| [Stream Management](streammanagement.html) | [XEP-0198](http://xmpp.org/extensions/xep-0198.html) | Allows active management of an XML Stream between two XMPP entities (stanza acknowledgement, stream resumption). |
| [Data Forms](dataforms.html) | [XEP-0004](http://xmpp.org/extensions/xep-0004.html) | Allows to gather data using Forms. |
| Last Activity | [XEP-0012](http://xmpp.org/extensions/xep-0012.html) | Communicating information about the last activity associated with an XMPP entity. |
| Flexible Offline Message Retrieval | [XEP-0013](http://xmpp.org/extensions/xep-0013.html) | Extension for flexible, POP3-like handling of offline messages. |
| [Privacy Lists](privacy.html) | [XEP-0016](http://xmpp.org/extensions/xep-0016.html) | Enabling or disabling communication with other entities. |
| [Message Events](messageevents.html) | [XEP-0022](http://xmpp.org/extensions/xep-0022.html) | Requests and responds to message events. |
| [Service Discovery](disco.html) | [XEP-0030](http://xmpp.org/extensions/xep-0030.html) | Allows to discover services in XMPP entities. |
| Extended Stanza Addressing | [XEP-0033](http://xmpp.org/extensions/xep-0033.html) | Allows to include headers in stanzas in order to specifiy multiple recipients or sub-addresses. |
| [Multi User Chat](muc.html) | [XEP-0045](http://xmpp.org/extensions/xep-0045.html) | Allows configuration of, participation in, and administration of individual text-based conference rooms. |
| In-Band Bytestreams | [XEP-0047](http://xmpp.org/extensions/xep-0047.html) | Enables any two entities to establish a one-to-one bytestream between themselves using plain XMPP. |
| Bookmarks | [XEP-0048](http://xmpp.org/extensions/xep-0048.html) | Bookmarks, for e.g. MUC and web pages. |
| Advanced Message Processing | [XEP-0079](http://xmpp.org/extensions/xep-0079.html) | Enables entities to request, and servers to perform, advanced processing of XMPP message stanzas. |
| XMPP Date Time Profiles | [XEP-0082](http://xmpp.org/extensions/xep-0082.html) | Standardization of Date and Time representation in XMPP. |
| Chat State Notifications | [XEP-0085](http://xmpp.org/extensions/xep-0085.html) | Communicating the status of a user in a chat session. |
| [Time Exchange](time.html) | [XEP-0090](http://xmpp.org/extensions/xep-0090.html) | Allows local time information to be shared between users. |
| Software Version | [XEP-0092](http://xmpp.org/extensions/xep-0092.html) | Retrieve and announce the software application of an XMPP entity. |
| Stream Initation | [XEP-0095](http://xmpp.org/extensions/xep-0095.html) | Initiating a data stream between any two XMPP entities. |
| [SI File Transfer](filetransfer.html) | [XEP-0096](http://xmpp.org/extensions/xep-0096.html) | Transfer files between two users over XMPP. |
| [Entity Capabilities](caps.html) | [XEP-0115](http://xmpp.org/extensions/xep-0115.html) | Broadcasting and dynamic discovery of entity capabilities. |
| Stream Compression | [XEP-0138](http://xmpp.org/extensions/xep-0138.html) | Support for optional compression of the XMPP stream.
| Personal Eventing Protocol | [XEP-0163](http://xmpp.org/extensions/xep-0163.html) | Using the XMPP publish-subscribe protocol to broadcast state change events associated with a XMPP account. |
| Message Delivery Receipts | [XEP-0184](http://xmpp.org/extensions/xep-0184.html) | Extension for message delivery receipts. The sender can request notification that the message has been delivered. |
| XMPP Ping | [XEP-0199](http://xmpp.org/extensions/xep-0199.html) | Sending application-level pings over XML streams.
| Entity Time | [XEP-0202](http://xmpp.org/extensions/xep-0202.html) | Allows entities to communicate their local time |
| Delayed Delivery | [XEP-0203](http://xmpp.org/extensions/xep-0203.html) | Extension for communicating the fact that an XML stanza has been delivered with a delay. |
| XMPP Over BOSH | [XEP-0206](http://xmpp.org/extensions/xep-0206.html) | Use Bidirectional-streams Over Synchronous HTTP (BOSH) to transport XMPP stanzas. |
| [Group Chat Invitations](invitation.html) | n/a | Send invitations to other users to join a group chat room. |
| [Jive Properties](properties.html) | n/a | TODO |
Experimental Smack Extensions and currently supported XEPs by Smack (smack-experimental)
| Message Carbons | [XEP-0280](http://xmpp.org/extensions/xep-0280.html) | Keep all IM clients for a user engaged in a conversation, by carbon-copy outbound messages to all interested resources.
| [HTTP over XMPP transport](hoxt.html) | [XEP-0332](http://xmpp.org/extensions/xep-0332.html) | Allows to transport HTTP communication over XMPP peer-to-peer networks. |
| [Roster Item Exchange](rosterexchange.html) | [XEP-0093](http://xmpp.org/extensions/xep-0093.html) | Allows roster data to be shared between users. |