Time-sensitive multimedia endpoint interface bridging through ethernet transport

Abstract

An Ethernet bridge architecture enables timing replication. The Ethernet bridge receives data packets from a sensor (such as a video sensor) and immediately tags each data packet with a transmitter timecode. The tagged data packets are then forwarded to the appropriate receiver over the digital data network or link that may exhibit packet delivery time variations and reordering. The receiver identifies data packets including the local timecode and delays processing (display) of the data packet until a timecode local to the receiving node matches the transmitter timecode plus some delay. The receiver also restores the original order of the packets by observing packet sequence number and placing them at appropriate location in memory buffer. By delaying processing, the Ethernet bridge compensates for any variance in network latency. The delay should be greater than a worst-case delay as defined by the network architecture. The Ethernet bridge allows a distributed multi-camera and multi-display system based on high-bandwidth Ethernet infrastructure, while still using non-Ethernet sensors, displays, and application processors.