Lync Server 2013 now integrates the XMPP proxy functionality into the Lync Edge Server. In previous versions, this was a dedicated server role. The XMPP Gateway is also deployed on Front End Servers for internal integration with XMPP Services. Organizations can deploy XMPP federation as an optional component. Deploying XMPP federation will allow users to perform Instant Messaging sessions with XMPP-based contacts such as Google’s GTalk.