What does 0-9-1 stand for in AMQP 0-9-1 protocol

Question

I couldnt find the exact logic behind 0-9-1 in the AMQP 0-9-1 protocol. Please someone explain it.

Answer 1

The complete specification is here:

• http://www.amqp.org/specification/0-9-1/amqp-org-download

"0-9-1" simply happens to be the version#:

AMQP
Advanced Message Queuing Protocol
Protocol Specification
Version 0-9-1, 13 November 2008
A General-Purpose Messaging Standard

1.4.2 Version Numbering

The AMQP version is expressed using two or three digits – the major number, the minor number and an optional revision number. By convention, the version is expressed as major-minor[-revision] or major.minor[.revision]:

• The major, minor, and revision numbers can take any value from 0 to 99 for official specifications.
• Major, minor, and revision numbers of 100 and above are reserved for internal testing and development purposes.
• Version numbers indicate syntactic and semantic interoperability.
• Version 0-9-1 is represented as major = 0, minor = 9, revision = 1.
• Version 1.1 would be represented as major = 1, minor = 1, revision = 0. Writing “AMQP/1.1” is equivalent to writing “AMQP/1.1.0” or AMQP/1-1-0.

Answer 2

It is the version 0.9.1.

<amqp major="0" minor="9" revision="1" port="5672" comment="AMQ Protocol version 0-9-1">