User's Manual

cabling systems (wires, junctions, and connectors) in terms of the data rates

that they can sustain. CAT 5 cable has a maximum throughput of 100 Mbps and

is usually utilized for 100BaseTX networks.

CAT 5e - The additional cabling performance parameters of return loss and far-

end crosstalk (FEXT) specified for 1000BASE-T and not specified for

10BASE-T and 100BASE-TX are related to differences in the signaling imple-

mentation. 10BASE-T and 100BASE-TX signaling is unidirectional-signals

are transmitted in one direction on a single wire pair. In contrast, Gigabit

Ethernet is bi-directional-signals are transmitted simultaneously in both direc-

tions on the same wire pair; that is, both the transmit and receive pair occupy

the same wire pair.

CSMA/CA (Carrier Sense Multiple Access/Collision Avoidance) - In local

area networking, this is the CSMA technique that combines slotted time-divi-

sion multiplexing with carrier sense multiple access/collision detection

(CSMA/CD) to avoid having collisions occur a second time. This works best if

the time allocated is short compared to packet length and if the number of sit-

uations is small.

Data Packet - One frame in a packet-switched message. Most data communi-

cations is based on dividing the transmitted message into packets. For example,

an Ethernet packet can be from 64 to 1518 bytes in length.

Default Gateway - The routing device used to forward all traffic that is not

addressed to a station within the local subnet.

DHCP (Dynamic Host Configuration Protocol) - A protocol that lets network

administrators manage centrally and automate the assignment of Internet

Protocol (IP) addresses in an organization's network. Using the Internet's set of

protocol (TCP/IP), each machine that can connect to the Internet needs a

unique IP address. When an organization sets up its computer users with a con-

nection to the Internet, an IP address must be assigned to each machine.

Without DHCP, the IP address must be entered manually at each computer and,

if computers move to another location in another part of the network, a new IP

address must be entered. DHCP lets a network administrator supervise and dis-

tribute IP addresses from a central point and automatically sends a new IP

address when a computer is plugged into a different place in the network.

DHCP uses the concept of a "lease" or amount of time that a given IP address

will be valid for a computer. The lease time can vary depending on how long a

user is likely to require the Internet connection at a particular location. It's espe-

Instant Wireless

Series

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