a method for measuring latency in a bi - directional ring network includes transmitting a latency measurement packet from an originating node to a peer node and noting a time of receipt of the packet at the peer node . the packet is then transmitted back to the originating node in the opposite direction , while recording in the packet an indication of a peer node difference between a time of transmission of the packet from the peer node to the originating node and the time of receipt of the packet at the peer node . a time of return of the packet to the originating node is noted , so as to determine an originating node difference between a time of transmission of the packet from the originating node to the peer node and the time of return of the packet to the originating node . the latency is calculated by taking a difference between the originating node difference and the peer node difference .