CONGESTION HANDLING IN A PACKET SWITCHED NETWORK DOMAIN

摘要

A system a core (104), an edge node (102, 103) and a method are provided for congestion handling in a packet switched network domain. In case of congestion overload is measured, the data packets in proportion to the overload are marked and the signaled overload is stored. At least one egress node (103) receives marked and not marked packets, decodes and counts the overload from the marked packets in a counting interval. Congestion report messages are sent to ingress nodes (102) where flows are terminated. A core node (104) comprises a storage means (314) taking into account the previously signaled overload, which are already being handled in a congestion handling control loop. An edge node (103) comprises means for adding new flows to the set of affected flows, means for identifying affected flows to be terminated so that the number of identified affected flows should generate together traffic equal to the overload, and means for removing flows to be terminated from set of affected flows. In an advantageous embodiment the market module (315) applies a hysteresis algorithm with a higher bound used to detect congestion and to trigger the marking of user data packets in proportion to the measured overload, and a lower bound used as the reference to measure the overload ratio.