An MPEG packet is 188 bytes in size, and usually seven MPEG packets are contained in one IP packet. Therefore, if one IP packet is lost, this usually entails the loss of seven MPEG packets. Since packet loss is detrimental to IPTV quality, it should be closely monitored.
Lost MPEG packets are equivalent to Continuity Count (CC) errors. Each MPEG transport stream packet contains a 4-bit counter which continuously increments from 0 to 15, wrapping around to zero on reaching the maximum value. The purpose of the counter is to enable recognition of missing or repeated transport stream packets, thus drawing attention to any multiplexer or IP network problems.