Going through my pile of 1 million things to read before I die, I came across this presentation by Tekelec with regards to why Diamater and SIP would be used instead of SS7 in LTE and IMS. The slide in the picture above shows the comparison of SS7 and Diamater.
More and more operators are asking for replacement of SS7 with the Diamater interface. The main reason being that it has been adopted by 3GPP and when we move to an all IP network as in case of LTE it makes sense to have Diamater instead of SS7. There is a good description of Diameter on Wikipedia (cant guarantee the accuracy though) here.
You can read more about SIP at the Tekelec blog here.
There is also an interesting Radvision presentation on Slideshare that I have embedded below:
IMS 2.0 world forum is a must attend event .. I learnt a lot from it. Here is a brief synopsis of where I see IMS is heading to .. Seek your thoughts and feedback especially you can identify other Operators with an interesting strategy and / or if you attended this event
As I could gather, there are six broad strategies: a) Voice call continuity(VCC) / fixed to mobile convergence b) Blended voice : voice tied contextually to messaging or rich media c) SIP without IMS (Naked SIP) d) Strategies from device manufacturers(especially Nokia and Motorola) e) Real time IMS applications (multiplayer games and other such applications that need near real time blended media interaction within a session) f) Abstraction of the core network
Most of the focus is around (a) Voice call continuity(VCC) / fixed to mobile convergence
This is a pity – but also understandable Operators are most familiar with voice In its broadest sense, voice call continuity pertains to roaming within cellular and non cellular networks(such as roaming between cellular and wifi networks). A specific instance of this is Fixed to mobile convergence for instance BT fusion My personal view is:
a) I don’t quite know if I would be interested in FMC as a customer .. b) I think its being sold on cost – which is not a good idea c) I think it fulfils an industry goal(fixed and mobile networks trying to get new subscribers from each other’s networks in mature markets) d) In general, voice is becoming cheap .. so I am not sure that a pure voice play is a good idea
Blended voice(b) and real time applications(e) are interesting but need device support. Devices supporting IMS fully are conspicuous by their absence!
In contrast, devices supporting SIP(c) - but not IMS are very much here and so are applications – for instance movial
Abstracting the network layer through software APIs(f) – is the most interesting – but I felt very few Operators had the vision to embrace this strategy at the moment. The two big exceptions being TIM and Telia sonera - who are doing some very interesting work.
To recap, by abstracting the network layer, I mean : In an IP world, as the Mobile Internet mirrors the Internet, the Operator should focus on the core of the network and leave the edge of the network to third parties. Specifically, this means – identify the elements that can be performed ONLY in the core and then abstract them through APIs. This approach gets us away from the dichotomy of the ‘pipe’ vs. ‘no pipe’. It also means that the Operator retains control.
Finally, Operators in emerging markets like Globe telecom from Philippines were also impressive i.e. they understood the space, the issues specific to their market and how they could leverage IMS in their markets. Harvey G Libarnes, Head of innovation and incubations program , Globe Telecom, gave a very thorogh presentation
To conclude: a) At Operator level, IMS is still largely about voice and a defensive approach(such as FMC) b) Lack of devices is the key question mark c) Device manufacturers on the other hand have significant leverage(more on that soon) d) Some operators are going to be very innovative – TIM and Teliasonera from amongst the attendees