A wireless IP Phone can be described as a sophisticated, next generation mobile IP communication device. The concept of Wireless IP Phone originated due to the spread of Wireless LAN (WLAN) in business organizations.

It integrates the regular IP phone with wireless installations and facilitates parallel voice and data support to enterprise desktops on the same wireless prop. The technology supports not just the standard packet-switch IP telephones but also the traditional circuit-switch PBX (Private Branch Exchange) interfaces. Primarily developed to be used within the offices, it combines the cost-effectiveness of an IP Phone and the convenience of a mobile phone.

Originally the wireless IP Phones were not intended to replace the traditional mobile phones but were meant to be used exclusively within a restricted environment like the premises of a business organization or a house. The earlier models work only through WLAN which has limited geographic application. The range of operation, both indoor and outdoor, of the phone would depend on the capacity of the hardware providing the wireless access and it goes without saying that performance would deteriorate with distance.

The latest models are designed to support both WLAN and public wireless network. Mobile PCs such as laptops and palmtops can be carried anywhere and can run on various applications but they lack the compact portability of cellular phones. Public wireless networks such as cellular phones cover wide geographical areas but have limited data bandwidth. Therefore, the new models of Wireless IP Phones are developed combining the open architecture of laptops and the easy portability of cellular handset so that they can switch to public wireless network after coming out of the purview of WLAN. There will not be any interruption in service during the switch.

The Wireless IP Phone works on battery and needs to be charged just like a regular cellular phone. Older models battery requires greater power; talk time and stand by time are also lower than those offered by a regular cellular phone. But the latest models claim to be on par with regular cellular phones and offer similar features like caller ID, call hold and transfer, conference calls, selectable ring tones, phone book etc.

However, security is the major problem. Signals are broadcast over the air in the wireless system and can be easily intercepted by outsiders who are within the range of reception. Wireless link must be secured to avoid such risks.