n Dial-up Modems: The 56k internal modem is more popular today, though power users still prefer external modems. The external modems are also more reliable and offer better download speeds. Besides, if the user is not confident about opening up the machine, it is better to stick to an external modem.

n Driver Availability: Check if the modem driver is available on the vendor website.

n Cable Modems—Standards Compliance: The cable modem must comply with the Data Over Cable Service Interface Specification (DOCSIS) 1.0 standards.

n DSL Modems: Standards Compliance: The modem should support industry standards like G.lite and ITU G.dmt.

Compatibility: Most of the types of DSL technologies like DSL, HDSL, VDSL, and RADSL are incompatible with one another. It is therefore important that the user uses the same type of DSL technology as the service provider.