Patent ID: 8107388
Filing Date: 2012-01-31
Classification: H04L

Abstract:
1. A method for a Voice-over-Internet-Protocol telephony communication manager to detect type-of-service remarking in a network, the method comprising: transmitting, by a first element to a second element in the network, a plurality of route-tracing messages, wherein each route-tracing message comprises (i) a designated type-of-service value and (ii) a time-to-live value, and wherein the time-to-live value monotonically increases with each successive route-tracing message; receiving, by the first element, a plurality of time-exceeded messages, wherein each time-exceeded message comprises a type-of-service value that is associated with an element in the network that received at least one of the route-tracing messages; calculating, by the first element, a path from the first element to the second element, wherein the path comprises the elements in the network from which the first element received at least one time-exceeded message; and identifying, by the first element, a third element that is in the path between the first element and the second element and is associated with a type-of-service value that is different than the designated type-of-service value; wherein the network comprises the first element, the second element, and the third element, and wherein the first element is the Voice-over-Internet-Protocol telephony communication manager that operates in the network, and wherein the Voice-over-Internet-Protocol telephony communication manager periodically and automatically repeats the transmitting, receiving, calculating, and identifying operations for each of a plurality of different paths in the network, enabling the Voice-over-Internet-Protocol telephony communication manager to detect type-of-service remarking by elements in the network.