Alcatel

Alcatel USA Sourcing, L.p.

Alcatel Lucent

Dsc Communications Corporation

Dsc Telecom L.p.

Anthony Mazzurco

Joseph A Crossett, Iii

Scott A Thompson

Ioan V Teodorescu

Manouchehr Darabpour

Harry W Hartjes

Pavlina Ennghillis

Richard C Witinski

Stewart W Shankel, Iii

Jie Hu

John K Blake

James G Gray

Thomas W Moore

Ramesh Pillutla

Robert Binh Nguyen

Jimmy Hu

Kameel I Wakim

Sanjay Krishna

Kenneth J Bernica

Esmaeil Dowran

Joseph A Iii Crossett

A communication network is arranged in a ring configuration of network elements () coupled by working spans () associated protection spans (), with multiple rings sharing network elements (and). A shared protection span () is coupled between pairs of shared network elements (and). A matrixin a shared network element (or) can couple any channel from one of the incoming working spans or protection spans to any channel of the shared protection span ().

Common protection architecture for optical network

A telecommunications system () includes a first cross-connect switch () and a second cross-connect switch (). The first cross-connect switch () includes a switching matrix that provides information from a matrix connection to a selector () of an output interface (). The selector () places the information from the switching matrix onto one or both of a working channel () and a protection channel (). The second cross-connect switch () receives the working channel () and the protection channel () at an input interface (). The input interface () includes a selector () that checks a signal quality of the working channel () and the protection channel (). When necessary, the selector () sends a request to the selector () to bridge the working channel () onto the protection channel (). According to the signal quality, the selector () selects one of the working channel () and the protection channel () for transfer to a switching matrix () of the second cross-connect switch (). The selector () avoids creating and deleting matrix connections in the switching matrix () in performing protection switches between the working channel () and the protection channel ().

Method and apparatus for providing network protection at input/output interfaces of a cross-connect switch

A communication network using a ring structure incorporates shared protection channels () to reduce costs in implementing protection spans. The shared protection network elements () use a protocol of conventional messaging to integrate with traditional fully redundant network elements.

Method and apparatus for signalling in a shared protection ring architecture

Optical shared protection ring for multiple spans

A cross-connect switch () uses a matrix () for providing connection paths. The matrix () includes prioritization logic () for receiving connection requests from restoration state machines () (for changing connections responsive to line conditions) and an administrative processor (for changing connections responsive to operator commands). Connection requests from both the restoration state machines () and the administrative processor () are cached in FIFO memories (). When a FIFO memory () stores one or more connection requests, the switching control circuitry is notified by a data ready signal. Logic () inhibits passing of the data ready signal from the FIFO memory () to the switching control () until all restoration connection requests have been serviced.

Cross-connect matrix task prioritizer

An optical cross-connect switch () includes and optical matrixfor passing optical communication data between an origination I/O port () and a destination I/O port (). Control information is passes between the origination I/O port () and the destination I/O port () in transport frames. The transport frames include multiple framing bytes indicative of the start of a frame () and stuff bytes at regular intervals to ensure adequate bit transitions in the control information data stream. Payload bytes carrying control information are positioned between stuff bytes. The stuff bytes have different bit values from the framing bytes in multiple bit positions to allow false framing only if there are multiple bit errors in the stuff frame.

Optical frame format

An apparatus and a method for cross connect matrices includes originating, center and terminating stages in both a main portion and a back-up portion that allows center stages to be switched without causing a framing error. The signal from the main portion is transmitted through both the back-up and main portions of the cross connect matrices such that a terminating line card receives a frame aligned signal from the main and back portions. The terminating line card then switches its output to be the signal produced by the back-up portion with no framing error. In the main portion, the center stage may be switched. After the center stage is switched, the terminating line card can switch again to output the signal from the main portion.

Method and apparatus for errorless path protection and rearrangement

A telecommunications network ( ) includes a plurality of nodes ( ) interconnected in a bidirectional line switched ring configuration ( ). The bidirectional line switched ring configuration ( ) includes a working communication link ( ) and a protection communication link ( ) between each of the plurality of nodes ( ). A particular node ( ) within the telecommunications network ( ) includes a first ring port interface ( ) and a second ring port interface ( ) each coupled to the working communication link ( ) and the protection communication link ( ). The first ring port interface ( ) and the second ring port interface ( ) are coupled by a cross connect matrix ( ). The particular node ( ) may have a protection channel access unit ( ) to terminate control information carried over a protection communication link ( ) of the bidirectional line switched ring configuration ( ). In order to maintain transfer of control information over the bidirectional line switched ring configuration ( ), a dedicated matrix connection ( ) in the cross connect matrix provides a path to pass control information between the first ring port interface ( ) and the second ring port interface ( ).

Method and apparatus for passing control information in a bidirectional line switched ring configuration

In a three stage non-blocking switching matrix ( ), there are originating stages ( ), center stages ( ), and terminating stages ( ). In order to establish matrix connections for either a one input/two output scenario or a two input/one output scenario, a determination must be made as to whether there is a center stage ( ) common to all three ports. If so, then the matrix connection is established through the available center stage ( ). If there is no common center stage ( ) among the three ports, then rearrangement candidates are identified to free up an available center stage. One or more matrix connections are rearranged without affecting live traffic. After rearrangement, the matrix connection for the three ports is established through the freed up center stage ( ).

Method of determining network paths in a three stage switching matrix

A method of trafficking telecommunication signals having various formats, includes providing, at a first network element, a synchronous payload envelope having a first format, the synchronous payload envelope comprising a synchronous path and associated overhead portion and a payload portion, mapping the synchronous payload envelope into a transport signal having a second format without terminating the synchronous path or associated overhead portion of the synchronous payload envelope, and transmitting the transport signal to a second network element over a network supporting the second format.

System and method and trafficking telecommunication signals

A method of performance monitoring telecommunication signals having various formats, includes receiving a plurality of telecommunication signals comprising at least one signal having a first format and at least one signal having a second format, identifying the format of each signal received, and for each signal, proceeding with a performance monitoring activity in accordance with a set of rules associated with the identified format of each signal.

System and method for performance monitoring telecommunication signals having various formats

A metallic bridge (16) is operable to join a first local area network (12) with a second local area network (14). Processor cards (18, 20 and 22) are deployed to provide redundant protection. Processor card (18a) is attached to LAN A (12) and processor card (18b) is attached to LAN B (14). In the event of a single point of failure in either the processor cards (18, 20 and 22) or the local area network media or a power failure, the metallic bridge (16) will open and separate the local area networks (12, 14). Operation will continue on the operable local area network.

Apparatus for isolating a fault on a local area network

A digital desynchronizer device (10) includes an elastic store unit (12) that receives data in an asynchronous manner and synchronously transmits the data in response to a synchronization clock generated by a clock generator (14). The clock generator (14) operates off of a reference oscillator unit (16). The clock generator (14) generates the synchronization clock signal in response to pointer adjustments identified by a pointer movement unit (18). The clock generator (14) also generates the synchronization clock signal in response to mapping jitter identified by a mapping unit (20). The pointer movement unit (18) and the mapping unit (20) identify pointer adjustments and mapping jitter, respectively, independent of each other. The clock generator (14) adjusts a width of a specific pulse bit in response to pointer adjustments identified by the pointer movement unit (18). Clock generator (14) also adjusts a width of a specific bit position, separate from the pulse bit position used for pointer adjustments, in response to mapping jitter identified by the mapping unit (20).

Digital desynchronizer

In a telecommunication system having multiple timing subsystems receiving and distributing redundant timing signals, there is provided a circuitry (8, 100) for aligning first and second redundant timing signals (10, 12, 110, 112) and switching therebetween. The circuitry includes first and second phase-locked loops (18, 20, 118, 120) for receiving first and second redundant timing signals (10, 12, 110, 112), respectively, and multiplying the frequency of first and second redundant timing signals (10, 12, 110, 112) by a factor of N. The circuitry further includes a selecting and switching circuitry (34, 134) for receiving the multiplied first and second redundant timing signals (22, 23, 122, 124) and designating one as ACTIVE and the other as INACTIVE, and providing the ACTIVE timing signal as an output timing reference signal (54, 154). The selecting and switching circuitry further operating to switch the ACTIVE and INACTIVE timing signal designations and output timing reference signal in response to detecting a fault or a clock switching command. The ACTIVE timing signal is provided to a phase integrator (40, 140), which integrates phase transients out of the ACTIVE timing signal to avoid jitter in the output timing reference (54, 154).

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Plano, TX, United States of America

Anthony Mazzurco