Abstract: A logical services loopback framework for establishing transparent loopback connections and associations across Layer-2 networks is provided. The loopback framework operates as a termination/processing point for Transport, Connectivity and Services OAM flows. As a termination/processing point, the disclosed loopback framework realizes connections and associations that are used to transparently test and monitor various layers, such as OSI-specified protocol layers, policy-enabled layers, and/or business-oriented layers.

Abstract: A network interface card and system incorporating the interface card with hardware link failure detect circuitry and operating system compliant driver and GUI management software and system operator selectable delay, to provide soft fail-over transfer from the primary to a secondary network link port without data loss. The systems comprising the multi-port interface card according to the present invention provide a single network and redundant paths with optional conversion to different data medium, e.g. between fiber optic and twisted pair, and also comprises multi-network configurations connecting common equipment having the multi-port interface card according to the present invention therein.

Abstract: A circuit is provided for forming fixed length blocks of information units received from one network for transfer to another. The actual information from each serially received information unit is stored in a receive buffer. A block header register is provided to store the logical channel number, block byte count, and a bit map having locations corresponding with each of the actual information units stored in the receive buffer. Once all of the information units have been received, the header register provides its output to the receive buffer for storage in a header location. The receive buffer thus forms a fixed length block which can be transferred to another network for processing.