Patent ID: 8687507

Claim:
A method of estimating a condition in a data path of a communication network, comprising: providing and transmitting, in a probe node, a first set of probe packets to a destination node during real-time operation of the data path, the first set of probe packets having a first inter-packet separation (IPSsent) and a time-to-live (TTL); receiving a second set of packets at the probe node generated in an intermediate node when the time-to-live (TTL) for the first set of probe packets expires, the second set of packets having a second inter-packet separation (IPSreceived) and being of a decreased size by comparison with the first set of probe packets; providing, in response to traversal of the data path by the first set of probe packets, estimation data for use in estimating the condition; and producing an estimation of the condition, wherein said estimation of the condition is calculated based on a difference between the first inter-packet separation and the second inter-packet separation.