A few weeks ago I wrote Enough Sip / Skype Foolishness, which indexed a wider blog discussion about whether Skype was replacing SIP. This piece got a fair bit of attention after being picked up and linked by Jeff Pulver. Since then a number of people, including some of the net luminaries, have weighed in on the dialog.
Here, then, is an update on the dialog, followed by some refinements and further thoughts on my original post.
- I was honored that Henry Sinnreich wrote a guest blog entry on Jeff Pulver’s blog referring to my post, in which he agrees with some of my points but holds out hope for solving SIP/URI addressing problems
- Brough Turner added these thoughts
- Richard Stastny made additional excellent points about sip:user@host nomenclature, pointing out that your average user should no more need to manage this than manage the DNS entry for his email address – your ISP should do this. (I agree and comment further on this theme below)
- Aswath wrote just early this week, noting that the hype flavor-of-the-month is a the new miracle cure-all protocol, in a plea to stop bickering about who has the best protocol and just make things work.
- I also had discussions about this topic with Phil Wolff of the Skype Journal, Bob Frankston, the ubiquitous Jeff Pulver, and a few other colleagues.
Even as I penned my original essay and hit the commit button, I knew that I hadn’t really thought through my comments about addressing and URIs.
Using the PSTN dialing address space for reaching SIP endpoints, and using ATAs and black phones significantly restrains the user experience. I think we’re all agreed.
Today’s soft phones are to varying degrees complex to configure, although some like the Pulver Communicator have made big strides. However, even the best of them is more complex than Skype. I think we’re all agreed.
However, I said that the average user can’t create and manage a SIP URI, and this was at best incompletely thought out and at worst just plain wrong. As Richard pointed out, this should be the role of an ISP or other service provider. Both to maintain your URI and to act as your proxy.
In fact, many services exist to do this, one of note is iptel.org. In many cases for free you can go create a free sip uri, and then configure your soft phone to use the service as a proxy. This existence proof shows it should not be hard for ISPs to start adding this service to go along with your email account. If you know you can email johndoe@comcast.net, presumably you could call him at sip:johndoe@comcast.net. Now, Comcast doesn’t do this yet, but they could. Hey pobox.com, wanna extend your value add, give your customer’s SIP URIs and point them to the Pulver Communicator or other free soft phone.
Note that the beauty of SIP/RTP is that call signalling and setup is separate from media. Thus the load on resources to manage a proxy and the URI is light. The media streams directly between the two endpoints, without having to pass through the proxy and consume bandwidth.
Now, the SIP URI addressing hasn’t been widely adopted yet, because no-one has made it easy to setup, configure, and use. Versus Skype. But that’s not to say that it can’t be done. Henry has joined Pulver, and says one of the things he is hoping to do is to promote use of the SIP URIs. The protocols as designed are simple and appropriate, they should be used. Good luck Henry!
One other correction I’d like to make to my original post is that I said that Skype has nailed C2C, but is not good at much else. Well, it may be trite to say it, but SkypeOut works very well for C2B, the only minor nit being a strange ANI. And in some B2B use cases and E2E use cases it works well. How many global enterprise executives are using Skype to communicate these days? I know of at least a few …