scope:

This document provides requirements for advanced bonding of multiple digital subscriber lines (DSL) to transport ATM streams. The specifications of this standard provide a complete description of startup, operational, and contingency modes of operation, which allows for interoperability between vendors.

This document includes the following types of requirements, recommendations, and information for defined DSL systems, including:

♦ Higher-layer transport-independent requirements; and

♦ Higher-layer transport-dependent -- e.g., ATM -- requirements.

Purpose

The purpose of this standard is to assist manufacturers, providers, and users of products on how to use multiple DSL lines to carry a single ATM payload stream. In order to satisfy this purpose, requirements and guidelines are provided. When the requirements contained in this standard are satisfied, the bonding system is standard compliant. The standard is written to satisfy the following bonding objectives:

1. Bonding shall support dynamic removal and restoration of pairs without human intervention.

2. Bonding shall support disparate data rates, up to a ratio of 4-to-1 (fastest to slowest), amongst its pairs.

3. The protocol shall allow bonding of 2-32 pairs.

4. The protocol shall permit bonding of randomly assigned ports on an access node.

5. The protocol shall be PHY independent.

6. The protocol shall incur a maximum overall one-way bonding delay of 2 ms.

In order for implementations compliant to this standard to be interoperable between vendors, an initialization procedure, a payload tagging method, and OAM capability are provided. The specification begins with a list of normative references followed by a list of definitions and acronyms.