Communication of active data flows between a transport modem termination system and cable transport modems

Multiplexing of information from a plurality of information flows into fixed-length packets such as, but not limited to, MPEG packets allows efficient utilization of bandwidth and also can be used to reduce transmission latency. In addition, utilizing MPEG packets and transport streams for octet multiplexing allows the packets carrying octet-multiplexed data to easily be integrated with other MPEG packets for other services that are commonly found in cable transmission networks of all coax, hybrid fiber coax, and/or all fiber. The multiplexing/demultiplexing of octets using MPEG packets generally is described by mappings that specify the use of octets in MPEG packets. Changes to allocations in a map generally should be propagated in a way that reliably ensures that both the transmitter and receiver have a consistent view of the octet mappings.