User's Guide

3e-531AP Wireless Access Point Glossary
29000125-001 C G-a
Glossary
802.11
802.11 refers to a family of specications developed by the IEEE for wireless LAN technol-
ogy. 802.11 species an over-the-air interface between a wireless client and a base station
or between two wireless clients. The IEEE accepted the specication in 1997.
802.11b (also referred to as 802.11 High Rate or Wi-Fi)
802.11b is an extension to 802.11 that applies to wireless LANs and provides 11 Mbps
transmission (with a fallback to 5.5, 2 and 1 Mbps) in the 2.4 GHz band. 802.11b uses only
DSSS. 802.11b was a 1999 ratication to the original 802.11 standard, allowing wireless
functionality comparable to Ethernet.
Access Point
An access point is a gateway set up to allow a group of LAN users access to another group
or a main group. The access point doesn’t use the DHCP server function and therefore ac-
cepts IP address assignment from the controlling network.
Bridge
A device that connects two local-area networks (LANs), or two segments of the same LAN
that use the same protocol, such as Ethernet or Token-Ring.
Certication Authority
An entity responsible for establishing and vouching for the authenticity of public keys
belonging to users (end entities) or other authorities. Activities of a certication author-
ity can include binding public keys to distinguished names through signed certicates,
managng certicate serial numbers, and certicate revocation.
DHCP
Short for Dynamic Host Conguration Protocol, DHCP is a protocol for assigning dy-
namic IP addresses to devices on a network. With dynamic addressing, a device can have
a different IP address every time it connects to the network. In some systems, the device’s
IP address can even change while it is still connected. DHCP also supports a mix of
static and dynamic IP addresses. Dynamic addressing simplies network administration
because the software keeps track of IP addresses rather than requiring an administrator to
manage the task. This means that a new computer can be added to a network without the
hassle of manually assigning it a unique IP address. Many ISPs use dynamic IP addressing
for dial-up users.
DMA
An abbreviation of Direct Memory Access, DMA is a technique for transferring data from
main memory to a device without passing it through the CPU. Computers that have
DMA channels can transfer data to and from devices much more quickly than computers
without a DMA channel can. This is useful for making quick backups and for real-time
applications.
DMZ
A DMZ (Demilitarized Zone) is used by a company that hosts its own Internet services. It
sits between the Internet and the internal network. It is a combination of rewalls and bas-