Abstract: Disclosed are test methods for testing message paths in communication networks. Also disclosed are redundant network arrangements for rerouting information when faults are detected.

Abstract: A method for operating interface modules in an ATM communications device wherein interface modules which can be specified as active and/or redundant are connected to a central control unit. Control commands provided for this purpose are transmitted approximately simultaneously from the central control unit to the active and the redundant interface module during the establishment and clearing of at least one virtual connection, and the redundant interface module does not acknowledge receipt of the control commands. The load on the interface module is thus dynamically relieved.

Abstract: The invention relates to a method and to an apparatus for optimizing transmission security and failure security in high-bit-rate data networks by via signal line redundancy between the network nodes, such that parallel signal lines can optionally be occupied, or can be switched, as working lines or protection lines, and selectors, bridge circuits, and interface modules are provided at the network node side. According to the invention, each of the parallel signal lines is connected at the network node side with a respective interface module, and all interface modules are in principle in the active state. Given failure of one of the interface modules, this failure is immediately countered by a signal line changeover, and line errors are immediately countered by the provided interface module redundancy. Furthermore, error messages can be transmitted, via a corresponding link, between the interface modules of the incoming and outgoing parallel signal lines in each of the network nodes.

Abstract: In the Prior Art, a higher-ranking mechanism controls the standby circuiting of assemblies in 1:N redundancy, resulting in a system dynamics loss. The invention solves this problem in that the devices responsible for the standby circuiting events in the higher-ranking mechanism are relocated into a standby circuit assembly of the 1:N redundancy provided for standby circuiting purposes. The standby circuit events are thus controlled and monitored by the standby circuit assembly itself, relieving the higher-ranking mechanism of these tasks.

Abstract: Disaster recovery of an IP network having a working area, which includes at least a switch for routing traffic through the IP network, is provided. A first mode (402) is provided wherein the working area is active and routes traffic through the IP network, a backup area that has a functionality to route the traffic through the IP network, the backup area is maintained in standby and IP addresses relating to the traffic are stored in a storage area. A second mode (406) is provided wherein, when the working area is inoperable due to disaster, the backup is activated such that the backup area routes the traffic through the IP network with the IP addresses stored in the storage area.

Abstract: Disclosed are test methods for testing message paths in communication networks. Also disclosed are redundant network arrangements for rerouting information when faults are detected.

Abstract: Different conditions of a module are indicated by means of at least one visual indicator element, for instance in the form of a light emitting diode, mounted visibly on the module. Pressing a repair key initiates a repair condition, in which the actions and control procedures necessary for taking the faulty module out of service are carried out, and also causes a newly inserted module in a module frame to be automatically recognized, prompts a test function and causes the new module to be automatically put into service upon passing a test procedure.

Abstract: The communication device (KE) has a coupling arrangement (ASN) with at least a number N of active line assemblies (BG 1 to BG N), which are respectively connected to a transmission line (LTG 1 to LTG N) and, together with an additional standby line assembly (BG N+1), form a “1:N” redundancy group. In such a “1:N” redundancy group, line-specific switches (S) and selection devices (SEL 1:N) are designed and arranged in such a manner that the selection devices can be replaced without adversely affecting the normal operation of the communication device.