User's Manual

Reference Manual for the NETGEAR ProSafe VPN Client
Glossary
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DNS
Short for Domain Name System (or Service), an Internet service that translates domain names into IP
addresses.
Because domain names are alphabetic, they're easier to remember. The Internet however, is really based on
IP addresses. Every time you use a domain name, therefore, a DNS service must translate the name into the
corresponding IP address. For example, the domain name www.example.com might translate to
198.105.232.4. The DNS system is, in fact, its own network. If one DNS server doesn't know how to
translate a particular domain name, it asks another one, and so on, until the correct IP address is returned.
Domain Name
A descriptive name for an address or group of addresses on the Internet. Domain names are of the form of a
registered entity name plus one of a number of predefined top level suffixes such as .com, .edu, .uk, etc. For
example, in the address mail.NETGEAR.com, mail is a server name and NETGEAR.com is the domain.
DSL
Short for digital subscriber line, but is commonly used in reference to the asymmetric version of this
technology (ADSL) that allows data to be sent over existing copper telephone lines at data rates of from 1.5
to 9 Mbps when receiving data (known as the downstream rate) and from 16 to 640 Kbps when sending data
(known as the upstream rate).
ADSL requires a special ADSL modem. ADSL is growing in popularity as more areas around the world
gain access.
DSLAM
DSL Access Multiplexor. The piece of equipment at the telephone company central office that provides the
ADSL signal.
Dynamic Host Configuration Protocol.
DHCP is a protocol for assigning dynamic 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 simplifies network administration because the software tracks IP addresses
rather than requiring an administrator to manage the task. A new computer can be added to a network
without the hassle of manually assigning it a unique IP address.
E
ESP
Encapsulating Security Payload.
Ethernet
A LAN specification developed jointly by Xerox, Intel and Digital Equipment Corporation. Ethernet
networks transmit packets at a rate of 10 Mbps.