SIP interoperability: call anywhere? do you really want to do that?

There is on-going discussion whether “call anywhere always” is really desired. For example, the ability to make an audio-only call (from a mobile phone) into a video conference is obviously useful for somebody who is at an airport and need to participate in that meeting, However, sitting in front of your PC, do you really want to look up a person in your address book, make a call, and then see what happens as the person can be on IM only right now or maybe in an on-going meeting?

I think there is more agreement to the basic idea that people need a way to know how other people can be reached, so they can pick the preferred way they want to communicate. If I see that Mary can be reached on Facebook chat (she’s online), MSN (offline because she is at a friend’s house borrowing a computer), and through an SMS or call to her mobile phone, I may be tempted to try Facebook if the topic is low-priority and maybe call her on her mobile if it’s important or we need to discuss in-depth.

Ok, so we can open closed gardens using some kind of interoperability, Skype adds Skype-in and Skype-out for PSTN interoperability or consolidation can be done through the user adding all sorts of clients on her device (and maybe gets some help from the device vendor to consolidate everything, like what Sony-Ericsson is doing for Xperia X10). The problem with interoperability is that you always end up with lowest common denominator, the problem with consolidation is that your different devices will offer you very different views of your network and contacts.

There’s no doubt that consolidation is the quickest way to give users a rich experience. But will there be a difference between the consumer industry and enterprise? As smartphones seem to push the consolidation and enterprise employees are important buyer groups of these phones, it may seem likely that the battle of unified communications in the enterprise may be forced over to the handset.

One final element of the call anywhere idea: it is connected to the concept of being able to reach anybody capable of communicating the same way you do. Voice, video, and IM are example of very generic ways of communicating (where email, chat, and SMS can be seen as variations of instant messaging). If we see a phone number, we assume that we can call that number and talk to somebody. If we see an email address, we expect to be able to send email. But we don’t assume that we can make a voice (or maybe even a video) call to an email address.

It is my belief that we over time will develop a shared platform of the basic ways of communicating and that we need a way to infer from an address (number or email or ?) how we can communicate with that address. There will be schemes of unified addresses (one address, maybe your openid?) and there will be addresses that are specific to just one method of communication. However, I believe that we eventually will expect to be able to reach most people using voice, video, and messaging (both instant and asynchronous like email and Facebook). Interoperability on these functionalities will slowly develop until the world’s shared communication platform is not just voice and email, but also messaging and video, while consolidation will always be able to enable a richer user experience.