Anyone shopping for a modem is faced with a bewildering array of choices. There are dial-up, cable and ISDN modems with varying capabilities and dozens of brands. Modems can be external devices connected wirelessly or plugged into serial or USB ports or they can be PC cards or adapter cards that plug into a standard PC or laptop.

Shopping for a Modem

Dial-up modems are classified according to a number of modulation standards. These include standards for transmission speed, data compression and fax capabilities. Currently V.92 is the fastest transmission protocol capable of 56k transmission speed. It offers a shorter connection negotiation or "handshake" interval and includes an "on hold" feature to reduce dropped connections.

Standard Cable TV Connections

Cable modems enable high speed or broadband access to the Internet via a standard TV cable outlet. They are internal or external devices connected wirelessly or via standard Ethernet network cable connections. Routers can be connected to the cable modem to enable multiple computers equipped with network cards to access the Internet simultaneously. USB ports can also be used to connect computers to cable modems, but only a single computer per cable outlet can be connected in this way.

It is easy to understand why consumers are rapidly turning to cable modems for internet access. Cable modems are fast and enable users to have persistent or "always on" internet connections. Persistent connections combined with high transmission speeds enable users to run advanced applications such as VoIP or Internet Telephony. Web servers can also be run from cable connections if permitted by the internet service providers terms of service.