Abstract: This application discloses a block group loss determining method and an apparatus. The method includes: A transmit end obtains at least two block groups, and sends the at least two block groups to a receive end. The receive end receives the at least two block groups, obtains a receiving quantity of first block groups between a first boundary block group and a second boundary block group in the at least two code groups, then obtains a target quantity of first block groups between the first boundary block group and the second boundary block group, and determines a quantity of lost block groups based on the receiving quantity and the target quantity.

Abstract: A method of operating a network that contains a plurality of nodes is disclosed. The plurality of nodes include a first node and a second node with the first and second nodes being connected via a first path and a second path that are different. The method includes operating the network in first and second modes of operation. In the first mode, traffic between the first and second nodes is transmitted over the first path and not the second path. In the second mode, traffic is transmitted over the first and second paths. The mode of operation is selected based upon a level of traffic between the first and second nodes.

Abstract: A method for adjusting bandwidth in a communications network having a plurality of nodes connected over multiple links with a plurality of services running on the links includes detecting an impairment of a link wherein the impairment invokes a reduction in bandwidth available to the services running on the link, communicating information about the impairment to other nodes in the network and redistributing services between the links to limit a bandwidth required by services running on the impaired link to a value not exceeding the bandwidth available on the impaired link.

Abstract: A method for adjusting bandwidth in a communications network having a plurality of nodes connected over multiple links with a plurality of services running on the links includes detecting an impairment of a link wherein the impairment invokes a reduction in bandwidth available to the services running on the link, communicating information about the impairment to other nodes in the network and redistributing services between the links to limit a bandwidth required by services running on the impaired link to a value not exceeding the bandwidth available on the impaired link.

Abstract: A method of operating a network that contains a plurality of nodes is disclosed. The plurality of nodes include a first node and a second node with the first and second nodes being connected via a first path and a second path that aer different. The method includes operating the network in first and second modes of operation. In the first mode, traffic between the first and second nodes is transmitted over the first path and not the second path. In the second mode, traffic is transmitted over the first and second paths. The mode of operation is selected based upon a level of traffic between the first and second nodes.

Abstract: A method for adjusting bandwidth in a communications network having a plurality of nodes connected over multiple links with a plurality of services running on the links includes detecting an impairment of a link wherein the impairment invokes a reduction in bandwidth available to the services running on the link, communicating information about the impairment to other nodes in the network and redistributing services between the links to limit a bandwidth required by services running on the impaired link to a value not exceeding the bandwidth available on the impaired link.

Abstract: A method of operating a network that contains a plurality of nodes is disclosed. The plurality of nodes include a first node and a second node with the first and second nodes being connected via a first path and a second path that are different. The method includes operating the network in first and second modes of operation. In the first mode, traffic between the first and second nodes is transmitted over the first path and not the second path. In the second mode, traffic is transmitted over the first and second paths. The mode of operation is selected based upon a level of traffic between the first and second nodes.

Abstract: A method for adjusting bandwidth in a communications network having a plurality of nodes connected over multiple links with a plurality of services running on the links includes detecting an impairment of a link wherein the impairment invokes a reduction in bandwidth available to the services running on the link, communicating information about the impairment to other nodes in the network and redistributing services between the links to limit a bandwidth required by services running on the impaired link to a value not exceeding the bandwidth available on the impaired link.

Abstract: A method for adjusting bandwidth in a communications network having a plurality of nodes connected over multiple links with a plurality of services running on the links includes detecting an impairment of a link wherein the impairment invokes a reduction in bandwidth available to the services running on the link, communicating information about the impairment to other nodes in the network and redistributing services between the links to limit a bandwidth required by services running on the impaired link to a value not exceeding the bandwidth available on the impaired link.

Abstract: A method for adjusting bandwidth in a communications network having a plurality of nodes connected over multiple links with a plurality of services running on the links includes detecting an impairment of a link wherein the impairment invokes a reduction in bandwidth available to the services running on the link, communicating information about the impairment to other nodes in the network and redistributing services between the links to limit a bandwidth required by services running on the impaired link to a value not exceeding the bandwidth available on the impaired link.

Abstract: A method of operating a network that contains a plurality of nodes is disclosed. The plurality of nodes include a first node and a second node with the first and second nodes being connected via a first path and a second path that are different. The method includes operating the network in first and second modes of operation. In the first mode, traffic between the first and second nodes is transmitted over the first path and not the second path. In the second mode, traffic is transmitted over the first and second paths. The mode of operation is selected based upon a level of traffic between the first and second nodes.

Abstract: A network (1) comprising a plurality of nodes (2, 3, 4), the plurality of nodes comprising a first node (A) and a second node (B), the first (A) and second (B) nodes being connected through the network of nodes (1) via a first path (2) and a second path (3), the first and second paths being different, in which the network (1) has first and second modes of operation, a first mode (108) in which traffic between the first and second nodes is transmitted over the first path (2) and not the second path (3), and a second mode (106) where the traffic is transmitted over the first (2) and second (3) paths, wherein the network (1) comprises a mode selector (10) arranged to select the mode of operation based upon a demanded level of traffic between the first (A) and second (B) nodes.

Abstract: A digital cross-connect (DXC) (10) comprises: a plurality of ports (30-100) for receiving/outputting signals and switching and switching means (20) for selectively cross-connecting signals applied to one port to one or more other ports. The cross-connect (10) is characterized in that the switching means (20) comprises a single switching matrix which is arranged to be capable of switching Optical Data Units (ODU). Alternatively or in addition the switching matrix is arranged to be capable of transparently switching complete Synchronous Digital Hierarchy (SDH) synchronous transport modules STM-N and/or complete SONET synchronous transport transport signal STS-N derived from optical carriers OC-N and/or SDH vitual containers VC-3, VC-4, and/or concatenated virtual containers VC4-nc where n=4, 16, 64 or 256 as defined in ITU-Recommendation G.707 and/or SONET synchronous transport system STS-1s, STS-nc where n=3, 12, 48, 192 or 768 as defined in Telcordia GR253.

Abstract: A network (1) comprising a plurality of nodes (2, 3, 4), the plurality of nodes comprising a first node (A) and a second node (B), the first (A) and second (B) nodes being connected through the network of nodes (1) via a first path (2) and a second path (3), the first and second paths being different, in which the network (1) has first and second modes of operation, a first mode (108) in which traffic between the first and second nodes is transmitted over the first path (2) and not the second path (3), and a second mode (106) where the traffic is transmitted over the first (2) and second (3) paths, wherein the network (1) comprises a mode selector (10) arranged to select the mode of operation based upon a demanded level of traffic between the first (A) and second (B) nodes.

Abstract: A digital cross-connect (DXC) (10) comprises: a plurality of ports (30-100) for receiving/outputting signals and switching and switching means (20) for selectively cross-connecting signals applied to one port to one or more other ports. The cross-connect (10) is characterized in that the switching means (20) comprises a single switching matrix which is arranged to be capable of switching Optical Data Units (ODU). Alternatively or in addition the switching matrix is arranged to be capable of transparently switching complete Synchronous Digital Hierarchy (SDH) synchronous transport modules STM-N and/or complete SONET synchronous transport transport signal STS-N derived from optical carriers OC-N and/or SDH vitual containers VC-3, VC-4, and/or concatenated virtual containers VC4-nc where n=4, 16, 64 or 256 as defined in ITU-Recommendation G.707 and/or SONET synchronous transport system STS-1s, STS-nc where n=3, 12, 48, 192 or 768 as defined in Telcordia GR253.

Abstract: A digital cross-connect (DXC) (10) comprises: a plurality of ports (30-100) for receiving/outputting signals and switching and switching means (20) for selectively cross-connecting signals applied to one port to one or more other ports. The cross-connect (10) is characterized in that the switching means (20) comprises a single switching matrix which is arranged to be capable of switching Optical Data Units (ODU). Alternatively or in addition the switching matrix is arranged to be capable of transparently switching complete Synchronous Digital Hierarchy (SDH) synchronous transport modules STM-N and/or complete SONET synchronous transport transport signal STS-N derived from optical carriers OC-N and/or SDH virtual containers VC-3, VC-4, and/or concatenated virtual containers VC-4-nc where n=4, 16, 64 or 256 as defined in ITU-T Recommendation G.707 and/or SONET synchronous transport system STS-1s, STS-nc where n=3, 12, 48, 192 or 768 as defined in Telcordia GR253.

Abstract: A method for the transmission of data in a synchronous digital hierarchy (SDH) network comprising the steps of transmitting to a node of the network a form of data signal from outside the network, converting the signal into a virtually concatenated information structure and transporting the signal through the network in the virtually concatenated information structure; means for carrying out the method and tributary cards arranged and configured to process signals received in contiguously concatenated form to convert them into virtually concatenated form for transfer across the network; thus providing for data transmitted in high-bandwidth, contiguosly concatenated signals (ie VC-4-4c) to be transported across a SDH network, not itself capable of carrying contiguously concatenated signals.

Abstract: A digital cross-connect (DXC) (10) comprises: a plurality of ports (30-100) for receiving/outputting signals and switching and switching means (20) for selectively cross-connecting signals applied to one port to one or more other ports. The cross-connect (10) is characterized in that the switching means (20) comprises a single switching matrix which is arranged to be capable of switching Optical Data Units (ODU). Alternatively or in addition the switching matrix is arranged to be capable of transparently switching complete Synchronous Digital Hierarchy (SDH) synchronous transport modules STM-N and/or complete SONET synchronous transport transport signal STS-N derived from optical carriers OC-N and/or SDH vitual containers VC-3, VC-4, and/or concatenated virtual containers VC-4-nc where n=4, 16, 64 or 256 as defined in ITU-T Recommendation G.707 and/or SONET synchronous transport system STS-1s, STS-nc where n=3, 12, 48, 192 or 768 as defined in Telcordia GR253.

Abstract: A synchronous digital hierarchy (SDH) telecommunications system for transporting traffic with control bytes for indicating the sources of the traffic. The system comprises a plurality of interconnected nodes each capable of identifying undeliverable traffic by checking the sources indicated by the control bytes. The system also comprises a network management system (NMS) arranged to provide each node with information concerning the expected sources of the traffic. The system acts to identify undeliverable traffic by comparing the sources indicated by the control bytes with the expected sources.

Abstract: Timing pointer signals to be transmitted across a synchronous digital hierarcy (SDH) network are transmitted in virtual containers (VC) in a number of fixed stuff bytes which were hitherto unused. In a preferred embodiment two such bytes are used to carry the timing information which allows for up to a sixteen bit code to be provided for the timing pointers.