User manual

Chapter 7: Glossary
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Chapter 7
Glossary
ARP (Address Resolution Protocol )
ARP is a TCP/IP protocol for mapping an IP address to a physical machine address that is
recognized in the local network, such as an Ethernet address.
A host wishing to obtain a physical address broadcasts an ARP request onto the TCP/IP
network. The host on the network that has the IP address in the request then replies with
its physical hardware address.
Inverse ARP (In-ARP), on the other hand, is used by a host to discover its IP address. In
this case, the host broadcasts its physical address and a RARP server replies with the host's
IP address.
DHCP (Dynamic Host Configuration Protocol)
When operates as a DHCP server, the ADSL Router assign IP addresses to the client PCs on
the LAN. The client PCs “leases” these Private IP addresses for a user-defined amount of
time. After the lease time expires, the private IP address is made available for assigning to
other network devices.
The DHCP IP address can be a single, fixed public IP address, an ISP assigned public IP
address, or a private IP address.
If you enable DHCP server on a private IP address, a public IP address will have to be
assigned to the NAT IP address, and NAT has to be enabled so that the DHCP IP address
can be translated into a public IP address. By this, the client PCs are able to access the
Internet.
LAN (Local Area Network) & WAN (Wide Area Network)
A LAN is a computer network limited to the immediate area, usually the same building or
floor of a building. A WAN, on the other hand, is an outside connection to another network
or the Internet.
The Ethernet side of the ADSL Router is called the LAN port. It is a twisted-pair Ethernet
10Base-T interface. A hub can be connected to the LAN port. More than one computers,
such as server or printer, can be connected through this hub to the ADSL Router and
composes a LAN.
The DSL port of the ADSL Router composes the WAN interface, which supports PPP or RFC
1483 connecting to another remote DSL device.