Fast Ethernet

See 100Base-T.


Brand name for Verizon’s fiber optic Internet service. Fiber optic lines transmit data as pusles of light instead of pulses of electricity; they are incredibly fast, but also much more expensive than traditional copper lines. Verizon Fios service requires fiber optic lines to be run directly to homes and businesses, which can cost as much as $1000 per address. As a result, Verizon is currently only offering the service as a trial to a few select communities in the United States.


A system that actively protects a computer or network of computers from intrusion. Firewalls are available both as software programs and stand-alone devices.

There are two basic categories of protection:

  • Inbound - checks requests arriving from outside parties. Protects from port scanning, hacker attacks, and more. The basis of all firewalls.
  • Outbound - checks transmissions being sent to outside parties. Protects from trojan horse programs. Available on some newer firewalls, including the excellent ZoneAlarm.

Note that most routers are not firewalls because their protection is inactive. They do not perform packet-sniffing or any other type of security check; they simply ignore/discard unknown requests. This nevertheless provides a fairly good amount of protection.


A standardized high-speed interface for connecting peripherals to computers.

Also known as IEEE 1394, iLink, and FireWire 400. It can transmit data at 400 Mbps and does not require the user to reboot to install new devices. It was developed in the late 1990s by Apple Computer as a replacement for the archaic SCSI standard. Because it is expensive, however, its use has been mostly limited to video transfer and other high-end applications.

FireWire 800 (IEEE 1394b) was recently introduced, offering speeds of 800 Mbps while maintaing backward compatibility with FireWire 400 devices.


Software that supports and instructs the operation of a hardware device.

In the context of Internet connection sharing, routers have firmware that can be periodically updated to squash bugs and add new features.


File Transfer Protocol. The protocol used on the Internet for sending files.