User Manual

including Ethernet.

Direct-Sequence Spread Spectrum (DSSS) and Frequency-Hop Spread Spectrum (FHSS): Two

incompatible technologies used in radio transmission.

Extensible Authentication Protocol (EAP): An authentication protocol that supports multiple authentication

methods, such as Kerberos, passwords, or smart cards. Cisco's authentication protocol, LEAP, is based on

EAP, an extension to PPP (Point-to-Point Protocol).

Encryption: Scrambling data so that only the authorized recipient can read it. Usually a key is needed to

decrypt the data.

Extended Service Set IDentifier (ESSID): A type of unique identifier applied to both the AP and the wireless

PC Card that is attached to each packet. This allows the AP to recognize each wireless client and its traffic.

Frequencies: Strike a piano key and you generate a tone. Pick up the tone with a microphone and your tone

turns in to a “vibrating” or “cycling” electronic signal. The rate of vibration depends on the key struck. In

electronics we refer to this rate of vibration as the number of “cycles per second.” The formal term for this

value is Hertz. As we move up in rate, such as in the Broadcast Band, we can use Kilohertz (KHz) to represent

1,000 Hz, or Megahertz (MHz) to represent 1,000,000 Hz. Continuing much further upward, we finally reach

1,000,000,000 Hz, which we can fortunately shorten to a Gigahertz (GHz). These frequencies are the home of

both 802.11a (5 GHz) and 802.11b (2.4 GHz).

Independent Basic Service Set Identifier (IBSSID): Used to identify a wireless network configured to allow

each wireless client to communicate directly with each other without an access point.

Independent Network: A network that provides (usually temporarily) peer-to-peer connectivity without relying

on a complete network infrastructure.

Infrastructure Mode: A wireless network centered around an access point. In this environment, the access

point not only provides communication with the wired network but also mediates wireless network traffic in the

immediate neighborhood.

Institute of Electrical and Electronics Engineers (IEEE): An organization involved in setting computing and

communications standards.

ISM Bands: A series of frequency bands, set aside by the FCC for Industrial, Scientific and Medical

applications. Users of these bands operate equipment on a shared basis, meaning that they must expect, and

accept interference from other legal users. Products manufactured for ISM Band use must be approved by the

FCC, but the user does not have to be licensed. In addition to WLAN, ISM bands support cordless phones,

microwave ovens, baby monitors, toys, ham radio transceivers, and other wireless services.