Abstract: One embodiment of the invention provides a method of operating a switch in a communications network. The method includes storing a set of routings for each port in the switch. When a packet is received at a port in the switch, the set of routings corresponding to the port at which the packet was received is accessed. A port from which to forward the packet from the switch is determined in accordance with the set of routings. The packet is then duly forwarded over the network from the port as determined by the routings.

Abstract: An Infiniband device can be provided. The device can comprise an input port having a serialiser/deserialiser. The serialiser/deserialiser can comprise: a data buffer for storing data from a received serial data stream and for outputting the stored data in parallel groups and a code detector for detecting a predetermined code pattern in the serial data stream and generating a code detection output in response thereto. The serialiser/deserialiser can also comprise a transition detector for detecting transitions in the serial data stream and reconstructing a serial data clock therefrom, and for generating a plurality of parallel data clocks from the serial data clock, each parallel data clock having a different phase. The data buffer can be responsive to the code detection output to adjust a parallel data group start position within the serial data stream and to cause a selection of one of the reduced frequency clocks having a phase corresponding to the adjusted parallel data group start position.

Abstract: One embodiment of the invention provides a method of operating a switch with cut-through routing in a communications network. The method includes receiving a packet at a first port of the switch and determining a second port of the switch from which the received packet is to be forwarded out over the network. At least one authentication check is performed on the received packet. In general, the switch starts to forward the received packet from the second port prior to complete reception of the packet at the first port. However, this onward transmission is delayed until the authentication check has completed. This ensure that none of the received packet is forwarded from the second port if any authentication check fails.

Abstract: A receiver for digital data is provided. The receiver comprises a ring buffer operable to store received data. The receiver also comprises a write pointer controller for the buffer, operable to control the writing of received data into the buffer, and a read pointer controller for the buffer, operable to control the reading of data from the buffer. The receiver further comprises a pointer adjustment controller operable, in response to a detection of a special data indicator, to control at least one of the write pointer controller and the read pointer controller using forward looking operable to foresee a data location within the buffer corresponding to a future read location of the buffer.

Abstract: A verification process comprises a verification environment having a hardware development language interface. The verification process also comprises a device under test having a hardware development language interface operable to communicate with the verification environment hardware development language interface, and also having an Infiniband interface. The verification process additionally comprises a remote Infiniband link having an Infiniband interface operable to communicate with the device under test Infiniband interface and also having a socket protocol interface operable to communicate with a further verification process.

Abstract: A novel N×N Crossbar Packet Switch is disclosed, which crossbar switch is based on a distributed port architecture, asynchronous output port arbitration, support of non fixed-size packets (cells), support for virtual channels (VC) and/or priority, and which only requires 2*N*N control lines for the arbitration.