Patent ID: 7796524

Claim:
A method of monitoring quality of service in telephony communications over a packet-based network between two points, at least one of which is an endpoint, wherein said endpoint is a telephony device having an interface which is accessible to a user to enable said user to participate in a telephony session over the network; said telephony device further having an output for presenting information to said user; the method comprising the steps of: transmitting test packets across the network while a telephony session including said telephony device is in progress and monitoring transmission characteristics of said test packets, said test packets including a first series of test packets which issue from a source location to a destination location and a second series of test packets which issue from said destination location to said source location in response to said first series of test packets; dynamically calculating from said transmission characteristics a measure of network performance comprising a measure of packet loss by comparing the packets issued from the source location and the packets received back at the source location, using the measure of packet loss and the identity of the communications codec being employed by the endpoint to calculate an equipment impairment factor (Ie); and providing at said output of said telephony device a dynamic indication of said equipment impairment factor (Ie) during said telephony session.