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A static IP is a number (in the form of a dotted quad, i.e.. - 192.168.001.005) that is assigned
to a computer by an Internet Service Provider (ISP) or by a Companies IT/MIS (Information
Technology / Management Information Systems) Department, to be its permanent address on
the Internet. Computers use IP addresses to locate and talk to each other on the Internet, much
the same way people use phone numbers to locate and talk to one another on the telephone.
It would be simple if every computer that connects to the Internet could have its own static IP
number, but when the Internet was first conceived, the architects didn't foresee the need for an
unlimited number of IP addresses. Consequently, there are not enough IP numbers to go around.
Dynamic IP address
Is a temporary IP address, which many Internet service providers use to limit the number of static IP
addresses they allocate, and economize on the remaining number of IP addresses they
possess by temporarily assigning an IP address to a requesting Dynamic Host Configuration
Protocol (DHCP) computer from a pool of IP addresses.
Requesting DHCP computers receive a dynamic IP address (think temporary phone number) for
the duration of that Internet session or for some other specified amount of time. Once the user
disconnects from the Internet, their dynamic IP address goes back into the IP address pool so it
can be assigned to another user. Even if the user reconnects immediately, odds are they will not
be assigned the same IP address from the pool. To keep our telephone analogy going,
using a dynamic IP address is similar to using a pay phone. Unless there is a reason to receive
a call, the user does not care what number he or she is calling from.
Dynamic Host Configuration Protocol (DHCP) is a communications protocol that lets network
administrators manage centrally and automate the assignment of Internet Protocol (IP)
addresses in an organization's network. Using the Internet Protocol, each machine
that can connect to the Internet needs a unique IP address. When an organization sets up
its computer users with a connection to the Internet, an IP address must be assigned to each
machine. Without DHCP, the IP address must be entered manually at each computer and,
if computers move to another location in another part of the network, a new IP address must
be entered. DHCP lets a network administrator supervise and distribute IP addresses from
a central point and automatically sends a new IP address when a computer is plugged into a
different place in the network.
A gateway is a network point that acts as an entrance to another network. On the Internet,
a node or stopping point can be either a gateway node or a host (end-point) node.
Both the computers of Internet users and the computers that serve pages to
users are host nodes. The computers that control traffic within your company's network or
at your local Internet service provider (ISP) are gateway nodes.
A mask is used to determine what subnet an IP address belongs to. An IP address has two components,
the network address and the host address.
Subnetting enables the network administrator to further divide the host part of the address into two or
more subnets.
L:\tekcentr\CACTrain\SPS_ntwk
Definition of Network Terms
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10/16/2001
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