Introduction

Federation Concepts

Inter-Broker Links

Pull Bridges

Push Bridges

Tagging and Exclusion

Durability

...

Please note: Whereas broker federation was introduced in the M3 milestone release, the discussion in this document is based on the richer capabilities of federation in the M4 release.

This document presents broker federation for the administrative user. For design and developer information, please see (link).

What Is Broker Federation?

The Qpid C++ messaging broker supports broker federation, a mechanism by which large messaging networks can be built using multiple brokers. Some scenarios in which federation is useful:

• Connecting disparate locations across a wide area network. In this case full connectivity across the enterprise can be achieved while keeping local message traffic isolated to a single location.
• Departmental brokers that have a policy which controls the flow of inter-departmental message traffic.
• Scaling of capacity for expensive broker operations. High-function exchanges like the XML exchange can be replicated to scale performance.
• Some applications benefit from having a broker co-resident with the client. This is particularly true if the client produces data that must be delivered reliably but connectivity to the consumer(s) is non-reliable. In this case, a co-resident broker provides queueing and durablilty not available in the client alone.

The qpid-route Utility

The qpid-route command line utility is provided with the Qpid broker. This utility is used to configure federated networks of brokers and to view the status and topology of networks.

In the following sections, federation concepts will be introduced and illustrated using qpid-route.

Links and Routes

Federation occurs when a link is established between two brokers and one or more routes are created within that link. A link is a transport level connection (tcp, rdma, ssl, etc.) initiated by one broker and accepted by another. The initiating broker assumes the role of client with regard to
the connection. The accepting broker annotates the connection as being for federation but otherwise treats it as a normal client connection.

Dynamic Routing

Static Routing

Exchange-to-Exchanges Routes

Queue-to-Exchange Routes

Pull vs. Push Routes

qpid-route Summary and Options

Example Scenarios

Using QPID to bridge disjoint IP networks

...