Friday, April 13, 2007

Why dedicating a blog to IMS?

The main reason why I decided to write on IMS (as well as on adjacent topics) is that these days everybody in the telecommunications industy seems to have an opinion on it, and you can read basically everything and its opposite.

For some, IMS is this ugly telecommunications monster, that tries to recreate an old-fashioned telco world over IP and that will be ripped to pieces by the conquering Internet industry.
For others, IMS is the possibility for the telco industry to be part of web 2.0 (or web 3.0) and to positively contribute to the future of a converged telco/Internet world.

For some, IMS can be reduced to a single protocol, SIP (Session Initiation Protocol), and is doomed to fail because SIP will never conquer the Internet.
For others, SIP is just one protocol that will be used by IMS services, a key one for sure, but one among many others.

For some, SIP could as well be called "SS7 over IP", as SIP is a fairly complex signalling protocol to support voice sessions over IP.
For others, voice sessions are just the tip of the SIP iceberg, as SIP is a very powerful and generic service control protocol.

For some, IMS is just a "new IN", and by saying so they strongly limit the scope and potential for success of IMS.
For others, comparing IMS to IN is the biggest mistake one can make when evaluating the potential of IMS.

For some, the problem with IMS is that it is too complex and aims at centralizing all control in the network, while SIP was initially defined as a protocol supporting intelligence at the edges of the network.
For others, the complexity of IMS has value, as long as it provides supports to applications while keeping its complexity hidden to them. Instead of staring at the internals of the IMS watch, people should rather look at what these internals can be used for: showing the time and date in a simple manner.

For some, the only valid architecture in the future implies intelligent edges and stupid networks.
For others, intelligence both at the edges and in the network can also offer advantages.

For some, IMS is essentially a core network complemented by an application layer, just like the old voice-centric circuit-switched network was complemented by IN servers.
For others, IMS is essentially a service network supported by what people call a core network, but for which a better name could be "service bus" or "network middleware". This is a simple, but fundamental reversal of the picture to understand the potential of IMS.

For some, SIP is a network control protocol, while web services and SOA are THE way to implement services on top of the network.
For others, SIP/IMS and Web Services/SOA complement each other, and may eventually result in a new architecture that could be called "UOA" (for "User Oriented Architecture").

Finally, for some, the brilliant or dark future of IMS is already written in its specifications.
For others, IMS specifications can be interpreted in so many different ways that the future of IMS is still to be defined. Depending on the ability of the Telco industry to overcome its organizational and cultural handicaps, IMS may either be a spectacular failure or the beginning of a new era.

In the future, I will try to explain why I belong to the "others".

Thanks for reading, and apologies for my "Franglish".

Christophe

4 comments:

Rohit said...

Thanks for the wonderful blog on IMS. How do I increase my knowledge about telecom to gain an insight into this field?

Chitra said...

I have been reading texts, 3GPP specifications, IETF drafts, attending conferences and presentations on IMS, SIP and the so called convergence. I have always ended up with conflicting views when I try to place IMS in the "Big picture". You seem to have summed all those conflicting views and confusion in one post. I have begun from the very beginning , your first post and I hope to unclutter my confusions as i go along reading your blog!. Last but not least, a big! salute for starting a blog which seems very different (atleast from your first post and as i scanned through all the post headings) from the hoards of other IMS/web 2.0 related blogs.

Christophe Gourraud said...

Hi Chitra,

Thanks for the good words.

I think that at the moment there is little knowledge about the potential of IMS, and therefore little consensus on how it can benefit the telco industry and end-users.

Here follow some potential reasons for it.

The legacy telco culture, which has difficulties to view the IMS as something else than a new way to re-implement existing telco services over IP.

The fact that IMS was essentially specified as a core network, while its true potential is application-oriented. Within existing telco companies (equipment suppliers and operators) the IMS tends to be "owned" by network organizations, which by definition do not care about services other than voice, while application layer organizations have little knowledge and interest for something they view as another telco network.

The fact that IMS specifications, litterature and trainings focus on protocol and core network issues and do not help understanding IMS from an application perspective.

The inability (unwillingness?) of IMS suppliers to "sell" IMS beyond buzzwords (multimedia, convergence, web 2.0) they cannot detail further.

The fact that IMS is a potentially revolutionary technology, and that revolutions usually come with blood shed and victims. What I mean is that to exploit IMS you need to rethink your organizations and the way you work. IMS is also the first technology enabling a real convergence between communication and data, telecommunications and IT, telecommunications and the Internet (all of which having been announced for many years). This may strongly reshape the market and some telco kings of today may see their market share shrink in favour of companies with a different background.

The fact that the telecommunications industry is in a deep soul searching period, which does not help being confident in taking any direction. There is a frantic search for silver bullets, and simple (simplistic) answers to very complex problems. IMS is too complex to understand compare to some alternatives, which have at least the interest to be simple.

Christophe

Christophe Gourraud said...

To Rohit...

You can purchase a book on IMS (several are available from Amazon for instance) or attend a training.

However, you are likely to get deep knowledge about the protocols and the IMS core network without necessarily see any sense of purpose over than implementing VoIP, presence or messaging using IMS.

This is the reason why I started this blog in order to express some ideas, good or bad, that you will have difficulties to find somewhere else.

Christophe