Split from XEP-0313, no protocol changes
+This specification describes a protocol for a server to allow a client to configure a user's + message archiving preferences. It is intended to be used in conjunction with &xep0313;.
+ +After observing XEP-0313 usage in the wild, it became apparent that preferences were not often + used, and can interfere with clients that use the archive for synchronization of messages received + by the user while disconnected. Therefore it is not actively encouraged for an implementation/deployment + to offer this functionality.
+Depending on implementation and deployment policies, a server MAY allow the user to have control + over the server's archiving behaviour. This specification defines a basic protocol for this, and + also allows a server to offer more advanced configuration to a user.
+If the server supports and allows configuration of the preferences described below then it SHOULD implement the protocol defined + in this section. This allows the user to retrieve and configure the following preferences:
+The server replies with the user's current archiving preferences. The <prefs> element + MUST be present and contain the current default archiving policy. The <always> and <never> + MUST also be present (even if empty), and contain a list of JIDs enclosed in <jid> elements.
+ +It is also possible that the server may respond with a stanza error, for example the standard + 'feature-not-implemented' (server does not support MAM configuration) defined in &rfc6120;.
+ +To update the preferences, the client can simply send an iq stanza with a type of 'set':
+ +The server then replies with the applied preferences (note that due to server policies these + MAY be different to the preferences sent by the client):
+It is also possible for the server to respond with an error, for example (but not limited to) + the standard 'feature-not-implemented' (the server does not support configuration of preferences), + 'forbidden' (the user is not authorized to change their preferences) or 'not-allowed' (the server + generally does not allow changing of configuration preferences).
+ +If a JID is in neither the 'always archive' nor the 'never archive' list then whether it + is archived depends on this setting, the default. +
+The 'default' attribute of the 'prefs' element MUST be one of the following values:
+The <prefs/> element MAY contain an <always/> child element. If present, it + contains a list of <jid/> elements, each containing a single JID. The server SHOULD + archive any messages to/from this JID (see 'JID matching'). +
+If missing from the preferences, <always/> SHOULD be assumed by the server to be an + empty list. +
+The <prefs/> element MAY contain an <never/> child element. If present, it + contains a list of <jid/> elements, each containing a single JID. The server SHOULD + NOT archive any messages to/from this JID (see 'JID matching'). +
+If missing from the preferences, <never/> SHOULD be assumed by the server to be an + empty list. +
+In addition to this protocol, a server MAY offer more advanced configuration to the user + through &xep0050;. Such an interface might, for example, allow the user to configure what + types of messages to store, or set a limit on how long messages should remain in the + archive.
+If supported, such a configuration command SHOULD be presented on the well-defined + command node of "urn:xmpp:mam#configure".
+When comparing the message target JID against the user's roster (ie. when the user has + set default='roster') the comparison MUST use the bare target JID (that is, stripped of + any resource). +
+For matching against entries in either the 'allow' or 'never' lists, for each listed + JID: +
+For outgoing messages, the server MUST use the value of the 'to' attribute as the target JID. +
+For incoming messages, the server MUST use the value of the 'from' attribute as the target JID. +
+Split off from XEP-0313 v0.6.3 to ease advancement of that XEP and allow further clarification and expansion of pubsub use cases.
+This document specifies how to use &xep0313; in combination with &xep0060; to host and query archives on pubsub nodes.
+When querying a pubsub node's archive, the 'node' attribute is added to the <query> element.
+A PubSub service offering MAM SHOULD store each of the items published to each node. When responding to MAM requests it MUST construct the message stanza within the <forwarded> element in the same manner as the notifications sent to subscribers for the item, except that specifying the 'from' 'to' and 'id' attributes are OPTIONAL. Pubsub items must be returned one per message stanza (i.e. there MUST NOT be multiple <item> elements within the <items> element).
+Add fallback to dialback if EXTERNAL authentication fails due to practical experience.
Implementation Note: If Server2 needs to assign an authorization identity during SASL negotiation, it SHOULD use the value of the 'from' attribute of the stream header sent by Server1.
Else Server2 SHOULD return a ¬authorized; stream error and close the stream.
+Else Server2 SHOULD return a ¬authorized; error and either close Server1's TCP connection or continue with a Server Dialback (XEP-0220) [8] negotiation.