International Telephone and Telegraph Corporation

Alcatel Network Systems, Inc.

Stephen C Dunning

Joseph E Sutherland

Michael J Gingell

Claude M Hurlocker

Raymond E Tyrrell

Richard J Sanders, Jr

Jeffrey P Jones

Richard Marion Czerwiec

William B Weeber

William E Powell

Timothy J Williams

Joseph Lee Smith

Ertugrul Baydar

Dale L Krisher

William J Fox

Richard W Peters

William H Stephenson, Jr

Gus C Sanders, Jr

Hal A Thorne

Francis G Noser

Jak Yaemsiri

Keith L Bernhardt

Camille A Abu-Saba

Michael Sutton

James T Gwathmey

O Lamar Bishop

M Rodney Briscoe

Kenneth J Stoia

V Paul Runyon

Heinrich T Sonnenberg

Patrick M Farrell

Victor W Wilkerson

Mohammad S Arani

Dana Merrill

Wenkwei Rou

A synchronous optical transmission system for interfacing SONET formatted channels to lower speed channels in either a SONET format or otherwise. The transmission system incorporates a fiber transmission system, terminal multiplexers and add/drop multiplexers that in turn incorporate a plurality of features, such as parallel scrambling circuitry, frame synchronization circuitry and the like.

Synchronous optical transmission system

A serial transport frame format is described which transfers data between two locations. The serial transport frame format comprises a fixed number of channels per frame, each channel having a predetermined size. One channel per frame contains frame synchronization information and each channel which conveys data, contains a first portion for the transfer of data and a second portion which contains associated control information.

Serial transport frame format method

A telephone switching network is disclosed, which network is adapted to provide connections between a plurality of input subscriber lines. The network includes a time slot interchanger which comprises a transmit switch memory and a receive switch memory. The transmit and receive memories are capable of storing data at addressable storage locations, which data is indicative of digital data to be transmitted from a line circuit and digital data to be received by a line circuit during a connection between the two line circuits. A connect memory is also employed for storing data indicative of connections to be made between line circuits. The connect memory as well as the switch memories are controlled in operation by a processor, which processor includes an access control means. The processor and the access control means are operative to cause the connect memory to couple corresponding storage locations of the transmit and receive memories indicative of one subscriber line to corresponding storage locations indicative of another subscriber line. In this manner, any line associated with the system can communicate with any other line. A trunk interface is provided to enable each subscriber associated with a first switching network as above described to communicate with other subscribers associated with an identical switching network via a communications link or trunk. Also disclosed is a unique data format to enable the use of an asynchronous trunk for communication between two or more switching systems of the above described configuration. The data format enables easy detection and recognition of null characters, control characters and data characters by utilizing a unique eight digit format for each of the above described characters.

Time slot interchanger and control processor apparatus for use in a

An elastic storage circuit employs a first in/first out (FIFO) memory which stores data contained in a serial stream in a plurality of locations, each of which is associated with a unique address. The storage locations operate to store both the data and the address. A word address counter generates a five bit address code to accompany the data bits as stored in the FIFO. If a chronic increase or decrease in the frequency rate of the data occurs, the FIFO will overflow or underflow. This condition is detected by suitable detectors which create an alarm to completely reset the entire contents of the memory and to refill a portion of the memory over a given interval sufficient to permit the system to recover from the slip in the data rate and to thereafter synchronously read the data together with the address identification from the FIFO.

Elastic storage and synchronization control apparatus for use in a

Growing community of inventors

Cary, NC, United States of America

Stephen C Dunning