NTT: one of the biggest IMS & PoC deployment so far

Over the last years NTT has deployed more than 30 million of PoC handsets in its advanced 3G FOMA network. The service was launched as "PushTalk" in late 2005. Now, 30 million handsets is a small fraction of the market but a significant number compared to the tiny deployments made so far.

Service relies on NEC IMS core, technical details are not clear, but we can safely bet this is the biggest mobile IMS deployment so far. PoC or PTT are terms not mentioned by NTT, perhaps they are using a proprietary, IMS-based, protocol.

The basic service includes group calls up to 5 participants, for larger groups an additional service must be contracted (PushTalk Plus), aimed at enterprises. Service is billed per push (0,03€ per push) and there is a flat rate (Kake-Hodai) service for 6,45€ per month.
PushTalk Plus service, including group calls up to 20 members, is 12,9€ per month.

And a very interesting detail: Service is activated by default in every handset for every subscriber. I don't know the reason for that, but one very important consequence: you needn't to know in advance if the person you want to call has the service or not: everybody "is in the service". And the person receiving the call will probably answer back. This scheme encourages service spreading from a small number of knowledgeable users to the rest. From my point of view, this is much better than waiting for the subscribers to ask for activation, or trying to communicate with other subscribers only to find that they are not subscribed.

Japan is a very innovative market, we are looking forward to reading some data about service usage, would that be a test of things to come?