36 results about "Link Capacity Adjustment Scheme" patented technology

The present invention provides methods and apparatuses for interfacing high-layer applications to Link Capacity Adjustment Scheme (LCAS) on Synchronous Optical Network / Synchronous Digital Hierarchy (SONET / SDH) edge nodes. These applications include high-level control protocols, such as Generalized Multiprotocol Label Switching (GMPLS) and Optical Switching and Routing Protocol (OSRP), and user-initiated cross-connect creation and termination. The present invention provides a mechanism that is capable of mapping SONET / SDH connections to Virtual Concatenated Groups (VCGs), thus enabling an efficient interface for operators to control and manage the connections via LCAS. As part of the mechanism, the existing LCAS protocol state machine is enhanced such that the operators can shut down bi-directional SONET / SDH flows from a single edge node, as opposed to from both source and sink nodes, as provided for by existing specifications.

Equipment enables an improved efficiency in network bandwidth usage, and an improved upper-layer throughput even when abrupt change occurs in input traffic. The equipment includes an input traffic collector which collects and retains an input traffic amount of each input port for one period at preset periods; a bandwidth set processor which calculates a bandwidth for use in each input port from the input traffic amount retained in the input traffic collector, and calculates the corresponding number of virtual concatenation member paths from the difference of the bandwidth in use and a virtual concatenation path bandwidth having been allocated to the input port, and issues an addition command or a deletion command for adding or deleting the virtual concatenation member paths for the calculated number; a virtual concatenation controller which sets a virtual concatenation path bandwidth against the traffic input from the plurality of ports; and a link capacity adjustment scheme controller which sets and changes the virtual concatenation to the virtual concatenation controller, based on the addition command or the deletion command of the virtual concatenation member paths issued by the bandwidth set processor.

A system and method provides the capability to provision and setup an end-to-end circuit that does not require the performance of extra, manual management link addition / removal procedures after all facilities and VT / STS cross connections have been provisioned. A method of provisioning a circuit comprises the steps of provisioning an Ethernet port facility, including determining a members of a Link Capacity Adjustment Scheme Virtual Concatenation Group before virtual tributary or synchronous transport signal cross connections are provisioned and before Synchronous Optical Network or Synchronous Digital Hierarchy cross-connections are provisioned; provisioning virtual tributary or synchronous transport signal cross connections; and provisioning Synchronous Optical Network or Synchronous Digital Hierarchy cross-connections.

The transport capacity of a Virtual Concatenation Group (VCG) can be reduced under control of a Link Capacity Adjustment Scheme (LCAS). The VCG comprises link members, in which payload data are transmitted. A first control message comprising a fail message (RFAIL) for a link member is transmitted from sink to source, while the sink continues reception of payload data. On reception of the first control message at the source, a second control message is transmitted comprising a message (FDNU) indicating that payload data of the link member shall not be used, and transmission of payload data is discontinued. On reception of the second control message at the sink reception of payload data is discontinued, and the link member is removed. This allows a reduction of the transport capacity of a Virtual Concatenation Group to be performed in a hitless manner, even when initiated at the sink side.

Disclosed is a method for dynamically and losslessly adjusting bandwidth of an embedded Resilient Packet Ring (RPR) ring network, in which dynamic and lossless bandwidth adjustment for an RPR ring network embedded in a Synchronous Digital Hierarchy (SDH) / Synchronous Optical Network (SONET) can be realized through adding a Link Capacity Adjustment Scheme (LCAS) system in the SDH / SONET processing layer. When it is required to increase ring network bandwidth, the bandwidth of the link section between sites on the SDH / SONET processing layer is first increased. Then the LCAS system in the SDH / SONET processing layer is started, and the actual bandwidth of the link on the SDH / SONET processing layer is increased losslessly with the LCAS system. Finally the bandwidth of the ring network on the RPR processing layer is increased. When it is required to decrease ring network bandwidth, the bandwidth of the ring network on the RPR processing layer is first decreased. Then the LCAS system in the SDH / SONET processing layer is started, and the actual bandwidth of the link on the SDH / SONET processing layer is decreased losslessly with the LCAS system. Finally the bandwidth of the link section between sites on the SDH / SONET processing layer is decreased. With the disclosed method, dynamic and lossless bandwidth adjustment for an embedded RPR ring network in SDH / SONET can be realized.

A communication system and method provide fractional protection of Resilient Packet Ring (RPR) span bandwidth (BW) by provisioning the number of SONET paths in a given span to greater than the RPR ring BW. A communication system comprises a plurality of Synchronous Optical Network paths, a Resilient Packet Ring span implemented using the plurality of Synchronous Optical Network paths, and a Link Capacity Adjustment Scheme operable, in response to failure of a Synchronous Optical Network path implementing the Resilient Packet Ring span, to remove the failed Synchronous Optical Network path from implementing the Resilient Packet Ring span and to redistribute the Resilient Packet Ring traffic over the remaining Synchronous Optical Network paths.

A device determines a high watermark threshold for a subrate service, compares a traffic demand to the high watermark threshold, and adds a temporary bandwidth to an original bandwidth available to the subrate service if the traffic demand is greater than or equal to the high watermark threshold.

The invention includes a method and apparatus for transporting a client signal over a transport network using enhanced virtual concatenation (VCAT) and enhanced link capacity adjustment scheme (LCAS) techniques. A method includes provisioning, for a client signal, a virtual concatenation group (VCG) signal having a VCG signal bandwidth, converting the VCG signal into a set of VCG member signals including a plurality of working VCG member signals and at least one protection VCG member signal where the set of VCG member signals has an aggregate bandwidth greater than the VCG signal bandwidth, and propagating the client signal toward the transport network using the set of VCG member signals. The client signal is initially conveyed by the working VCG member signals, and the at least one protection VCG member signal is available to protect the working VCG member signals. The client signal may be a constant bit rate (CBR) client signal.

The present invention provides methods and apparatuses for interfacing high-layer applications to Link Capacity Adjustment Scheme (LCAS) on Synchronous Optical Network / Synchronous Digital Hierarchy (SONET / SDH) edge nodes. These applications include high-level control protocols, such as Generalized Multiprotocol Label Switching (GMPLS) and Optical Switching and Routing Protocol (OSRP), and user-initiated cross-connect creation and termination. The present invention provides a mechanism that is capable of mapping SONET / SDH connections to Virtual Concatenated Groups (VCGs), thus enabling an efficient interface for operators to control and manage the connections via LCAS. As part of the mechanism, the existing LCAS protocol state machine is enhanced such that the operators can shut down bi-directional SONET / SDH flows from a single edge node, as opposed to from both source and sink nodes, as provided for by existing specifications.

Provided is a multi-layer restoration method using a LCAS (Link Capacity Adjustment Scheme) in a synchronous network having a mesh structure. The method includes: performing a hardware restoration method if a network failure is detected; performing a pre-planned restoration method if the network failure is not repaired by performing the hardware restoration method; determining whether channels that pass along a line where the network failure occurs use the LCAS if the network failure is not repaired by performing the pre-planned restoration method; and applying the LCAS to the channels if the channels are determined to use the LCAS, and performing a dynamic restoration method if the channels are not determined to use the LCAS. The multiplayer restoration method minimizes data loss due to an increase in restoration time and overcomes service disconnection caused by failure to obtain a spare channel.

A member of a Virtual Concatenation Group (VCG) can be temporarily disabled under control of a Link Capacity Adjustment Scheme (LCAS). The VCG comprises a number of link members, in which payload data are transmitted. A management command (MLOCKOUT) is transmitted from a management system to at least one of the source and sink side for one member requesting the member to be temporarily disabled. In response to the management command a forward control message is transmitted from the source side comprising a message (FDNU) indicating that payload data of the member shall not be used, and transmission of payload data for the member is discontinued. In this way temporary disabling of a VCG member is provided, in which it is ensured that the same member is enabled again when the operation requiring the disabling is completed, and which can be handled as a separate function by the management system.

The invention relates to a method for transmitting data in a data network using virtual containers, which are combined to form a virtual concatenated group by means of the Link Capacity Adjustment Scheme, LCAS. The virtual concatenated group is sub-divided on the send side into a first virtual concatenated group and a second virtual concatenated group. Data of a first type is inserted on the sendside into the first virtual concatenated group and data of the second type is inserted into the second virtual concatenated group. Said data is then transmitted via the data network.

The invention includes a method and apparatus for transporting a client signal over a transport network using enhanced virtual concatenation (VCAT) and enhanced link capacity adjustment scheme (LCAS) techniques. A method includes provisioning, for a client signal, a virtual concatenation group (VCG) signal having a VCG signal bandwidth, converting the VCG signal into a set of VCG member signals including a plurality of working VCG member signals and at least one protection VCG member signal where the set of VCG member signals has an aggregate bandwidth greater than the VCG signal bandwidth, and propagating the client signal toward the transport network using the set of VCG member signals. The client signal is initially conveyed by the working VCG member signals, and the at least one protection VCG member signal is available to protect the working VCG member signals. The client signal may be a constant bit rate (CBR) client signal.

The invention discloses a convergent protocol converter and a transceiving method thereof for automatically recognizing high-level data link control (HDLC) / generic framing procedure (GFP) user side protocol converters. An HDLC / GFP automatic processing module is arranged between an ethernet data-caching module and a virtual concatenate (VCAT) and link capacity adjustment scheme (LCAS) module, thereby automatic HDLC and GFP framing / deframing of a local side single convergent converter is achieved, the transmission of information with multiple far-end single way, multiple ways, HDLC type or GFP type E1 protocol converters is achieved, by means of the mode, the automatic identification can be performed when the user side changes different types of protocol converters, and a system which is high in cost performance ratio and compatibility and convenient to install and maintain can be flexibly achieved.

Methods for extracting packetized data from a SONET / SDH signal include processing the signal to produce a deskewed data stream; demapping the data stream to produce a stream of packets; and temporarily storing the packets in a packet buffer, wherein the demapping is performed at a first rate when the fullness of the buffer is below a fullness threshold and the demapping is performed at a second rate when the fullness of the buffer is at or above the fullness threshold. Apparatus for performing the methods are also disclosed.