1 Introduction
Megaco/H.248 is a protocol for control of elements in a physically decomposed multimedia gateway, enabling separation of call control from media conversion. A Media Gateway Controller (MGC) controls one or more Media Gateways (MG).
This version of the stack supports both version 1 and version 2 as defined by:
- version 1 - RFC 3525 & H.248-IG (v10-v13)
- version 2 - draft-ietf-megaco-h248v2-04 & H.248-IG (v10-v13)
The semantics of the protocol has jointly been defined by two standardization bodies:
- IETF - which calls the protocol Megaco
- ITU - which calls the protocol H.248
1.1 Scope and Purpose
This manual describes the Megaco appliacation, as a component of the Erlang/Open Telecom Platform development environment. It is assumed that the reader is familiar with the Erlang Development Environment, which is described in a separate User's Guide.
1.2 Prerequisites
The following prerequisites is required for understanding the material in the Megaco User's Guide:
- the basics of the Megaco/H.248 protocol
- the basics of the Abstract Syntax Notation One (ASN.1)
- familiarity with the Erlang system and Erlang programming
The application requires Erlang/OTP release R7B or later.
1.3 About This Manual
In addition to this introductory chapter, the Megaco User's Guide contains the following chapters:
- Chapter 2: "Architecture" describes the architecture and typical usage of the application.
- Chapter 3: "Internal form and its encodings" describes the internal form of Megaco/H.248 messages and its various encodings.
- Chapter 4: "Transport mechanisms" describes how different mechanisms can be used to transport the Megaco/H.248 messages.
- Chapter 5: "Debugging" describes tracing and debugging.
1.4 Where to Find More Information
Refer to the following documentation for more information about Megaco/H.248 and about the Erlang/OTP development system:
- version 1, RFC 3525
- old version 1, RFC 3015
- Implementors Guide version 10-13
- version 2, draft-ietf-megaco-h248v2-04
- the ASN.1 User's Guide
- the Reference Manual
- Concurrent Programming in Erlang, 2nd Edition (1996), Prentice-Hall, ISBN 0-13-508301-X.