How this services-config.xml works?

Question

I going through some  gettingstarted examples of using flex with AMFPHP I got it working. But to be honest, I don’t understand this services-config.xml file
Given:
<?xml version="1.0" encoding="UTF-8"?>
<services-config>
      <services>
            <service id="remoting-service"
            class="flex.messaging.services.RemotingService"
            messageTypes="flex.messaging.messages.RemotingMessage">
                  <destination id="amfphp">
                        <channels>
                              <channel ref="my-amfphp"/>
                        </channels>
                        <properties>
                              <source>*</source>
                        </properties>
                  </destination>
            </service>
      </services>
      <channels>
            <channel-definition id="my-amfphp" class="mx.messaging.channels.AMFChannel">
                  <endpoint uri="http://localhost/amfphp/gateway.php"
                  class="flex.messaging.endpoints.AMFEndpoint"/>
            </channel-definition>
      </channels>
</services-config>
The only info from that file i use in my RemoteObject is this destination atttribut:
<mx:RemoteObject destination="amfphp" …/>
But what I don’t understand way they split the services-tag from channels-tag and most important how do they relate? Could somebody explain this or hint me to some easy to understand tutorial?
I tried to read adobe livedocs on Using RPC Components etc but it is so confusing, to be honest i don’t understand a word of it. what exacly is service-tag and channel-tag and whay i have to use both of them- i mean one will never switch my amfphp endpoint at runtime, will one? And way?
(ok, that destination has channel ref which reference the “other” channel-tag which points to my amfphp-gateway -but so what? what does it mean, way so commplicated - Wouldn’t it be easier if one would jut give the endpoint attribute to the RemoteObject and everything is fine?)
Thankful for any help

Answer 1

Maybe this will help?
http://www.sephiroth.it/tutorials/flashPHP/flex_remoteobject/page001.php