docs/books/modules/user-guide/configuring-address-semantics.adoc

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// This module is included in the following assemblies:
//
// configuring-address-space-message-routing.adoc

[id='configuring-address-semantics-{context}']
= Configuring address semantics

You can route messages between clients without using a broker. In a brokerless scenario (sometimes called _direct-routed messaging_), {RouterName} routes messages between clients directly.

To route messages between clients, you configure an address with a routing distribution pattern. When a router receives a message with this address, the message is routed to its destination or destinations based on the address's routing distribution pattern.

.Procedure

. In the `{RouterConfigFile}` configuration file, add an `address` section.
+
--
[options="nowrap",subs="+quotes"]
----
address {
    prefix: my_address
    distribution: multicast
    ...
}
----

`prefix` | `pattern`::
The address or group of addresses to which the address settings should be applied. You can specify a prefix to match an exact address or beginning segment of an address. Alternatively, you can specify a pattern to match an address using wildcards.
+
include::{FragmentDir}/fragment-prefix-matching-definition.adoc[]
+
include::{FragmentDir}/fragment-pattern-matching-definition.adoc[]

`distribution`:: The message distribution pattern. The default is `balanced`, but you can specify any of the following options:
+
* `balanced` - Messages sent to the address will be routed to one of the receivers, and the routing network will attempt to balance the traffic load based on the rate of settlement.
* `closest` - Messages sent to the address are sent on the shortest path to reach the destination. It means that if there are multiple receivers for the same address, only the closest one will receive the message.
* `multicast` - Messages are sent to all receivers that are attached to the address in a _publish/subscribe_ model.
+
For more information about message distribution patterns, see xref:routing-patterns-message-routing-{context}[].

For information about additional attributes, see link:{qdrouterdConfManPageUrl}#_address[address] in the `qdrouterd.conf` man page.
--

. Add the same `address` section to any other routers that need to use the address.
+
The `address` that you added to this router configuration file only controls how this router distributes messages sent to the address. If you have additional routers in your router network that should distribute messages for this address, then you must add the same `address` section to each of their configuration files.