17th level Hacker

SIP and Mobile Services

Bill brought up some excellent topics at his presentation at BAMF this weekend. The one that struck me the most was his mention of SIP as a major item for future development of mobile applications. Given that right before the meeting I was blogging that I wanted ”a service that respects my mobile device not as a remote and minimal information terminal, but as a first class node within a worldwide network” that really grabbed my attention. I was somewhat familiar with SIP (Session Initiation Protocol) from the Voice Over IP side. SIP is used in some VOIP implementations, and has been around for a while. I wasn’t at all familiar with the proposed uses within the mobile realm. For a quick techie overview of the protocols, which should make sense to anyone familiar with basic networking, check out this overview from Cisco. For information about how SIP fits into mobile applications, check out the FAQ from Forum Nokia. Just fucking fantastic stuff. They address issues of IM and presence over the mobile networks and programmed handset to handset communication.

“So what?” you say. You really aren’t impressed by handset to handset communication, and you really have no need for messaging or presence. Okay, no problem there. This set of features isn’t for everyone. But it also enables a whole other set of applications that I think are mostly being overlooked right now - non-handset devices out on the cellular network. We’re seeing IP functionality merging down into the core of devices like stereo systems, video entertainment systems, security products, and home appliances. Most of these assume they get hooked into a home network of some sort, in general they’re stuck tethered to your home, and have to rely on a third party provider to facilitate the rendezvous so that you can communicate with them when you’re not at home (or a lot of technical expertise to make it so that you can communicate with them on your own). The information in the FAQ makes it sound like SIP would bring us a long way toward mobile devices that could act not only as a consumer of service, but a server for new features as well. Sounds like some kick ass stuff. In particular I would love to experiment with IM and presence that was uniform on mobile and desktop systems. I use IM as a major part of my workday, and I would like to be able to sign in to IM when I’m wandering around. Mark myself as “available, but on my mobile.” Sure, some services are setup so that I can use them from my mobile. Take AIM for instance, they have a few methods of using AIM from mobiles. That’s a step in the right direction, and gives me partial connectivity, but AIM is only one of the services I use. I might be a hot mobile studmuffin, but not everyone is going to switch to AIM just so that they can talk to me. What I would like to be able to do is hook my Jabber server up to my mobile device, so that I can sign on to the IM account I want via SMS, not just the one my provider has server side hookups for. SIP seems to be a step in the right direction as far as I’m concerned, especially with relation to these kinds of issues. Move some of the logic off the gateways and out to the edges, keep the network dumb and have it just route uniform packets. Just like on that big Internet thing, where intelligence at the edges seems to be working quite well.