Abstract: Network elements of a first synchronous transport network are to be connected to one another via a second synchronous transport network. For this purpose a frame (STM-4) to be transmitted, including the unchanged overhead sections (MS-OH, RS-OH, AU-PTR) thereof, is packed as payload in a concatenation (VC-4-5v) of newly formed multiplex units (VC-4v) and transmitted in newly formed transport modules via the second transport network.

Abstract: A method is disclosed for transmitting data packets in wide area networks (WAN) by way of a synchronous digital data transmission network (SDH), wherein the data packets are packed into synchronous transport modules (STM-N) and are transmitted by way of virtual connections formed by subunits of synchronous transport modules of the same size. The virtual connections are entered into an address table and an evaluation of the target address of the data packets takes place in one of the network elements of the synchronous digital data transmission network. On the basis of the address table and the target address, at least for a part of the data packets, a decision is made by at least one of the network elements of the synchronous digital data transmission network as to which one of the virtual connections is used to transmit this data packet. Furthermore, a network element is disclosed, which operates in accordance with the transmission method.

Abstract: A method of operating a data transmission network (10) is described comprising at least two outer rings (11, 13) and a middle ring (12) which are coupled to one another via nodes (14, 15, 16). One of the nodes (14) represents a central node for all three rings (11, 12, 13). Switching devices (23, 24, 25, 26) for the establishment of connections are contained in each of the nodes (14, 15, 16). It is recognized that a connection is to be established from the one outer ring (11, 13) to the other outer ring (13, 11) via the middle ring (12). Then the connection is established taking into account all three rings (11, 12, 13).

Abstract: Network elements such as digital crossconnects are provided with a 1:1 redundancy of, among other things, the switching matrix in order to maintain their functionality in the event of a hardware failure. Against disasters such as fires, explosions, or floods in which all equipment in a room is destroyed, the redundancy used in prior-art network elements can afford no protection. To remedy this, the two switching matrices (21, 22), which are present anyhow, are installed in separate rooms (31, 32), i.e., a single network element is divided between two rooms. To this end, the interface modules (23, 24) are divided into two groups, and each of the groups is assigned to a respective one of the switching matrices. A respective one of the switching matrices and a respective one of the groups of interface modules are arranged in, e.g.

Abstract: In a method of transmitting user data over a synchronous digital communication network (SDH), the user data are packed in multiplex units by a peripheral device (10; 40). If a greater bandwidth than the capacity of the multiplex unit is required, several multiplex units are contiguously concatenated (VC-4-4c) and transmitted in a common transport module (STM-4). At the gateway to the synchronous communication network, the contiguous concatenation of the multiplex units (VC-4-4c) is converted to a virtual concatenation of multiplex units (VC-4-Nv). To adapt the number of concatenated multiplex units to the bandwidth actually required, only part of the multiplex units are filled with user data, and during the conversion, those multiplex units which are not filled with user data are omitted.

Abstract: SONET and SDH signals are framed multiplex signals which are composed of multiplex units according to a respective specified multiplex hierarchy, such that smaller multiplex units are multiplexed in larger multiplex units and that the larger multiplex units are transmitted in frames. Compared to the multiplex hierarchy of SONET, the multiplex hierarchy of SDH has an additional level, namely the VC-4. A method of converting a SONET signal to an SDH signal is disclosed in which the multiplex units of the SONET signals are converted to corresponding multiplex units of the SDH signal, which are multiplexed into multiplex units of the additional hierarchy level. Monitoring functions are applied to both signals in accordance with the SDH multiplex hierarchy. In applying the monitoring functions to the SONET signal, the additional level of the SDH multiplex hierarchy is simulated by setting parameters to be monitored to default values.

Abstract: A method of establishing logical connections in a synchronous communications network (SDH) comprising a plurality of at least partially interconnected network elements (NE1, NEn; CC1-CC3) and designed for the transmission of data packets containing a destination address involves monitoring destination addresses of the data packets to be transmitted, determining the traffic volume between the individual network elements (NE1, NEn; CC1-CC3) with the aid of the destination addresses, and determining an optimized configuration of logical connections based on the traffic volume and existing logical connections. In this manner, the communications network is adapted to the current traffic situation, and the transmission capacities of the network are utilized in the best possible manner. The monitoring is advantageously done in at least part of the network elements, while the determination of the traffic volume and the optimized configuration is performed by a central management system (TMN).

Abstract: A method is proposed for transmitting virtual containers of SDH or SONET signals in which a group of AU-3s or AU-4s or AU-3-Nc's or AU-4-4c's is transmitted in a novel VC-Y-Xc transport module having an AU-PTR and an AU-POH for the group. The VC-Y-Xc transport module for SDH or SONET serves to form a group of virtual containers and has a PTR for the group, a POH for the group and a maximum of X-1 virtual container locations for transmitting tributary bits, where X is a natural number greater than 1 and Y is equal to 3 or 4 or a natural number greater than 1. For higher-order transmission channels, for example, VC-4s or VC-3s or also VC-4-Nc's or VC-3-3Nc's, a channel bundling is performed if said channels are transported jointly at least over a subsection. The network management has only to manage, to protect and to switch the one bundle instead of a multiplicity of individual channels.

Abstract: A method is disclosed for transmitting data packets in wide area networks (WAN) by way of a synchronous digital data transmission network (SDH), wherein the data packets are packed into synchronous transport modules (STM-N) and are transmitted by way of virtual connections formed by subunits of synchronous transport modules of the same size. The virtual connections are entered into an address table and an evaluation of the target address of the data packets takes place in one of the network elements of the synchronous digital data transmission network. On the basis of the address table and the target address, at least for a part of the data packets, a decision is made by at least one of the network elements of the synchronous digital data transmission network as to which one of the virtual connections is used to transmit this data packet. Furthermore, a network element is disclosed, which operates in accordance with the transmission method.

Abstract: A method of operating a data transmission network (10) is described comprising at least two outer rings (11, 13) and a middle ring (12) which are coupled to one another via nodes (14, 15, 16). One of the nodes (14) represents a central node for all three rings (11, 12, 13). Switching devices (23, 24, 25, 26) for the establishment of connections are contained in each of the nodes (14, 15, 16). It is recognized that a connection is to be established from the one outer ring (11, 13) to the other outer ring (13, 11) via the middle ring (12). Then the connection is established taking into account all three rings (11, 12, 13).

Abstract: Network elements of a first synchronous transport network are to be connected to one another via a second synchronous transport network. For this purpose a frame (STM-4) to be transmitted, including the unchanged overhead sections (MS-OH, RS-OH, AU-PTR) thereof, is packed as payload in a concatenation (VC-4-5v) of newly formed multiplex units (VC-4v) and transmitted in newly formed transport modules via the second transport network.

Abstract: A method is disclosed for transmitting data packets in wide area networks (WAN) by way of a synchronous digital data transmission network (SDH), wherein the data packets are packed into synchronous transport modules (STM-N) and are transmitted by way of virtual connections formed by subunits of synchronous transport modules of the same size. The virtual connections are entered into an address table and an evaluation of the target address of the data packets takes place in one of the network elements of the synchronous digital data transmission network. On the basis of the address table and the target address, at least for a part of the data packets, a decision is made by at least one of the network elements of the synchronous digital data transmission network as to which one of the virtual connections is used to transmit this data packet. Furthermore, a network element is disclosed, which operates in accordance with the transmission method.

Abstract: A method of establishing logical connections in a synchronous communications network (SDH) comprising a plurality of at least partially interconnected network elements (NE1, NEn; CC1-CC3) and designed for the transmission of data packets containing a destination address involves monitoring destination addresses of the data packets to be transmitted, determining the traffic volume between the individual network elements (NE1, NEn; CC1-CC3) with the aid of the destination addresses, and determining an optimized configuration of logical connections based on the traffic volume and existing logical connections. In this manner, the communications network is adapted to the current traffic situation, and the transmission capacities of the network are utilized in the best possible manner. The monitoring is advantageously done in at least part of the network elements, while the determination of the traffic volume and the optimized configuration is performed by a central management system (TMN).

Abstract: In a method of transmitting user data over a synchronous digital communication network (SDH), the user data are packed in multiplex units by a peripheral device (10; 40). If a greater bandwidth than the capacity of the multiplex unit is required, several multiplex units are contiguously concatenated (VC-4-4c) and transmitted in a common transport module (STM-4). At the gateway to the synchronous communication network, the contiguous concatenation of the multiplex units (VC-4-4c) is converted to a virtual concatenation of multiplex units (VC-4-Nv). To adapt the number of concatenated multiplex units to the bandwidth actually required, only part of the multiplex units are filled with user data, and during the conversion, those multiplex units which are not filled with user data are omitted.