Patent ID: 7443804
Filing Date: 2008-10-28
Classification: H04L

Abstract:
1. A method of estimating available bandwidth of a packet network comprising the steps of: determining the inter-packet intervals in a received train of packets that were injected into the network with known inter-packet intervals; determining a variance of a distribution of sojourn times through the network of the packets in the received train of packets from the determined inter-packet intervals and the known inter-packet intervals; and estimating the available bandwidth of the packet network from the determined variance; wherein the step of determining a variance of a distribution of sojourn times comprises: a) determining for each packet j in the received train of N packets the difference of sojourn times for packet j against all other packets in the received train by calculating the sum over each packet k of the difference between the inter-packet interval between packets j and k and the known inter-packet interval between packets j and k in the train of packets injected into the network; b) determining the deviation of the sojourn time for each packet j from the mean sojourn time of the packets in the train by dividing the sum calculated in step a) for each packet j by N; and c) determining the variance of the distribution of sojourn times of all the packets in the received train by calculating the average over N of the sum of the squares of the deviations determined in step b) of each packet j.