Hola

Contestando a la duda sobre si en DOCSIS el transporte es mediante tramas MPEG-2, os copio un párrafo sacado de la especificación de capa MAC de DOCSIS 3.1 (la última versión) que tenéis [aquí]:

"Downstream Convergence Layer: For OFDM downstream channels, DOCSIS 3.1 no longer uses MPEG-2 as the convergence layer between the MAC and the PHY as was the case in DOCSIS 3.0. In DOCSIS 3.1, the MAC frames are simply encoded in FEC codewords and transmitted by the PHY. DOCSIS 3.1 also introduces the concept of a PHY Link Channel (PLC), which is a signaling sub-channel with information to acquire and maintain lock on downstream OFDM signal. There is also the new concept of a Next Codeword Pointer (NCP), where the CMTS tells the modems which codewords to decode [DOCSIS PHYv3.1].". Cable Television Laboratories, "Data-Over-Cable Service Interface Specifications. DOCSIS 3.1. MAC and Upper Layer Protocols Internface Specification", pag.51

Así que hasta DOCSIS 3.0 sí era así y ahora ya no. Tendré que actualizar las transparencias :-)