A cellular router is a portable device providing shared Internet access through a cellular gateway. A standard wireless interface makes it easy for computers, cell phones, personal digital assistants (PDAs) and other network-enabled products to share the connection. The difference between a cellular router and a traditional router is that the latter obtains Internet access through cable, telephone or fiber optic lines rather than cell towers. This enables a cellular router to create an Internet gateway on the move, such as on a moving train, or in an area lacking landlines or an alternate means of access.
The ability to move while remaining connected to the Internet is a significant advantage of cellular broadband. Most people already enjoy mobile broadband on Web-enabled cell phones. A cellular router takes this convenient access and creates a Local Area Network (LAN) for all of your mobile or portable wireless devices. It can be used as a primary Wide Area Network (WAN) link, or in situations where traditional access is unavailable or is not cost-effective to implement. It can also provide a backup network, should the primary line-based network fail.
A cellular router must be compatible with the particular carrier you wish to use. The routers are sold by carriers and also by third parties. Different models support one or more cellular technologies or protocols, such as Code Division Multiple Access (CDMA/CDMA2000) and Global Systems for Mobile communications (GSM). These technologies each have their own continually evolving standards, including Enhanced Data Rates for GSM Evolution (EDGE) known as a third generation GSM or GSM 3G; and Evolution-Data Optimized (EV-DO) the CDMA2000 3G standard. Developing fourth generation (4G) capabilities are providing even faster data speeds for both types of standards.
A cellular router can come in an integrated or modular configuration. Integrated routers have the modem already built-in. Modular routers feature USB and ExpressCard® ports for attaching a separate cellular modem. The modem is what actually communicates with the cellular towers, while the router directs traffic on the LAN between connected devices, and between the LAN and WAN, or the local network and the Internet. Most cellular routers feature Ethernet ports for optional wired networking. Built-in firewalls and the ability to encrypt traffic between the router and its clients or connected devices is also standard.
A cellular router can cost anywhere from about $75 US Dollars (USD) to several hundred dollars, but models aimed towards the average end user are generally under $200 USD. While cellular broadband is extremely convenient, it also remains the most expensive type of Internet access. Carriers will often give special rates to existing clients with cell service, but broadband access will be a separate and additional monthly charge. Unlike landline broadband, cellular broadband enforces bandwidth caps to keep data hogs from slowing the network. For everyday needs, the caps should not be a problem, but heavy downloaders will want to hang on to their cable or digital subscriber line (DSL) plans.