The latest future phones would be by the means of using the wireless network which is available to us for free and connecting it via our mobile phone to make a free call via the protocol.
Some may think it is impossible but certain educational institutions have already taken a step further on about this technology to enable the students to use free mobile phones calling while during at the campus.
WiFi phone services can be divided broadly into two categories:
a) Mobile phones that use a wireless network to connect to a VoIP service such as Skype or Vonage,
b) Dual-mode phones that have the capability to run over both wireless networks and a cellular network.
The goal of both of these approaches is the Holy Grail of fixed mobile convergence, which brings mobile and land line services together into a single device.
What is the protocol used?
Mobile VoIP or simply mVoIP is an extension of mobility to a Voice over IP network used in this technology.
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.
What is a WiFi Phone?
These hybrid phones are built to allow users to connect using a local wireless access point (WAP) for Internet usafe and seamlessly switch over to a cell phone network whenever they want to make a phone call. This will result in a greater flexibility for mobile phones communications besides the potential cost savings gained by moving the call minutes that would be counted in a cheap cell phone plan onto the Internet.
The WiFi phone has all the same features as a regular mobile phone. With normal mobile phones, you can make calls,send text messages, receive voice mails and also access the Internet. The WiFi phone has greater data retrieval capabilities and wider Internet access.
For universities or bigger organizations that subscribes to a local Internet Service Provider (ISP) for their wired network, the wireless WiFi zone can easily be created as a plus and then by adapting the WiFi technology, will enable all the staffs and students to use their mobile phones for roaming in the campus area and make free calls.
This can only be succeed with a wide wireless roaming capacity by the university IT department. This technology however is only available for those using smartphones and can connect to the university’s wireless network.
Potential Involved?
Mobile VoIP will require a compromise between economy and mobility. For example, Voice over Wi-Fi offers potentially free service but is only available within the coverage area of a Wi-Fi Access Point. High speed services from mobile operators using EVDO rev A or HSDPA may have better audio quality and capabilities for metropolitan-wide coverage including fast handoffs among mobile base stations, yet it will cost more than the typical Wi-Fi-based VoIP service.
Mobile VoIP will become an important service in the coming years as device manufacturers exploit more powerful processors and less costly memory to meet user needs for ever-more ‘power in their pocket’. Smartphones in mid-2006 are capable of sending and receiving email, browsing the web (albeit at low rates) and in some cases allowing a user to watch TV. Juniper research predicts that mobile VoIP users will exceed 100 million by 2012 and InStat projects 288 million subscribers by 2013.[1]
The challenge for the mobile operator industry is to deliver the benefits and innovations of IP without losing control of the network service. Users like the Internet to be free and high speed without extra charges for visiting specific sites. Such a service challenges the most valuable service in the telecommunications industry — voice — and threatens to change the nature of the global communications industry.
