In telecommunication systems, a generic access network (GAN) is used by cellular device users to connect and interact with other types of communication devices. GAN protocols primarily evolved for wireless communication systems, allowing mobile phones to perform functions seamlessly between wireless local area networks (WLANs) and wide area networks (WANs) without interrupting the communication session. Modern GAN technology permits a subscriber to interact via voice, data, IP multimedia subsystem and Session Initiation Protocol (SIP) applications. Using GAN technology, a cell phone subscriber can communicate by voice, data and multimedia. As GAN technology is implemented, cellular telephone subscribers can expect improved coverage, the ability to use a single phone set for all their voice communications and perhaps cheaper rates with a single bill for Internet and voice communications.
Prior to 2005, a generic access network was commercially known as unlicensed mobile access (UMA)..
The Generic Access Network (GAN) is an evolving wireless communications system in which mobile phone sets function seamlessly between local area networks (LANs) and wide-area networks (WANs). Using GAN technology, a cell phone subscriber can communicate by voice, data and multimedia. As GAN technology is implemented, cellular telephone subscribers can expect improved coverage, the ability to use a single phone set for all their voice communications and perhaps cheaper rates with a single bill for Internet and voice communications. Main application of this GAN/UMA is the Dual-mode Handset service. History of Generic Access Network
In September 2004, the participating companies published the initial UMA specifications and formally introduced them to the 3rd Generation Partnership Project (3GPP) standards body. In April 2005, an unprecedented eight months later, the UMA specifications were incorporated into the 3GPP release 6 specifications. While referred to as "Generic Access Network" or GAN, within the 3GPP specifications. In mid 2006, mobile operators around the world began announcing their intention to deploy dual-mode handset (DMH)-based UMA services. Throughout 2007, there were constant announcement of new UMA-enabled dual-mode phones to support the commercial service offers. In early 2008, the first commercial UMA-based fixed line VoIP service appeared as well as the first UMA-enabled softmobile client. Problems of Generic Access Network
Subscribers must upgrade to Wi-Fi/UMA enabled handsets to take advantage of the service. Calls may be more prone to disconnect when the handset transitions from Wi-Fi to the standard wireless service and vice versa (because the handset moved out or within the Wi-Fi's range). How much this is a problem may vary based on which handset is used. The UMA may use different frequency that is more prone to some types of interference. Some setup may be required to provide connection settings (such as authentication details) before advantages may be experienced. This may take time for subscribes and require additional support to be provided. The costs of support may be for more than the wireless phone company: network administrators may be asked to help a user enter appropriate settings into a phone (that the network administrator may know little about). The phones that support multiple signals (both the UMA/Wi-Fi and the type of signal used by the provider's towers) may be more expensive, particularly to manufacture, due to additional circuitry/components required. This uses the resources of the network providing the Wi-Fi signal (and any indirect network that is then utilized when that network is used). Bandwidth is used up. Some types of network traffic (like DNS and IPsec-encrypted) need to be permitted by the network, so a decision to support this may impose some requirement(s) regarding the network's security (firewall) rules.
Significance of Generic Access Network...