Systems and methods for path record handling in a fabric without host stack cooperation in a high performance computing environment. In a case where the subnet manager has determined “homogenous subnet/fabric” or “semi-homogenous subnet/fabric” status for the current topology, but is still receiving path queries, the subnet manager can use the relevant status to avoid any route evaluation and generate path record either only based on the configuration status of the requesting port in the homogenous case, or by comparing the configuration status of both ports in the semi-homogenous case.

Systems and methods for path record handling in a fabric without host stack cooperation in a high performance computing environment. In a case where the subnet manager has determined homogenous subnet/fabric or semi-homogenous subnet/fabric status for the current topology, but is still receiving path queries, the subnet manager can use the relevant status to avoid any route evaluation and generate path record either only based on the configuration status of the requesting port in the homogenous case, or by comparing the configuration status of both ports in the semi-homogenous case.

Systems and methods for path record handling in a fabric without host stack cooperation in a high performance computing environment. In a case where the subnet manager has determined homogenous subnet/fabric or semi-homogenous subnet/fabric status for the current topology, but is still receiving path queries, the subnet manager can use the relevant status to avoid any route evaluation and generate path record either only based on the configuration status of the requesting port in the homogenous case, or by comparing the configuration status of both ports in the semi-homogenous case.

Systems and methods for path record handling in a fabric without host stack cooperation in a high performance computing environment. In a case where the subnet manager has determined homogenous subnet/fabric or semi-homogenous subnet/fabric status for the current topology, but is still receiving path queries, the subnet manager can use the relevant status to avoid any route evaluation and generate path record either only based on the configuration status of the requesting port in the homogenous case, or by comparing the configuration status of both ports in the semi-homogenous case.

A network element (101), for example a router, comprises a processing system (103) for running a protocol in accordance of which the network element is communicating with another network element. The protocol comprises monitoring whether the protocol receives, within a protocol message -specific time-window, a protocol message transmitted by the other network element. The time-window may represent for example a timeout period. The processing system measures waiting times of messages received at the network element, where each measured waiting time is at least a part of time a corresponding received message waits for a service provided by the processing system. The processing system determines the length of the time-window based on the measured waiting times. Therefore, the waiting time of the received protocol message can be compensated for and thereby wrong determinations about the reachability of the other network element can be avoided or at least reduced.

A lookup system includes a ternary content-addressable memory TCAM configured to carry out a lookup on the basis of a lookup key so as to produce a preliminary lookup result. The lookup system further includes a subsystem configured to produce a final lookup result on the basis of the preliminary lookup result and auxiliary data including at least a part of bit values of do-not-care bit positions of the lookup key such that the preliminary lookup result is independent of the bit values of the do-not-care bit positions. The required number of TCAM-lines can be reduced because different alternatives of the auxiliary data corresponding to different possible bit values of the do-not-care bit positions of the lookup key are handled with the subsystem instead of the TCAM.