Protocol for monitoring communication traffic

A communication system comprising:

• network probes and a plurality of routers,
• a first network probe among said network probes being associated with a first router of said plurality of routers and with a first end-point of the first router, a second network probe among said network probes being associated with a second router of said plurality of routers and with a second end-point of the first router, the communication system comprising electronic circuitry configured to carry out, within the context of monitoring traffic in a communication tunnel between the first end-point and the second end-point:
• periodically injecting, by the first probe, flag packets in parallel to the traffic of the communication tunnel, each flag packet including timestamp information expressing a time reference of injection of said flag packet;
• gathering information, by one of the first network probe or the second network probe, relating to a variation in the traffic timing in the communication tunnel, the timing variation being measured due to a difference between the timestamp information contained in the flag packets and timestamp information relating to an instant at which said flag packets were captured by the second probe, wherein at least the second network probe comprises at least one measurement table for storing a sampling log of flag packets captured by the second network probe;
• transmitting, by the first probe, a request to the second probe, the request involving a range of sequence numbers to be considered and requesting to transmit in response information derived from computations of said sampling log using the range of sequence numbers, or to transmit in response all or some of said sampling log which corresponds to said range of sequence numbers so that the first probe performs the computations of said sampling log using the range of sequence numbers and obtains the information derived from the computations;
• and
• assessing, using the information derived from the computations, possible congestion situations experienced by the communication tunnel as a function of said gathered information.