An emerging trend among Unified Communications vendors these days is support for federation between UC systems in different organizations. Perhaps the first to market was Microsoft OCS Federation which allows two enterprises with Office Communications Servers to share presence, instant messaging, voice, and video. Google Wave launched last June with support for Wave Federation Protocol which allows wavelets in a wave to be hosted across different organizations. In November, Cisco launched their Intercompany Media Exchange product which uses a protocol called VIPR (Verification Involving PSTN Reachability) for opportunistic federation between participating organizations. Avaya, Cisco/Jabber, Reuters Messaging, Google, and others also support XMPP federation which enables presence and instant messaging to be directly shared between organizations.
What VoIP/ UC Security issues come into play with UC Federation schemes like these? For starters, trust needs to be established between federation partners – this is typically done via digital certificates. But from there we have many policy and identity questions to address, such as:
- Who in my federation partner organization gets to know about my CEO’s presence and availability?
- What thresholds can be set to prevent a federation from becoming the conduit for a Denial of Service attack?
- How does a given E.164 (telephone) number get mapped to the right user@domain handle?
- Is there any way for a federation partner to use my VoIP system for their toll calls (toll fraud)?
During the next few weeks, I’m going to be exploring some of these UC Federation security questions here on the VOIPSA blog along with others raised by you, our loyal readers. Has your organization implemented any UC federation yet? What are the security issues around federation that concern you the most?