ANSI SCTE 136-2 pdf free download

ANSI SCTE 136-2 pdf free download.Cable Modem TDM Emulation Interface Standard.
This section describes the principle technologies and operational considerations germane to the development of a T1/E 1-bearing TE-CM and its use. Major sub-topics include: Clocking – T1/E1 transport technology is synchronous in nature; requiring accurate and stable clocking. Since T1 transport requires that T1 signals are handed from one service provider to another, each service provider must adhere to the same clocking requirements. Further, these synchronous clocking requirements must be very stringent to ensure reliable operation. The section on clocking (Section 5.5.1) will further describe these requirements largely based on existing ITU and ATIS requirements. Data Protocol 1. Voice protocol – Phone calls at termination are completely analog, carrying linear voice signals over dedicated wires. It wasn’t long before the phone companies realized that a wire could carry more than one phone call if the calls were time-multiplexed on the wire. Calls are now time sampled, and the resulting digital signals are time-multiplexed over wires in T1/E 1 formats (among others). 2. Data protocol – It did not take long for engineers to realize that T1/E 1 transport could be used for standard data (not just voice). T1 signals are now used to transport digital data in many different data formats which are beyond the scope of this spec. This standard accommodates the transport of either voice or data by specifying more than one data format for the IP packets that carry the T1 information over DOCSIS channels. The sections below addressing ‘structure agnostic’ protocol are germane to data transport. Most of this standard addresses T1 transport of voice calls, but the standard accommodates data transport as well. 3. Signaling data protocol – To successfully combine several voice phone calls into a T1 structure, data describing the state of each call must be included. Such call state data may include the progress of the call and the health of the transport network carrying the call. Several existing standards describe this sign
An Embedded TDM Emulation Adaptor (eTEA) is an eSAFE device as specified by [eDOCSIS]. An eTEA is embedded in a TE-CM.
An eTEA has a Ti, El, or ii interface connector and contains the following elements/interfaces:
• L2 Ethernet – This is the Layer 2 Ethernet element where IP Pseudo Wires are transceived.
• Pseudo Wires (PW1, PW2, …, PWN) – Pseudo Wires are logical IP packet flows that contain encapsulated TDM traffic. Pseudo Wires are terminated and generated by IWF.
• Interworking Function (IWF) – The Interworking function consists of a TSP data interface on one side, an IP Packet interface on the other side, and the functionalities to encapsulate TDM data into a Pseudo wire in one direction and extract TDM data from Pseudo Wire in the other direction. Encapsulation and transmission may involve clocking from the CU.
• TDM Service Flows (TS 1, TS2, …, TSN) – TDM data associated with a Pseudo Wire and TDM interface. The TDM Service Flows may be multiplexed onto one or more TDM interfaces through the TDM Service Processor.
• TDM Service Processor – The TDM Service Processor connects and may multiple TDM Service Flows onto one or more TDM interfaces.
• Ethernet Interface. This Customer facing Ethernet interface has the following uses:
• To launch the optional 1588 local master timing function on the customer Ethernet network per Section
6.4.5:
• For DOCSIS testing of an eCM;
• For testing of clock recovery per Section 6.4.7.1;
• For (out of scope) use to carry TDM data per Section 5.3.1.
ANSI SCTE 136-2  pdf download.