ANSI SCTE-139-2007 pdf download Edge Resource Manager Interface for Modular Cable Modem Termination Systems
5 TECHNICAL OVERVIEW
5.1 Registration Interface
The registration interface (ERMI–1) allows EQAMs to register their QAM channel resources with an ERM.
5.1.1 Goals, Scope and Constraints
The Registration interface was designed to meet the following goals:
• Enable EQAMs to register their resources with an ERM
• Help the ERM to detect when failures occur in resources that it manages
The protocol used on this interface is based on TRIP [RFC 3219]. TRIP was designed to assist networks to locate voice-over-IP gateways and to route voice-over-IP traffic to an appropriate egress gateway. TRIP is a policy-driven protocol for advertising the reachability of telephony destinations between location servers, and for advertising attributes of the routes to those destinations.
Some EQAM resource registration protocols used in VOD systems are based on TRIP. Using a similar protocol to implement DOCSIS downstream resource allocation simplifies EQAM design. When a VOD application needs a downstream QAM channel resource, it will request a downstream QAM channel resource from the ERM. When a DOCSIS application needs a downstream QAM channel resource, it will request a downstream QAM channel resource from the ERM.
5.1.1.1 Registering QAM Channels Each ERM is responsible for managing the resources of one or more EQAMs. In order for an ERM to manage an EQAM’s resources, it must first obtain an inventory of the resources associated with that EQAM. It must also obtain IP and/or RF addressing information associated with the EQAM and those resources in order to determine how to communicate with them. For example, an EQAM contains one or more QAM channels, each of which has associated RF properties (for example, the carrier frequency) and an RF address (the MPEG-2 Transport Stream ID (TSID)).
In order to allocate a particular QAM channel to a DOCSIS MAC domain, an ERM must know the following properties associated with that QAM channel:
• TSID
• QAM configuration, Capability, and QAM grouping
• Service Group
• Total available bandwidth