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GLOSSARY
6 GLOSSARY
Default Gateway (Router):
Every non-router IP device needs to configure a default
gateway’s IP address. When the device sends out an IP packet, if the destination is
not on the same network, the device has to send the packet to its default gateway,
which will then send it out toward the destination.
DHCP:
Dynamic Host Configuration Protocol. This protocol automatically gives
every computer on your home network an IP address.
DNS Server IP Address:
DNS stands for Domain Name System, which allows
Internet servers to have a domain name (such as www.Broadbandrouter.com) and
one or more IP addresses (such as 19.2.34.45.8.). A DNS server keeps a database
of Internet servers and their respective domain names and IP addresses, so that
when a domain name is requested (as in typing “Broadbandrouter.com” into your
Internet browser), the user is sent to the proper IP address. The DNS server IP
address used by the computers on your home network is the location of the DNS
server your ISP has assigned to you.
DSL Modem:
DSL stands for Digital Subscriber Line. A DSL modem uses your
existing phone lines to transmit data at high speeds.
Idle Timeout:
Idle Timeout is designed so that after there is no traffic to the
Internet for a pre-configured amount of time, the connection will be disconnected.
IP Address and Network (Subnet) Mask:
An Internet Protocol address consists
of a series of four numbers separated by periods, which identifies a single, unique
Internet computer host in an IP network. Example: 19.2.168..2.1 consists of two
portions: the IP network address and the host identifier. The IP address is a 32-bit
binary pattern that can be represented as four cascaded decimal numbers separated
by “.”: aaa.aaa.aaa.aaa, where each “aaa” can be anything from 000 to 255; or as
four cascaded binary numbers separated by “.”: bbbbbbbb.bbbbbbbb.bbbbbbbb.
bbbbbbbb, where each “b” can either be 0 or 1. A network mask is also a 32-bit
binary pattern, and consists of consecutive leading 1’s followed by consecutive
trailing 0’s, such as 11111111.11111111.11111111.00000000. Therefore, sometimes
a network mask can also be described simply as “x” number of leading 1’s. When
both are represented side by side in their binary forms, all bits in the IP address
that correspond to 1’s in the network mask become part of the IP network address,
and the remaining bits correspond to the host ID. For example, if the IP address
for a device is, in its binary form, 11011001.10110000.10010000.00000111, and if
its network mask is 11111111.11111111.11110000.00000000 it means the device’s
network address is 11011001.10110000.10010000.00000000, and its host ID is
00000000.00000000.00000000.00000111. This is a convenient and efficient method
for routers to route IP packets to their destination.
