Mtnl teaming up with Aksh opti , has started harnessing its broadband capabilities by starting the first official Sip in this country. Read Voip
In Sip or Session Initiation Protocol u have a dedicated Phone like whose back end is the Mtnls net based Sip server connected via Tcp/Ip or Udp instead of the regular Pstn network.Thus u can say that is an always on Voip phone, wherein u get a dedicated phone number. The basic requirements are Mtnls broadband connection coupled with a net Adapter cum router device to which u can connect a regular phone.
Thus PSTN telephone, Broadband Internet, IPTV & VoIP phone will all work simultaneously on your telephone line, sharing the available bandwidth of the 2 mb line.
MTNL VoIP service uses the bandwidth efficient voice coder G.729 which will use only 35Kbps bandwidth for a call.The bandwidth used is free and taken care of thru the rentals. Mtnl provides you with an 8 digit SIP ID number starting with 22.
However the biggest issue to me is that you will might not be able to receive calls from any normal Local PSTN/ Mobile phone at present unlike services like Vonage etc defeating the whole concept because the mtnl website is still unclear about the modalities. Hopefully they are talking about local mobiles and landlines and not International ones so as to protect their core business.
Who is it for ?
Generally it will be most useful to people like Senior Citizens, and middle aged people with children living in foreign countries , including the techno phobics and people who have a huge ISD bill, and ones who want a dedicated international phone line.
As of now i haven’t checked out the Mtnl system or taken a demo so my opinion stands at Neutral .