Access@ Terminals@ Transmission and Multiplexing (ATTM); Integrated Broadband Cable and Television Networks; IPCablecom 1.5; Part 14: Embedded MTA Analog Interface and Powering Specification (V1.1.1)
The present document defines the embedded MTA (E-MTA) requirements for the analog interface and for powering of the E-MTA. An embedded MTA is a DOCSIS cable modem (CM) integrated with an IPCablecom multimedia terminal adapter (MTA). The purpose of the present document is to define a set of requirements that will enable a service that is sufficiently reliable to meet an assumed consumer expectation of essentially constant availability@ including@ specifically@ availability during power failure at the customer's premises@ and (assuming the service is used to connect to the PSTN)@ access to emergency services (911@ etc.). The present document covers requirements for the E-MTA analog interface and for powering of the E-MTA. It is the intention of the present document to address requirements only for the E-MTA. See clause 5.3.1 for a complete description of the E-MTA. To enable a service that meets the assumed customer expectations described in clause 1.1@ three E-MTA interfaces have been identified: 1) powering the E-MTA; 2) telemetry support; and 3) the analog POTS interface. Powering the E-MTA is critical for the service to function during periods when utility power fails. Consequently@ the power consumption characteristics of the E-MTA will enable service providers to offer alternate powering techniques. Telemetry support enables the service provider to remotely monitor the status of the E-MTA. The first application of telemetry enables remote monitoring of the E-MTA power source. The analog POTS interface requirements ensure that CPE that meets telephone industry interoperability requirements (normal telephones@ answering machines@ etc.) will also operate in the IPCablecom environment. NOTE 1: The voice-grade analog transmission requirements are dependent on the compression algorithm utilized to transport the packetized voice signal in the IPCablecom architecture. These requirements are derived from existing PSTN requirements that are based on a full 64 kbps voice channel. Therefore@ the requirements specified are relevant only for the G.711 audio codec. Other audio codec compression algorithms specified by IPCablecom [2] are not addressed in the present document. NOTE 2: The telemetry interface specified in the present document is between the E-MTA and an external local un-interruptible power supply (UPS). The UPS itself is not within the scope of the present document@ so specific requirements for the UPS are not included here. Nonetheless@ requirements for the E-MTA telemetry interface may have certain design implications on the UPS.