Abstract:
A broadband communication system (SYS), which is used to distribute television, radio and video signals, is additionally used for transmitting data signals from one subscriber (TN) to another subscriber (TN). The center (ZE) of the broadband communication system (SYS) has a service-on-demand server (SOD) which contains a control facility (CONTROL). The control facility (CONTROL) receives information transmitted by a subscriber (TN) via the return channel (R) to the center, performs a frequency conversion and transmits the information via the downstream channel (V) to all the subscribers (TN) of the broadband communication system (SYS). The information contains a source address, a destination address and the subscriber-specific data to be transmitted. Only subscribers (TN) whose address coincides with the destination address are able to interpret the information through a modem MODEM.
Abstract:
Failures are localized through the use of a Tandem Connection along a segment of a transmission path (P) to be monitored, non-intrusive intermediate Tandem Connection monitors (M), and temporary Tandem Connection sources created along the path segment in the case of a failure (F) in order to forward information about the fault location at least in downstream direction but preferably also in upstream direction. In particular, a failure adjacent network element (N3) detects the failure and activates a temporary tandem connection source function (TS3d, TS3u). This function creates a valid tandem connection signal and insert therein a failed link identifier (TTI). The network element (N4) terminating the tandem connection generates an alarm report including the failed link as indicated by the failed link identifier.
Abstract:
Transmission signals in a transport network are multiplexed from traffic streams respectively representing paths. Each path is identified with a path tag and forwarding information is provided in each network element. Failed paths in the network are restored in that the source network element crossconnects the affected traffic stream to an alternate output port and subsequent network elements receiving this unexpected traffic stream at an input port check the received path tag, determine an appropriate output port based on the tag and the forwarding information, and establish an internal cross-connection between the input port and corresponding output port.
Abstract:
A burst mode optical signal is transported as payload of a framed continuous bit-stream optical signal through an optical transport network. The optical bursts are all generated at a common nominal bitrate which equals substantially the payload bitrate of the continuous bit-stream optical signal. The bursts are converted into a continuous bit stream by filling gaps between the bursts with a predefined pattern. The continuous bit stream thus created is then mapped into frames to generate the framed continuous bit-stream optical signal for transmission.
Abstract:
In order to improve the link adjacency discovery in an Optical Transport Network, a method and related network nodes are provided. A first network node (21) has a first discovery agent (216) and a second network node (22) has a second discovery agent (226). A discovery message (210) is transmitted from a first interface of the first network node (21) over one or more subsequent network links (25, 26, 27) to a second interface of the second network node (22). The discovery message (210) contains information indicative of an discovery agent identifier associated with the first discovery agent (216) and of a termination connection point identifier associated with the first interface. In order to transmit the discovery message (210), the first interface is configured to perform a tandem connection source function (217) using a reserved field in an overhead portion of signal frames to be transmitted. The second interface is configured to perform a Tandem Connection Monitoring function (227) on the same reserved field of received signal frames. The discovery message is sent using a Trail Trace Identifier (TT!) byte available in the reserved field.
Abstract:
A method of restoring an active path between two nodes of a transport network upon occurrence of a failure includes the steps of determining an alternate path through the network and establishing a path protection involving the failed active path and the alternate path. If in layered networks, a failed path is restored at a lower layer and at a higher layer concurrently, the restoration actions in the higher network layer can thus be reverted easily.
Abstract:
The receiver (EMP) according to the invention is characterized, in particular, in that it comprises a control unit (CTRL) by means of which the power consumption of individual modules (1′, 2′, 3′, 4′, 5′, 6′, 7′, 8′) of the receiver (EMP) is reduced as required or can be adjusted to a specified value. In a power-saving mode, only certain modules (1′, 2′, 3′, 4′, 5′, 6′, 7′, 8′) of the receiver (EMP) which are necessary for detecting a specified identifier are supplied with power only for certain time intervals in order to monitor the received data stream in said time intervals. If the receiver (EMP) detects a specified identifier in a specified segment, it switches to normal operation in order also to supply the remaining modules with power and to receive receiver-specific data. In the time intervals between the specified time intervals, all the modules (1′, 2′, 3′, 4′, 5′, 6′, 7′, 8′) are, for example, without operating voltage in the power-saving mode.
Abstract:
In order to improve the link adjacency discovery in an Optical Transport Network, a method and related network nodes are provided. A first network node (21) has a first discovery agent (216) and a second network node (22) has a second discovery agent (226). A discovery message (210) is transmitted from a first interface of the first network node (21) over one or more subsequent network links (25, 26, 27) to a second interface of the second network node (22). The discovery message (210) contains information indicative of an discovery agent identifier associated with the first discovery agent (216) and of a termination connection point identifier associated with the first interface. In order to transmit the discovery message (210), the first interface is configured to perform a tandem connection source function (217) using a reserved field in an overhead portion of signal frames to be transmitted. The second interface is configured to perform a Tandem Connection Monitoring function (227) on the same reserved field of received signal frames. The discovery message is sent using a Trail Trace Identifier (TT!) byte available in the reserved field.
Abstract:
Failures are localized through the use of a Tandem Connection along a segment of a transmission path (P) to be monitored, non-intrusive intermediate Tandem Connection monitors (M), and temporary Tandem Connection sources created along the path segment in the case of a failure (F) in order to forward information about the fault location at least in downstream direction but preferably also in upstream direction. In particular, a failure adjacent network element (N3) detects the failure and activates a temporary tandem connection source function (TS3d, TS3u). This function creates a valid tandem connection signal and insert therein a failed link identifier (TTI). The network element (N4) terminating the tandem connection generates an alarm report including the failed link as indicated by the failed link identifier.
Abstract:
A burst mode optical signal is transported as payload of a framed continuous bit-stream optical signal through an optical transport network. The optical bursts are all generated at a common nominal bitrate which equals substantially the payload bitrate of the continuous bit-stream optical signal. The bursts are converted into a continuous bit stream by filling gaps between the bursts with a predefined pattern. The continuous bit stream thus created is then mapped into frames to generate the framed continuous bit-stream optical signal for transmission.