Abstract: Asynchronous/plesiochronous digital hierarchy (PDH) signals, such as DS1 and E1, are transported using virtual concatenation. The packetized data signals are frame encapsulated and subsequently inverse multiplexed into a plurality of PDH frames. An overhead packet is inserted in the transmitted frames to enable the receiver to determine the status of the frames and extract the differential delay experienced by various frames as they are routed through virtually concatenated channels. The extracted delays enables the receiver to realign the various frames of the PDH signal to reconstitute the originally transmitted signals that travel through different paths of the transport network linking the source and sink of the virtually concatenated channel.

Abstract: A fiber channel (FC) signal representing block encoded data is applied to a block decoder, which removes the block encoding from the data. The data is then applied to a simplified data link (SDL) protocol encoder, which maps the data into an SDL protocol packet for transmission over a SONET (Synchronous Optical Network)-based transport medium.

Abstract: A fibre channel (FC) signal representing block encoded data is applied to a block decoder, which removes the block encoding from the data. The data is then applied to a simplified data link (SDL) protocol encoder, which maps the data into an SDL protocol packet for transmission over a SONET (Synchronous Optical Network)-based transport medium.

Abstract: A communications system includes N parallel communications channels connecting first and second devices. The N channels may include N−1 channels for carrying information symbols, and an Nth channel for facilitating deskewing and word framing. The first device may include an alignment symbol generator for generating alignment symbols on the Nth channel, and a word framing code generator for generating word framing codes on the Nth channel. The second device may include a deskewer for aligning received information symbols based upon the alignment symbols, and a word framer for determining word framing based upon the word framing codes. The word frame code generator in the first device or transmitter, and the word framer in the second device or receiver provide the desired feature of knowledge of where each word starts or begins. The start of each word may be determined in terms of a time and a corresponding one of the N−1 channels where the word starts.

Abstract: A communications system includes N parallel communications channels connecting first and second devices. The N channels may include N-1 channels for carrying information symbols, and an Nth channel for facilitating deskewing and word framing. The first device may include an alignment symbol generator for generating alignment symbols on the Nth channel, and a word framing code generator for generating word framing codes on the Nth channel. The second device may include a deskewer for aligning received information symbols based upon the alignment symbols, and a word framer for determining word framing based upon the word framing codes. The word frame code generator in the first device or transmitter, and the word framer in the second device or receiver provide the desired feature of knowledge of where each word starts or begins. The start of each word may be determined in terms of a time and a corresponding one of the N-1 channels where the word starts.