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+++ b/mod_client_proxy/README.markdown	Sun Jun 03 13:55:10 2018 +0200
@@ -0,0 +1,68 @@
+---
+labels:
+- 'Stage-Alpha'
+summary: 'Proxy multiple client resources behind a single component'
+...
+
+What it does
+============
+
+This module must be used as a component. For example:
+
+    Component "proxy.domain.example" "client_proxy"
+        target_address = "some-user@some-domain.example"
+
+All IQ requests against the proxy host (in the above example:
+proxy.domain.example) are sent to a random resource of the target address (in
+the above example: some-user@some-domain.example). The entity behind the
+target address is called the "implementing client".
+
+The IQ requests are JAT-ed (JAT: Jabber Address Translation) so that when the
+implementing client answers the IQ request, it is sent back to the component,
+which reverts the translation and routes the reply back to the user.
+
+Let us assume that user@some-domain.exmaple sends a request. The
+proxy.domain.example component has the client_proxy module loaded and proxies to
+some-user@some-domain.example. some-user@some-domain.example has two resources,
+/a and /b.
+
+    user -> component:
+        <iq type='get' id='1234' to='proxy.domain.example' from='user@some-domain.example/abc'>
+    component -> implementing client:
+        <iq type='get' id='1234' to='some-user@some-domain.example/a' from='proxy.domain.example/encoded-from'>
+    implementing client -> component:
+        <iq type='result' id='1234' to='proxy.domain.example/encoded-from' from='some-user@some-domain.example/a'>
+    component -> user:
+        <iq type='result' id='1234' to='user@some-domain.example/abc' from='proxy.domain.example'>
+
+The encoded-from resource used in the exchange between the proxy component
+and the implementing client is an implementation-defined string which allows
+the proxy component to revert the JAT.
+
+
+Use cases
+=========
+
+* Implementation of services within clients instead of components, thus making
+  use of the more advanced authentication features.
+* General evilness
+
+
+Configuration
+=============
+
+To use this module, it needs to be loaded on a component:
+
+    Component "proxy.yourdomain.example" "client_proxy"
+        target_address = "implementation@yourdomain.example"
+
+It will then send a subscription request to implementation@yourdomain.example
+which MUST be accepted: this is required so that the component can detect the
+resources to which IQ requests can be dispatched.
+
+
+Limitations
+===========
+
+* It does not handle presence or message stanzas.
+* It does not allow the implementing client to initiate IQ requests