ITU-T G.799.4 PDF

De-jitter buffers have a major effect on voice and data transmission quality in telecommunication networks. They affect the three service categories of public switched telephone network/integrated service digital network (PSTN/ISDN) voice, voiceband data (due to PSTN modem calls) and ISDN circuit mode data. Since the requirements for the settings of de-jitter buffers differ for different services, this Recommendation describes the activation and mode switching procedures of de-jitter buffers, including the requirement for in-band tone activating and other control mechanisms.

It is assumed that the clock accuracy of all elements involved is sufficiently high for application of this Recommendation.

This Recommendation covers de-jitter buffer usage in circuit-to-IP media gateways, such as residential, access or trunking gateways in the context of the next generation network/internet protocol multimedia subsystem (NGN/IMS).

The notion of circuit relates to a PSTN analogue line or an ISDN 1×64 bearer channel.