Bharucha

Arik Kashper

Steven S Katz

Thomas S Giuffrida

Norman Farber

Thomas P Chu

Sanjiv Nanda

Subrahmanyam Dravida

Bharat Tarachand Doshi

Seyhan Civanlar

James Frederick Bradley

Charles W Gritton

John H Baldwin

Dario L Parola

Richard Zoccolillo

This proposal outlines an approach for interfacing Synchronous Transfer Mode (STM) and Asynchronous Transfer Mode (ATM) networks and for transporting voice, fax and voice-band data calls by the ATM network in an efficient manner. In contrast to the well known ATM Variable Bit Rate (VBR) approach, this proposal allows one to transport 64 kb/s traffic efficiently over ATM by re-using STM network signaling and exploiting the standard AAL-1-type adaptation layer (intended for Constant Bite Rate, CBR, services). We use low bit rate encoding algorithms and achieve additional compression for speech by marking cells that do not contain talk spurts. The invention defines specific rules for STM-to-ATM interfacing, including all routing translation, and identifies necessary Terminal Adapter (TA) and ATM switch capabilities. This approach is an advancement over previous inventions that specified network architecture and terminal adapter requirements to provide a graceful transition from an STM network (for example the AT&T long distance network) to an ATM network. Prior art described how to emulate an STM network in the ATM domain, but did not permit for compression and silence elimination and, therefore, did not allow achieving efficiency gains.

Voice-over-ATM switch architecture allowing congestion-dependent transport of silence cells

Telecommunications network architecture for transporting fax, voice and data via an ATM switch including a STM to ATM terminal adapter

A system transmits compressed voice packets over ATM. The system receives a plurality of voice data units and an encoding rule for each voice data unit. A packet is formed from the received data units. The packet includes a header. The header includes the amount of data units in the packet, and the encoding rule for each packet. The packet is then placed in an ATM cell which is transmitted on an ATM virtual channel. The ATM cell includes at most one packet.

Method and apparatus for transmitting compressed packetized voice over ATM

AAL,mini packets are integrated directly onto the physical layer to provide serial data transmission using statistical multiplexing. This can be achieved by generating a plurality of frames of a predetermined size. A plurality of AAL,variable length mini packets are then statistically multiplexed onto the plurality of frames. A pointer field is then inserted into each of the frames. The pointer field includes a pointer that delineates the starting place of the next full packet in the frame that includes the pointer field, a framing bit that forms a pattern with other framing bits, and a parity bit. The frames are then transmitted over a serial transmission line.

Serial data transmission of variable length mini packets using statistical multiplexing

A telecommunication network establishes a telephone call from a first location that generates compressed voice packets to a second location. The telecommunication network includes a plurality of switches, a first interworking function ('IWF') coupled to the first location and coupled to a first switch of the plurality of switches, a second IWF coupled to the second location and coupled to a second switch of the plurality of switches, and a network database coupled to said first switch. When a telephone call is initiated from the first location, the first switch receives signaling information from the first location. The first switch then queries the network database based on the signaling information and determines whether the second location uses compressed voice packets based on the query. Finally, the first switch establishes a connection between the first IWF and the second IWF if it is determined that the second location uses compressed voice packets. The connection bypasses the plurality of switches, and therefore reduces tandeming in the network.

Telecommunication network that reduces tandeming of compressed voice

A method and apparatus for transmitting and/or receiving variable-length packets (e.g., CDMA packets, CDPD packets) that are associated with different channels and which are multiplexed via a single virtual circuit (e.g., an ATM virtual circuit).

Multi-channel broadband adaptation processing

An ATM cell carrying a voice-band signal originating in an STM network is processed in accordance with a particular signal processing function in an ATM mode at an ATM data rate without incurring a delay penalty that arises.

Delay-less signal processing arrangement for use in an ATM network

Growing community of inventors

Millburn, NJ, United States of America

Behram H Bharucha