Method and a device for adapting error protection in a communication network, and a method and device for detecting between two states of a communication network corresponding to different losses of data

A device for adapting error protection in a communication network, comprising:

• means for determining periods of time that are homogeneous as regards the distribution law of losses over the network,
• means for classifying the homogeneous periods of time into at least two classes, on the basis of information representing losses over the network and/or representing a corresponding level of protection, during these periods of time,
• means for selecting a protection strategy on the basis of said classes;
• and
• means for determining a probability of alternation between two of said classes, and wherein the means for selecting is operable to select the protection strategy on the basis of said probability of alternation.

A method of detecting transition between two states of a communication network corresponding to different loss rates of sent data, the method comprising:

• a step of determining a probability of transition;
• and
• a step of determining the existence of a transition on the basis of said probability,
• wherein, the communication network conveys data packets and the step of determining a probability of transition comprises:
• a step of detecting lost packets from among the data packets sent;
• a step of determining distances representing separations between the sequence numbers of said lost packets, and
• a step of calculating probability of transition between a first set of distances and a second set of distances chosen from among the determined distances.

A device for detecting transition between two states of a communication network corresponding to different loss rates of sent data, comprising:

• a means for determining a probability of transition;
• and
• a means for determining the existence of a transition on the basis of said probability,
• wherein, the communication network conveys data packets and the means for determining a probability of transition is operable to determine the probability by:
• detecting lost packets from among the data packets sent;
• determining distances representing separations between the sequence numbers of said lost packets, and
• calculating probability of transition between a first set of distances and a second set of distances chosen from among the determined distances.