Erroneous MPEG packet synchronization in the MCNS/SCTE/ITU-T J.83 Annex B standard

This paper presents a phenomenon with repeating data packets sent according to the MCNS (multimedia cable network system) DOCSIS (data over cable service interface specification)/SCTE (Society of Cable Telecommunication Engineers)/ITU-T 5.83 Annex B standard. When repeating packets are received by a receiver, the receiver may erroneously lock onto the bit stream and produces incorrect MPEG packets. Repeating packets are usually not generated in practical systems. They are, however, easy to generate and preferred in a testing environment during product development. A system vendor may unknowingly encounter this phenomenon and incur delays in product designs in trying to solve this apparent error. This paper presents the mathematical background on the cause of this phenomenon.