Abstract: A method and apparatus in which a data stream is received that includes constant bit rate (CBR) carrier streams, at least one of which comprises frames, a cumulative phase offset report (CPOR) and a client rate report (CRR). A counter accumulating a PHY-scaled stream clock (IPSCk) is sampled at a nominal sampling period (Tps) to obtain a cumulative PHY-scaled count (CPSC). A PHY-scaled stream phase offset (PSPO) is calculated that indicates phase difference between PHY-scaled stream nominal bit count (LPSD) and an incoming PHY-scaled count delta (IPSD). The data stream is demultiplexed to obtain CBR carrier streams. Respective CBR carrier streams include a previous network node CPOR (CPOR-P) and a previous network node CPO (CPO-P). A CPO is calculated that is a function of CPO-P and PSPO. CPO-P is replaced with the calculated CPO. The CBR carrier streams are multiplexed into intermediate-network-node data streams that are transmitted from the intermediate-network-node.

Abstract: A method and apparatus includes receiving at a sink node a path signal frame and a modified set of idle character 64B/66B blocks. The path signal frame includes encoded client data signal 64B/66B blocks, path overhead 64B/66B data blocks and a control 64B/66B block. The link bit rate is measured. The number of idle character 64B/66B blocks is determined. The data blocks of the CBR client signal are extracted from the encoded client data signal 64B/66B blocks and the CBR client signal is regenerated from the extracted data blocks. A bit rate of the CBR client signal is determined using the measured link bit rate and the number of idle character 64B/66B blocks. The rate of a CBR signal clock is adjusted for transmitting the CBR client signal at the determined bit rate.

Abstract: A system and method for performing rate adaptation of constant bit rate (CBR) client data for transmission over a Metro Transport Network (MTN) by defining a plurality of pseudo-Ethernet packets at a source node, assembling a plurality of Generic Mapping Procedure (GMP) frames by mapping a plurality of blocks from a stream of encoded blocks of CBR client data, a plurality of pad blocks, and GMP overhead into consecutive pseudo-Ethernet packets of the plurality of pseudo-Ethernet packets, inserting a fixed number of idle blocks between one or more of the consecutive pseudo-Ethernet packets and inserting an MTN path overhead (POH) frame that is aligned to the plurality of GMP frames to generate a plurality of rate adapted GMP frames for transmission over the MTN to an intermediate node or a sink node.

Abstract: A system and method for performing rate adaptation of constant bit rate (CBR) client data for transmission over a Metro Transport Network (MTN) by defining a plurality of pseudo-Ethernet packets at a source node, assembling a plurality of Generic Mapping Procedure (GMP) frames by mapping a plurality of blocks from a stream of encoded blocks of CBR client data, a plurality of pad blocks, and GMP overhead into consecutive pseudo-Ethernet packets of the plurality of pseudo-Ethernet packets, inserting a variable number of idle blocks between one or more of the consecutive pseudo-Ethernet packets and inserting an MTN path overhead (POH) frame that is aligned to the plurality of GMP frames to generate a plurality of rate adapted GMP frames for transmission over the MTN to an intermediate node or a sink node.

Abstract: A method and apparatus in which a data stream generated by a previous network node, a cumulative phase offset report (CPOR) and a client rate report (CRR) are received. A counter accumulating a PHY-scaled stream clock (IPSCk) is sampled at a nominal sampling period (Tps) to obtain a cumulative PHY-scaled count (CPSC). A PHY-scaled stream phase offset (PSPO) is calculated that indicates phase difference between a PHY-scaled stream nominal bit count (LPSD) and an incoming PHY-scaled count delta (IPSD), where IPSD indicates CPSC increment between successive CPSC samples. The data stream is demultiplexed to obtain CBR carrier streams that include a previous network node CPOR (CPOR-P) and a previous network node CPO (CPO-P). A CPO is calculated that is a function of CPO-P and the PSPO. CPO-P is replaced with the calculated CPO. The CBR carrier streams are multiplexed into intermediate-network-node data streams that are transmitted from the intermediate-network-node.

Abstract: A source node for rate adapting a constant bit rate client signal into a signal stream in a 64B/66B-block telecom signal communication link includes a GMP engine; a FIFO buffer coupled to receive a 64B/66B encoded client data stream; a clock rate measuring circuit; a source of 64B/66B path overhead blocks; a source of 64B/66B pad blocks; a source of 64B/66B idle blocks; a multiplexer; and a multiplexer controller. A control 64B/66B block is encoded into an ordered set block-designator and a count of data blocks to be sent in a next path signal frame is encoded into a plurality of path overhead 64B/66B data blocks. The multiplexer controller is responsive to a count of data blocks to be sent in a next path signal frame from a previous GMP window frame to selectively pass data to a data output so as to fill a GMP window frame.

Abstract: A method for rate adapting a constant bit rate (CBR) client signal into a signal stream in a telecom signal communication link includes at a source node encoding into a control block a control block header, and an ordered set block-designator, encoding into a plurality of path overhead data blocks a data block header and a count of data blocks to be encoded in a signal block, encoding into each of a plurality of signal blocks a data block header, the data blocks from the CBR signal equal to the count and pad blocks, assembling the blocks into a path signal frame, appending a set of idle character blocks following the end of the path signal frame to match a link bit rate of a first link segment, and transmitting the path signal frame and idle character blocks into the first link segment at the link bit rate.

Abstract: A method for extracting path overhead (POH) data blocks from a data stream in a 64B/66B-block communication link, the method includes receiving at a sink node a data stream in a 64B/66B-block communication link, detecting within the data stream at a PCS sublayer a micro-packet starting with an /S/ control block, including K POH data blocks, and ending with a /T/ control block, extracting the micro-packet from the data stream, and extracting the POH data blocks from the micro-packet.

Abstract: A method for extracting POH data blocks and a MOS control block from a data stream in a 64B/66B-block communication link including receiving a data stream, finding a first combination of a MOS control block and K POH data blocks including CRC data in the data stream, extracting the MOS control block and the K POH data blocks from the data stream, searching in a window for a subsequent combination of a MOS control block and K POH data blocks and removing them if at least one of them are found, if neither the subsequent MOS control block nor the K POH data blocks are found within the predetermined window, extracting from the data stream K+1 64B/66B-blocks in the predetermined window.

Abstract: A method for rate adapting a constant bit rate (CBR) client signal into a signal stream in a telecom signal communication link includes at a source node encoding into a control block a control block header, and an ordered set block-designator, encoding into a plurality of path overhead data blocks a data block header and a count of data blocks to be encoded in a signal block, encoding into each of a plurality of signal blocks a data block header, the data blocks from the CBR signal equal to the count and pad blocks, assembling the blocks into a path signal frame, appending a set of idle character blocks following the end of the path signal frame to match a link bit rate of a first link segment, and transmitting the path signal frame and idle character blocks into the first link segment at the link bit rate.

Abstract: A system and method for block-code transcoding. An input signal is analyzed to determine if the input signal includes multiple control words, multiple data words and a single control word or only data words. If the input signal comprises multiple control words, the method includes, generating a control word location map and mapping the control codes and any data words to a block-code encoded transmission signal. If the input signal comprises a single control word and multiple data words, the method includes, generating a control word location address indicating a location of the single control word and mapping the control code and the multiple data words to a block-code encoded transmission signal. If the input signal comprises only data words, the method includes, mapping the data words sequentially into the block-code encoded transmission signal.

Abstract: A frame delineation method for a generic framing procedure (GFP) that includes: searching a serial data stream comprising GFP frames, octet by octet, to identify an eight octet sequence; and delineating GFP frames from the serial data stream in response to determining that a first group of four octets of the identified eight octet sequence comprises a valid Core Header, and in response to determining that a second group of four octets of the identified eight octet sequence comprises one of a valid Core Header and a valid descrambled Type Header.

Abstract: A system and method for block-code transcoding. An input signal is analyzed to determine if the input signal comprises multiple data words and multiple control words, multiple data words and a single control word or multiple data words only. If the input signal comprises multiple control words, the method includes, generating a control word location map and mapping the control codes and data words to a block-code encoded transmission signal. If the input signal comprises a single control word, the method includes, generating a control word location address indicating a location of the single control word and mapping the control word and the data words to a block-code encoded transmission signal. If the input signal comprises multiple data words only, the method includes, mapping the multiple data words sequentially into the block-code encoded transmission signal.

Abstract: A system and method for block-code transcoding. An input signal is analyzed to determine if the input signal includes multiple control words, multiple data words and a single control word or only data words. If the input signal comprises multiple control words, the method includes, generating a control word location map and mapping the control codes and any data words to a block-code encoded transmission signal. If the input signal comprises a single control word and multiple data words, the method includes, generating a control word location address indicating a location of the single control word and mapping the control code and the multiple data words to a block-code encoded transmission signal. If the input signal comprises only data words, the method includes, mapping the data words sequentially into the block-code encoded transmission signal.

Abstract: A frame delineation method for a generic framing procedure (GFP) that includes: searching a serial data stream comprising GFP frames, octet by octet, to identify an eight octet sequence; and delineating GFP frames from the serial data stream in response to determining that a first group of four octets of the identified eight octet sequence comprises a valid Core Header, and in response to determining that a second group of four octets of the identified eight octet sequence comprises one of a valid Core Header and a valid descrambled Type Header.

Abstract: A frame delineation method for a generic framing procedure (GFP) that includes: searching a serial data stream comprising GFP frames, octet by octet, to identify an eight octet sequence; and delineating GFP frames from the serial data stream in response to determining that a first group of four octets of the identified eight octet sequence comprises a valid Core Header, and in response to determining that a second group of four octets of the identified eight octet sequence comprises one of a valid Core Header and a valid descrambled Type Header.

Abstract: A method and apparatus are provided for generating Generic Mapping Procedure (GMP) stuff/data decisions, which avoids brute force modulo arithmetic and is efficient for hitless adjustment of ODUFIex (G.7044) in an Optical Transport Network (OTN). Addition operations are used, rather than multiplication operations, to facilitate faster and less computationally expensive calculation of data/stuff decisions, based on calculated residue values. Residue values are logically arranged in rows to facilitate residue calculation, such as based on relationships with previously calculated residue values. This method is also applicable for mapping and de-mapping Constant Bit Rate (CBR) clients into and from an ODUk carrier.

Abstract: Methods and systems are provided for controlling elements in a signal path of a communication network to accommodate changes in the rate of a client signal. In particular, during the bandwidth resizing (BWR) portion of ITU-T Recommendation G.7044 Hitless Adjustment of ODUflex(GFP) protocol (HAO), the nodes in the chain along the ODUflex(GFP) signal path change their output rates in parallel such that FIFO over/underflow is avoided in the nodes. Certain embodiments provide mechanisms to synchronize and stabilize the nodes in a verifiable manner.

Abstract: A method of communicating count value information in an Optical Transport Network (OTN) signal frame. The method comprises determining a count value indicating a number of payload bytes to be sent in a next OTN signal frame; determining that a change in the count value (?) with respect to a current count value is within a predetermined range; selecting an inversion pattern indicating the change in the count value; determining a cyclic redundancy check (CRC) code associated with the inversion pattern; and, inserting the inversion pattern and the CRC code in a Generic Mapping Procedure (GMP) overhead of the OTN signal frame.

Abstract: Signature circuits are used during testing of an integrated circuit. Test vectors are applied as inputs to a circuit under test. A signature circuit stores a “signature” for the circuit under test based on a combination of signals from the circuit under test in response to test vectors and a previous stored state of the signature register. The value contained in the signature register at the end of the test is the signature. A fault-free circuit generates a particular signature for the applied test vectors. Faults can be determined by detecting variances from the expected signature. In one embodiment, the signature circuit uses a combination of two error detection codes.