ZyXEL Communications Prestige 643 User Manual page 176

Prestige 643 ADSL Router
Client
CPE
crossover Ethernet
cable
Data Filtering
Device Filter Rules
DHCP
DNS
Domain Name
DRAM
DSL
R
A software program that is used to contact and obtain data from a Server software
program on another computer. Each Client program is designed to work with one or
more specific kinds of Server programs and each Server requires a specific kind of
Client. A Web Browser is a specific kind of Client.
Customer Premises Equipment: that portion of the ADSL system residing within the
customer's premises.
A cable that wires a pin to its opposite pin, for example, RX+ is wired to TX+. This
cable connects two similar devices, for example, two data terminal equipment (DTE)
or data communications equipment (DCE) devices.
Data filtering screens the data to determine if the packet should be allowed to pass.
Data filters are divided into incoming and outgoing filters, depending on the
direction of the packet relative to a port. Data filtering can be applied on either the
WAN side or the LAN side.
For Device rules, the Prestige treats a packet as a byte stream as opposed to an IP or
IPX packet. You specify the portion of the packet to check with the Offset (from 0)
and the Length fields, both in bytes.
Dynamic Host Configuration Protocol automatically assigns IP addresses to clients
when they log on. DHCP centralizes IP address management on central computers
that run the DHCP server program. DHCP leases addresses for a period of time
which means that addresses are made available to assign to other systems.
Domain Name System links names to IP addresses. When you access Web sites on
the Internet, you can type the IP address of the site or the DNS name. When you type
a domain name in a Web browser, a query is sent to the primary DNS server defined
in your Web browser's configuration dialog box. The DNS server converts the name
you specified to an IP address and returns this address to your system. From then on,
the IP address is used in all subsequent communications.
The unique name that identifies an Internet site. Domain Names always have two or
more parts, separated by dots. The part on the left is the most specific and the part on
the right is the most general.
Dynamic RAM that stores information in capacitors that must be refreshed
periodically.
Digital Subscriber Line technologies enhances the data capacity of the existing
twisted-pair wire that runs between the local telephone company switching offices
and most homes and offices. There are actually seven types of DSL service, ranging
in speeds from 16 Kbits/sec to 52 Mbits/sec. The services are either symmetrical
Glossary