SIP and XMPP are the two main protocols used nowadays for realtime communications with presence and instant messaging. They both offer similar features even though their development started quite differently. They both coexist and the interoperability between the two is key in order to offer a communications solutions which covers a broader number of users.

Throughout the course of time several gateways have been built to convert SIP to XMPP (and the other way around) but never in a fully transparent way. SylkServer implements a transparent gateway for SIP and XMPP. It's Open Source and during the talk I'll comment on its design, what advantages it has and what problems had to be solved.