Method and arrangement for congestion control in packet networks

A medium readable by means of a computer and having a computer readable program code embodied therein, comprising:

• said computer at least partly being an arrangement for controlling congestion of a network node capacity shares used by a set of data flows in a communications network,
• said data flows including non-terminated data flows having specific characteristics,
• said arrangement further comprising a classifier arrangement, a load meter, first and second lists, first, second and third selectors, a queue arrangement and a scheduler,
• wherein said program code is provided for causing said arrangement to assume:
• a first phase in which the first selector selects flow identities from the queue and saves them in the first list,
• a second phase, in which the load meter detects congestion or congestion anticipation and starts the second and/or third selectors if they have not been started, no new flows are and saves them in a second list, said third selector selects flow identities from the lists and modifies said specific characteristic in form of service level of the respective flows, such that the flows are removed from the current priority level/pipe,
• a third phase, in which after the queue load falls below a congestion/congestion anticipation level but not below a new flow admission level the load meter stops first and/or second selectors, and
• a fourth phase, in which the load meter detects load of the queue being under the new flow admission threshold and instructs said third to restore service level of the service level modified flows in an ordered or random way.

A computer data signal embodied in a carrier wave, said computer signal comprising:

• a computer readable program code readable by means of a computer, the computer at least partly being realized as an arrangement for controlling congestion of a network node capacity shares used by a set of data flows in a communications network, said data flows including non-terminated data flows having specific characteristics,
• said arrangement mainly comprising a classifier arrangement, a load meter, first and second lists, first, second and third selectors, a queue arrangement and a scheduler,
• wherein said program code is configured to cause said arrangement to assume:
• a first phase in which the first selector selects flow identities from the queue and saves them in the first list,
• a second phase, in which the load meter detects congestion or congestion anticipation and starts the second and/or third selectors if they have not been started, no new flows are allowed on the queue/pipe, said second selector selects flow identities from the queue and saves them in a second list, said third selector selects flow identities from the lists and modifies said specific characteristic in form of service level of the respective flows, such that the flows are removed from the current priority level/pipe,
• a third phase, in which after the queue load falls below a congestion/congestion anticipation level but not below a new flow admission level the load meter stops first and/or second selectors, and admission threshold and instructs said third to restore service level of the service level modified flows in an ordered or random way.