Patent ID: 6765873
Filing Date: 2004-07-20
Classification: H04L,H04Q

Abstract:
A connection bandwidth management process for use in a high speed packet switching network having a plurality of switching nodes interconnected through a plurality of communication links, each of the switching nodes having means for switching packets from at least one input link to at least one output link, each of the output links being coupled to at least one buffer in the switching node for queuing packets before they are transmitted over the output link, each of the communication links supporting the traffic of a plurality of user connections statistically multiplexed over the link, each user connection being allocated an initial agreed-upon bandwidth through the network, with each of the communication links being possible oversubscribed, the connection bandwidth management process comprising the steps of:periodically receiving, in a network monitoring center, link monitoring data on the communication links, and storing the link monitoring data in a computer memory in the network monitoring center; selecting one monitored link and retrieving the corresponding link monitoring data from the computer memory; analyzing the link monitoring data for the selected link wherein the link monitoring data includes, for each of the monitored links, a time distribution of the occupancy of the buffer measured during a predetermined monitoring time period; determining whether the selected link is oversubscribed or not; upon determining that the selected link is oversubscribed that the link monitoring data for the selected link satisfies at least one predetermined condition, reallocating the bandwidth initially allocated to each of the connections boarded on the selected link, such that the sum of the reallocated bandwidth of the connections boarded on the selected link is less or equal to the total bandwidth capacity of the selected link; and obtaining the time distribution of the occupancy of the buffer by: defining a plurality N, with N being an integer, of buffer occupancy thresholds T(1) to T(N), each of the thresholds being indicative of a ratio of the total occupancy of the buffer; defining a plurality N of buffer states ST(1) to ST(N), each of the states being indicative of the amount of packets stored in the buffer at a given instant in relation to the thresholds T(1) to T(N); defining a plurality N of counters, PT(1) to PT(N), each of which, PT(i) with i being an integer comprised between 1 and N, being incremented when the buffer state is determined to be at any of the states ST(i) to ST(N), whereby the measurement of the time distribution of the occupancy of the at least one buffer during a predetermined monitoring time period is achieved by obtaining a set of N values PT(1) to PT(N) indicating respectively the percentage of packets that have armed during the monitoring period while the amount of packets stored in the buffer at the packet arrival instant was equal or greater than threshold T(1) to T(N), respectively.