How is 4G standard defined currently?

4G network also known as “beyond 3G” or “fourth-generation” wireless technology refers to the entirely new evolution with a complete 3G replacement in wireless communications. The 4G network is based on IP packet switched networks rather than the previous generations where 1G and 2G are circuit data. 4G has highest data transmission speed than previous generations wireless technology. The 4G network, assures voice over IP(Internet Protocol), data and high-quality multimedia in real-time (“streamed”) form at all time anywhere. The 4G network is not currently implemented. Many wireless carriers like Sprint are trying to sell the customers the idea that 4G is currently available. The 4G standards are based on two technologies.
These technologies are LTE (Long Term Evolution) standardized by 3GPP (Third Generation Partnership Projects) and the IEEE 802.16, an advanced air interface with data rates of 100 Mbit/s at mobile & 1 Gbit/s at stationary.
Sprint offers a 3G/4G connection plan, currently available in select cities in the United States. Sprint 4G covers more than 30 million people and expects to have up to 120 million people covered by the end of 2010. Sprint currently offers 4G services in 27 markets, including Atlanta, Baltimore, Chicago, Dallas, Las Vegas, Philadelphia, Portland, Ore., San Antonio and Seattle (www.sprint.com/4G). HTC Corporation (HTC) is one of the fastest growing companies in the mobile phone industry. HTC creates innovative smart phones that better serve the lives and needs of individuals. HTC announced the first 3G/4G Android handset availability this summer (www.htc.com). Verizon Wireless announced their plan to joint venture with the Vodafone group to transition their networks to 4G standards LTE by the end of 2010. Currently, Verizon covers over 80 percent of the U.S. population with its high-speed 3G network. Bell Canada and Telus, major Canadian carriers, announced to cooperate together to transition their networks building towards a 4G standards LTE in Canada.
Sprint released Single-mode devices and dual-mode devices for 4G coverage (4G network defined by Sprint alone). Single-mode devices provide the end user to access the 4G network, where available. This device can be used on computers or laptops with an appetite for videos, games, email and pictures. The device also can be used with a hotspot accessory and share a connection at the office or at home. The Sprint 4G Desktop Modem CPEi25150 by Motorola allows the client to connect 4G without complicated installation. The procedures simply require the user to plug the device into the computer or wifi router. It is a great solution when the end user needs to get a reliable Internet connection. Dual-mode device offer the customers to access the Sprint 3G network, and 4G network where available. This device allows 4G connections with up to 5 WiFi devices like laptop, cameras, and portable game and music players. One can obtain coverage of the 3G Sprint network if travel outside of 4G coverage.
The 4G network standards vary from everybody however 4G standardization is expected to be included in 3GPP soon. Currently, The International Telecommunication Union, Radiocommunicatio (ITU-R) also stated that the 4G network requirement was supported by the peak data rate 1Gbit/s (http://en.wikipedia.org/wiki/LTE_Advanced).