Mobile VoIP

Mobile VoIP or simply mVoIP is an extension of mobility to a Voice over IP network. VoIP is the latest advancement in Mobile phone communication and VoIP technology designed for active cell phone users and people on the go who want to make cheap mobile phone calls and incorporate all the benefits of VoIP. Mobile VoIP calls are made possible by VoIP Service Providers who take signals on a 3G, WiMax or WiFi network and transmit that signal into voice data.  VoIP service providers require users to download their software onto a mobile device similar to what is available on the famous iPhone. Once the software is downloaded and integrated with the mobile phone a user can then expect to enjoy benefits.like SIP messaging which can provide email messaging and robust media support directly to their cell phone. Innovative companies are designing programs that make VoIP calls easy, sometimes free and full of convenient features.


Mobile VoIP relies on two main technologies:
UMA: The Unlicensed Mobile Access Generic Access Network, designed to allow VoIP to run over the GSM cellular backbone.
SIP: The standard used by most VoIP services, and now being implemented on mobile handsets.


There are several methodologies by which a mobile handset can be integrated into a VoIP network. One implementation turns the mobile device into a standard SIP client, which then uses a data network to send and receive SIP messaging, and to send and receive RTP for the voice path. This methodology of turning a mobile handset into a standard SIP client requires that the mobile handset support, at minimum, high speed IP communications. In this application, standard VoIP protocols (typically SIP) are used over any broadband IP-capable wireless network connection such as EVDO rev A (which is symmetrical high speed — both high speed up and down), HSDPA, WiFi or WiMAX.


Another implementation of mobile integration uses a softswitch like gateway to bridge SIP and RTP into the mobile network's SS7 infrastructure. In this implementation, the mobile handset continues to operate as it always has (as a GSM or CDMA based device), but now it can be controlled by a SIP application server which can now provide advanced SIP based services to it. Several vendors offer this kind of capability today.Mobile VoIP will require a compromise between economy and mobility.