Perfect stream in relation to VQM

Perfect stream uses two identical multicast streams traversing two diverse network paths to construct a multicast stream that is less susceptible to network faults. VQM can be configured in conjunction with perfect stream, which allows VQM to monitor the two ingress as well as the egress streams. By using the VQM statistics from all three streams, the operator can assess the quality of the network transporting the multicast stream, the performance of perfect stream, and the viewing quality for the end user. VQM and Perfect Stream can be enabled on the same video-group (the same ISA).