An open standard for audio over IP which is designed to allow other audio over IP systems to interoperate. It defines most aspects of audio over IP with the exception of advertisement and discovery.

Areas defined include: Synchronization using PTP (IEEE 1588), Sample frequencies (44.1, 48 or 96 kHz), bit depth of 16 or 24 bits, Network layer = IPv4, QoS using DiffServ – Audio = Assured Forwarding AF41 (DSCP 34), Clock = Expedited Forwarding EF (DSCP 46), RTP over UDP – unicast and multicast, length of the audio packet, maximum number of streams, the size of the receive buffer, the use of Session Description Protocol (SDP) and the use of Session Initiation Protocol (SIP) for unicast connections and IGMP for multicast connections