Embodiments of the invention enable
minimum latency site independent real-time video transport over
packet switched networks. Some examples of real-time video transport are video conferencing and real-time or
live video streaming. In one embodiment of the invention, a network node transmits live or real-
tine audio and video signals, encapsulated as
Internet Protocol (IP) data packets, to one or more nodes on
the Internet or other IP network. One embodiment of the invention enables a user to move to different nodes or move nodes to different locations thereby providing site independence. Site independence is achieved by measuring and accounting for the
jitter and
delay between a
transmitter and
receiver based on the particular path between the
transmitter and
receiver independent of
site location. The
transmitter inserts timestamps and sequence numbers into packets and then transmits them. A
receiver uses these timestamps to recover the transmitter's
clock. The receiver stores the packets in a buffer that orders them by sequence number. The packets stay in the buffer for a fixed latency to compensate for possible network
jitter and / or packet reordering. The combination of
timestamp packet-
processing, remote
clock recovery and synchronization, fixed-latency receiver buffering, and error correction mechanisms help to preserve the quality of the received video, despite the significant network impairments generally encountered throughout
the Internet and
wireless networks.