Thursday, September 06, 2007

AMQP in 10 mins : Part1 - Introduction

Advanced Message Queing Protocol is a an open standard with royalty free use. It has a strong focus on the financial services industry and provides the performance and reliability required by the said industry.

AMQP Working Group
The AMQP working group is responsible for defining and maintaining the sepcification. The website www.amqp.org provides details on licensing, FAQ, JIRA and a list contributors and a download page.

Version Numbering
The AMQP Version Numbering scheme consists of a major and minor revision number. Ex: 0-10.
Major versions > 0 will provide backward compatibility between minor versions. The current version of the protocol is 0-9. The AMQP WG is expected to release the 0-10 version shortly. Currently the specification is in a rapid growth stage.

Interoperability
AMQP provides complete interoperability via
  • A network wire-level protocol
  • A defined set of messaging capabilities a.k.a AMQP model
One can partially imply the semantics from the wire-protocol. However we need to define the semantics explicitly in order to guarantee exact behaviour in each broker implementation.

Reliability
The 0-10 (in-progress) version has provided functionality to ensure Guaranteed Delivery to satisfy the level of reliability required by the financial services industry. I will cover this topic in detail in a future blog post as part of the AMQP in 10 mins series.

Full Transaction Support
The 0-10 spec also provides protocol level functionality for distributed transactions. This topic will also be covered in detail in a future blog post.

Security
Security is the main focus for 0-11 version of the protocol. Currently there is only rudimentary support provided via TLS. Planned features include but not limited to partial encryption and payload signing.

Known Implementations
AMQP is platform agnostic and language neutral. Currently we have implementations from a wide variety of languages from procedural to object oriented to functional.

The Apache Qpid project has broker implementations in java and c++ and client implementations in java, c++, python, ruby and .NET.

RabbitMQ provides a broker implementation in Erlang and a client implementation in java

Open AMQ provides broker and client implementations in C.

What about JMS?
JMS can be implemented on top of AMQP. The AMQP WG is also working on standardising the AMQP-JMS mapping and is scoped for 0-11 version of the protocol. This will enable two different JMS over AMQP implementations to behave exactly the same way.
The Apache Qpid project provides an implementation of JMS over AMQP.

Next Part : Part2 - Achieving Interoperability And Avoiding Vendor Lock-in

Prev Part : Part0

No comments: