Data processing

A method of processing data in a telecommunications network, the telecommunications network comprising at least a network node and a user device, the user device comprising a primary jitter buffer having a constant packet play-out rate and a secondary jitter buffer located upstream of the primary jitter buffer in the user device, the method comprising, at the user device:

• receiving incoming packets destined for the primary jitter buffer;
• passing the received packets through the secondary jitter buffer downstream towards the primary jitter buffer;
• at least on the basis of one or more known characteristics of the primary jitter buffer, maintaining an estimate of a current state of the primary jitter buffer;
• disabling the secondary jitter buffer until such time that the maintained estimate indicates that the primary jitter buffer is operating at a capacity other than a given nominal capacity, wherein the maintaining of the estimate of a current state of the primary jitter buffer comprises maintaining a gauge estimating how full the primary jitter buffer is;
• decrementing the gauge at the constant packet play-out rate of the primary jitter buffer;
• and
• incrementing the gauge when a given packet is passed downstream towards the primary jitter buffer by the difference between a timestamp of the given packet and a timestamp of the previous packet passed downstream towards the primary jitter buffer.

A user device configured to process data in a telecommunications network, the telecommunications network comprising at least a network node and a user device, the user device comprising a primary jitter buffer having a constant packet play-out rate and a secondary jitter buffer located upstream of the primary jitter buffer in the user device, the user device being configured to:

• receive incoming packets destined for the primary jitter buffer;
• pass the received packets through the secondary jitter buffer downstream towards the primary jitter buffer;
• at least on the basis of one or more known characteristics of the primary jitter buffer, maintain an estimate of a current state of the primary jitter buffer;
• and
• disable the secondary jitter buffer until such time that the maintained estimate indicates that the primary jitter buffer is operating at a capacity other than a given nominal capacity, wherein, in response to the maintained estimate indicating that the primary jitter buffer is operating at an empty capacity, the method comprises:
• temporarily suspending passing of packets downstream towards the primary jitter buffer at the constant packet play-out rate;
• storing incoming packets destined to be passed towards the primary jitter buffer, wherein the secondary jitter buffer has an initial capacity larger than the given nominal capacity of the primary jitter buffer;
• once the initial capacity of the secondary jitter buffer is reached, passing a burst of packets downstream towards the primary jitter buffer, the burst of packets being sufficient to return the operation of the primary jitter buffer to the given nominal capacity;
• and
• resuming passing of packets downstream towards the primary jitter buffer at the constant packet play-out rate.