Almost exactly a year ago, I published a report on the severe problems involved in getting IMS-capable mobile phones to market. At the time, I'd been tracking the area for around 18 months - it was blindingly obvious that the 3GPP and other standards bodies had effectively abdicated all responsibility for actually making sure IMS actually worked on handsets in the hands of the user. Yes, the basic plumbing like SIP signalling was standardised. But there were dozens of companies trying to develop their own, proprietary software and UI frameworks for IMS, usually with a bunch of in-house applications.
The standards had been driven largely by network infrastructure people, who had simply assumed that phones would "naturally follow" and would have a user interfaces "defined by the market". That might have been true in the early days of GSM, when handset software was confined to a dialler and phonebooks, but is woefully inadequate today, where phones OS, application and UI software runs to millions of lines of code, with a high % of the pain of any handset development project related to software integration and testing.
It was clearly a poor situation for most operators, handset OEMs and application/service developers, and has contributed to the dearth of serious IMS rollout in the mobile industry. What was supposed to be a cellular core IP technology has instead been adopted more quickly in the fixed-VoIP and even WiMAX sectors.
So yesterday's announcement by the OMTP (a group of operators that try and harmonise handset user interface requirements) that they have finally published a requirements document for IMS-capable handsets is very welcome, but about 3 years overdue. To be fair to the OMTP, they recognise that the standardisation process has been lacking "In its current form the IMS proposition fails to sufficiently address these four key areas and falls short of the full end-to-end experience that is required".
I haven't had a chance to read the full spec yet, but I spoke to the OMTP recently and it certainly seems as though they've tackled some of the main deficiencies, although I suspect that there will need to be a couple of subsequent iterations before the IMS on-handset experience is truly integrated with all the other non-IMS functions of the phone.
As the organisation is specifically about phones, it also doesn't address the issue of IMS application development and distribution. For me, one of the worst things about IMS is that it doesn't support the type of broad innovation and ultrarapid, viral, cross-network uptake that drives the Internet / Web 2.0 world. A small startup in Santa Clara or Bangalore cannot develop a cool IMS app, "put it out there" in beta form, and have 10m people around the world download it and forward a link to their friends (irrespective of their operator) by next Wednesday.
Incidentally, for those readers new to the OMTP, you might be interested to check out the list of work items here. Especially the one innocuously called "Multipath Routing", which is actually about controlling VoIP clients on handsets, and which includes the rather unambiguous objective to "ensure that terminal platforms have the capability to offer mobile operators the opportunity to uphold current business practise". Supposedly, this will only apply to subsidised handsets though.
Lastly... a word of advice to OMTP. Rename yourself OMDP or OMHP (Device, or Handset). The word "terminal" ought to be expunged from the mobile industry - it's exactly why things like IMS are in the troubled state we have here. People from the network side still routinely ignore the fact that millions of handsets with 200MHz-1GHz processors now constitute the overwhelming proportion of intelligence in the mobile ecosystem. "Terminal" comes from a centralised, 1970s mainframe/green-screen view of the world. Wake up and listen to Moore's Law.