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A wireless modem is a type of modem which connects to a wireless network instead of to the telephone system. When you connect with a wireless modem, you are attached directly to your wireless ISP (Internet Service Provider) and you can then access the Internet.
Contents
1 Types of devices used
2 History
3 Service Providers
3.1 North America
3.2 Europe
3.3 Asia
3.4 Oceania
4 Device Manufacturers
5 Technologies
6 Account hacking
7 See also
8 References
9 External links
//
Types of devices used
A mobile phone can be used as a wireless modem
Mobile phones, smartphones, and PDAs can be employed as data modems to form a wireless access point connecting a personal computer to the Internet (or some proprietary network). In this use the mobile phone is providing a gateway between the cellular service provider's data network technology and Point-to-Point Protocol (PPP) spoken by PCs. Almost all current mobile phone models support the Hayes command set, a standard method of controlling modems. To the PC, the phone appears like an external modem when connected via serial cable, USB, IrDA infrared or Bluetooth wireless.
An iBurst desktop modem by Kyocera
Wireless FireWire, USB and Serial modems are also used in the Wi-Fi and WiMAX standards, operating at microwave frequencies, to give a laptop, PDA or desktop computer an access point to a network. The modems may be as large as a regular cable modem to as small as a WiFi dongle/USB-stick. If combined with VoIP technology, these computing devices can achieve telephony capability to make and receive telephone calls.
PCMCIA, ExpressCard and Compact Flash modems are also used. These card-modems can also have GPS included. [1]
History
While some analogue mobile phones provided a standard RJ11 telephone socket into which a normal landline modem could be plugged, this only provided slow dial-up connections, usually 2.4 kilobit per second (kbit/s) or less. The next generation of phones, known as 2G (for 'second generation'), were digital, and offered faster dial-up speeds of 9.6kbit/s or 14.4kbit/s without the need for a separate modem. A further evolution called HSCSD used multiple GSM channels (two or three in each direction) to support up to 43.2kbit/s. All of these technologies still required their users to have a dial-up ISP to connect to and provide the Internet access - it was not provided by the mobile phone network itself.
The release of 2.5G phones with support for packet data changed this. The 2.5G networks break both digital voice and data into small chunks, and mix both onto the network simultaneously in a process called packet switching. This allows the phone to have a voice connection and a data connection at the same time, rather than a single channel that has to be used for one or the other. The network can link the data connection into a company network, but for most users the connection is to the Internet. This allows web browsing on the phone, but a PC can also tap in to this service if it connects to the phone. The PC needs to send a special telephone number to the phone to get access to the packet data connection. From the PC's viewpoint, the connection still looks like a normal PPP dial-up link, but it is all terminating on the phone, which then handles the exchange of data with the network. Speeds on 2.5G networks are usually in the 30-50kbit/s range.
3G networks have taken this approach to a higher level, using different underlying technology but the same principles. They routinely provide speeds over 300kbit/s. Due to the now increased internet speed, internet connection sharing via WLAN has become a workable reality. A particularly popular project has been the Stomp Box, which is a router which shares GPRS internet access via WiFi. [2]
A further evolution is the 3.5G technology HSDPA, which has the capacity to provide speeds of multiple Megabits per second.
WiMax has now also been announced, which will allow internet connection sharing over WANs (being region-wide, as opposed to local with WiFi), effectively perhaps eliminating the need of wireless modems. This, of course, only in areas where WiMax is to be introduced (eg cities).
Service Providers
There are competing common carriers broadcasting signal in most nations of the earth. Some of these Cellular networks and the carrier's service plans are:
North America
Canada providers
List of Canadian mobile phone companies
United States providers
T-mobile
AT&T Mobility
Verizon Wireless
Sprint Nextel Corporation
Alltel
Europe
United Kingdom providers
T-mobile
Vodafone
O2 plc
Orange SA
3 (telecommunications)
Spanish providers:
Movistar
Vodafone
...(and so on)
| | GSM Fixed Wireless Phone Features: 1) Supports fax and telephone ports 2) Phone book 3) Intelligent power management 4) Attached.. |
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