SonicWALL TZ 170 SP Getting Started Manual page 37

Glossary of Networking Terms
Default Gateway - A device on an internetwork that forwards packets to another network.
DHCP - Dynamic Host Configuration Protocol allocates IP addresses to computers on the
network automatically without assigning a computer a static (fixed) IP address.
DNS - Domain Name System, a hierarchical naming system that resolves a domain name
with its associated IP address. A DNS server looks up the name of a computer and finds
the corresponding IP address. This allows users to access hosts using friendly text-
based names instead of IP addresses. These names are called fully qualified domain
names (FQDN).
IP Address - Internet Protocol Address, a 32 bit number that identifies a computer or other
resource on the Internet or on any TCP/IP network. The number is usually expressed as
four numbers from 0 to 255 separated by periods, for example, 172.16.31.254.
LAN - A Local Area Network is typically a group of computers located at a single location, and
is commonly based on the Ethernet architecture.
NAT - Network Address Translation, An internet standard that allows your local network to
use private IP addresses, which are not recognized on the Internet. The IP address used
for the router is the only routable IP address. The computers behind the NAT can access
the Internet through the router, but Internet users cannot access the computers behind
the router.
Packet - A unit of information transmitted over the internet or within any TCP/IP network.
Packets have a header, which contains information about the source, destination, and
protocol to be used for the data, and a body, which contains the data being transmitted.
PPPoE - The Point to Point Protocol over Ethernet supports the transmission of network
packets over an analog phone line.
Private IP Address - An IP address for a resource in your network that is not known or
published outside the zone (for example LAN) where it is located.
Public IP Address - An IP address for a resource in your network that is published outside
your network to the WAN.
Router - A device that routes data between networks through IP address information in the
header of the IP packet. A router forwards packets to other routers until the packets reach
their destination. The Internet is the largest example of a routed network.
Subnet - A portion of a network. Each subnet within a network shares a common network
address and is uniquely identified by a subnetwork number.
Subnet Mask - A 32-bit number used to separate the network and host sections of an IP
address. A subnet mask subdivides an IP network into smaller pieces. An example of a
subnet mask might be 255.255.255.248 for subnet with only eight IP addresses.
TCP/IP - Transmission Control Protocol/Internet Protocol is the basic communication protocol
of the Internet. It supports sending information in packets, and identifies each device with
a unique numeric IP address.
VPN - A Virtual Private Network is a virtual network that encrypts data and sends it privately
over the Internet to protect sensitive information.
WAN - A Wide Area Network is a geographically distributed network composed of multiple
networks joined into a single large network. The Internet is a global WAN.
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