50 V85 Desktop VoIP Phone User Guide
YML772 Rev1
CO Central Office A circuit switch that terminates all the local access
lines in a particular geographic serving area; a physical building
where the local switching equipment is found. xDSL lines running
from a subscriber’s home connect at their serving central office.
DHCP Dynamic Host Configuration Protocol DHCP automates address
assignment and management. When a computer connects to the
LAN, DHCP assigns it an IP address from a shared pool of IP
addresses; after a specified time limit, DHCP returns the address to
the pool.
DHCP relay Dynamic Host Configuration Protocol relay. A DHCP relay is a
computer that forwards DHCP data between computers that request
IP addresses and the DHCP server that assigns the addresses. Each
of the ADSL modem’s interfaces can be configured as a DHCP relay.
See DHCP.
DHCP server Dynamic Host Configuration Protocol server. A DHCP server is
a computer that is responsible for assigning IP addresses to the
computers on a LAN. See DHCP.
digital Of data, having a form based on discrete values expressed as binary
numbers (0’s and 1’s). The data component in DSL is a digital
signal. See also analog.
DNS Domain Name System. The DNS maps domain names into IP
addresses. DNS information is distributed hierarchically throughout
the Internet among computers called DNS servers. When you start to
access a web site, a DNS server looks up the requested domain name
to find its corresponding IP address. If the DNS server cannot find
the IP address, it communicates with higher-level DNS servers to
determine the IP address. See also domain name.
domain name A domain name is a user-friendly name used in place of its
associated IP address. For example, www.globespan. net is the
domain name associated with IP address 209.191.4.240. Domain
names must be unique; their assignment is controlled by the Internet
Corporation for Assigned Names and Numbers (ICANN). Domain
names are a key element of URLs, which identify a specific file at a
web site, e.g., http://www.globespan.net/index.html. See also DNS.
download To transfer data in the downstream direction, i.e., from the Internet
to the user.
DSL Digital Subscriber Line A technology that allows both digital data
and analog voice signals to travel over existing copper telephone
lines.
Ethernet The most commonly installed computer network technology, usually
using twisted pair wiring. Ethernet data rates are 10 Mbps and 100
Mbps. See also BASE-T,100BASE-T, twisted pair.
Filtering To screen out selected types of data, based on filtering rules.
