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Challenge Handshake Authentication Protocol. An alternative protocol that uses a challenge/response
technique instead of sending passwords over the wire.
Collision
Interference resulting from two network devices sending data at the same time. The network detects the
collision of the two transmitted packets and discards both of them.
Coverage
The region within which a paging receiver can reliably receive the transmission of paging signals.
Coverage Area
The geographical area that can be served by a mobile communications network or system.
Coverage Hole
An area within the radio coverage footprint of a wireless system where the RF signal level is below the
design threshold. Physical obstructions such as buildings, foliage, hills, tunnels, and indoor parking
garages are usually the cause of coverage holes.
Cyclic Redundancy Check (CRC)
A common technique for detecting data transmission errors.
Dynamic Host Configuration Protocol (DHCP)
A protocol that assigns temporary IP addresses automatically to client stations logging onto an IP
network, so the IP addresses do not have to be assigned manually. The ENH210EXT contains an internal
DHCP server that automatically allocates IP address using a user-defined range of IP addresses.
Dead Spot
An area within the coverage area of a WLAN where there is no coverage or transmission falling off.
Electronic interference or physical barriers such as hills, tunnels, and indoor parking garages are usually
the cause of dead spots. See also coverage area.
802.11
A category of WLAN standards defined by the Institute of Electrical and Electronics Engineers (IEEE).
802.11a
An IEEE standard for WLANs that operate at 5 GHz, with data rates up to 54 Mbps.
802.11n
An IEEE standard for WLANs that operates at 2.4 GHz, with 5GHz band as option and data rate of 300
Mbps. The new standard also raises the encryption bar to WPA2. The 40 HT option can be added to
increase the data rate.
Encryption
Translates data into a secret code to achieve data security. To read an encrypted file, you must have a
secret key or password for decryption. Unencrypted data is referred to as plain text; encrypted data is
referred to as cipher text
