Allright, a couple of weeks ago I had a chat with a friend, Antonio, here in Mexico City, who works for a company that provides IMS platform to telco operators, in my attempt to get another perspective on IMS.
Remember, on the earlier chat with another friend, Eric, who comes from a different background, all we got was skepticism. Basically the questions he posed were:
- Why trying to be an "app-store", another "me too"?
- Why transmiting the voice -- between the mobile 3G handset and the operator -- in IP, when the infrastructure for voice transmission (non IP) is already there, working just fine? Plus we know what it takes to transmit voice over IP... serializing, packetizing, unpacketizing, deserializing, etc. It sounds like a lot of things to do, compared to simply transmiting the voice signal as, you know, waveform (that's how they basically do it, right?).
Yadda-yadda from me: this skepticism here is not nay-saying; quite the contrary. I am enthusiastic about this whole IMS thing, and I do plan to put (some of) my eggs in it. But I need to validate some of my assumptions; "this will definitely work and become a boom very soon :-)" being one of them. I would say I'm trying to do some reality checks.
For the second question above, the way I see it: if it's doable why not? I mean, the cost of operating a single infrastructure (IP for all) should be cheaper, right? I need some hard facts, some figures might help. If you have happen to have a link to that information, please share it with us.
Assuming that is true, then the next question would or should be: why haven't they done it? Why are voice calls still transmitted over non-IP channel? Allright, I don't know the answers, so I asked my friend Antonio. Here are the answers, verbatim copy, which to my (momentarily) lazy mind boil down to "it's all about money":
- Mobile networks are good businesses even if they don't use IP. Operational margin in most MNOs (such as Telcel, for example) is so good, that the supposed savings coming from the IP change don't look so compelling. At least, not yet. SDH is still being supported and it does not imply large OPEX (yet).
- Elaborating on the previous reason. Even though IP-based transport is said to be cheap, so it is the TDM-based one. SDH and WDM technologies have improved and became cheaper a great deal during the last 3-5 years. Many network operators have made large investments in TDM-based transport less than 3-4 years ago. In their view, that investment has not paid off enough as yet. The ROI (Return on Investment) has not been satisfactory enough in many cases. Many MNOs are waiting for their SDH/WDM networks to depreciate even more.
- Paraphrasing some famous TV program: "what is the other option, anyway?"... what I mean by this is: if the MNO is supposed to throw away its SDH network, what is he supposed to buy instead? the common word in the last years is called Metro Ethernet. The truth is: even if Metro Ethernet can look as cheap as SDH in terms of $$$ per Mbps, it doesn't look as mature in other aspects, especially regarding O&M capabilities. The ones who are operating SDH networks are today very familiar with its ways of operation and maintenance, and know very well how to troubleshoot these circuit-based networks. It just does not look as clear in the case of Metro Ethernet.
- Lack of know-how on IP-based technologies. Even if the change seems inevitable (it really is), there is a lot of reluctancy within the engineering and operation organizations of the MNOs to move towards the all-IP paradigm. They just don't know enough of IP to take such an important decisions.
I'll process those information later. I keep it here for my future references. Now, where am I heading, or where am I in my train of thoughts? Allright, I guess the question #2 by Eric has been addressed (more or less).
However, I really don't understand why should I be concerned (too much) about this? I mean this whole rant I'm putting here is actually just a prelude to the point I want to bring up: the switch to IP is inevitable, they're going to do it, just wait (1-2 years, depends on which country you live in), and IMS is there just waiting for adoption, as it provides the architectural framework for their needs (by the time they've switched to full IP). For me -- as software developer trying to profit from that -- that means: my investment in learning SIP Servlet, IMS, and stuffs wouldn't become a waste. That's all I wanted to say. Well, that's what I want to believe.
The kind of application I'm thinking of that I can develop is some mobile applications (together with some server side components implemented as SIP Servlet) that enables funky (yet useful) interaction scenarios (voice, image, video, etc), connected to things like social network, document management, customer management, etc., taking advantage of the nature of the protocols that enables that kind of service convergence. For that kind of applications I don't think I really need to care whether the voice is transmitted over IP or TDM. Or am I wrong? Can you tell me what kind of scenarios wouldn't be possible if the voice / video is not transmitted over IP?
Anyway, let's move on to the question #1 from Eric: why trying to be an "app-store", another "me too"?
I don't know :) So please chip in here. Anyway, in the process of trying to find the answer / get some insights, I came across this thing called SDP (service delivery platform). I was looking at a product from a company JNetX.com. Hmm, well it seems to be one of the building-block for an "app-store" of telco. I need to find out how they go, the clients they have, the reasons those clients use their product, maybe that way I'll arrive at the answer for question #1.
Wrapping up..., I need to:
- Find an information that says : the cost of using IP for all their service is be cheaper.
- Try to process the points mentioned by Antonio.
- Keep this question alive: what scenarios would be made possible (only) if the voice & video is transmitted in IP?
- Dig service delivery platform (SDP).
