Reference Manual for the 54 Mbps Wireless Travel Router WGR101
B-2
Network Basics
February 2005 (202-10034-03)
Routing Information Protocol
One of the protocols used by a router to build and maintain a picture of the network is the Routing
Information Protocol (RIP). Using RIP, routers periodically update one another and check for
changes to add to the routing table.
The WGR101 wireless travel router supports both the older RIP-1 and the newer RIP-2 protocols.
Among other improvements, RIP-2 supports subnet and multicast protocols. RIP is not required
for most home applications.
IP Addresses and the Internet
Because TCP/IP networks are interconnected across the world, every machine on the Internet must
have a unique address to make sure that transmitted data reaches the correct destination. Blocks of
addresses are assigned to organizations by the Internet Assigned Numbers Authority (IANA).
Individual users and small organizations may obtain their addresses either from the IANA or from
an Internet service provider (ISP). You can contact IANA at www.iana.org.
The Internet Protocol (IP) uses a 32-bit address structure. The address is usually written in dot
notation (also called dotted-decimal notation), in which each group of eight bits is written in
decimal form, separated by decimal points.
For example, the following binary address:
11000011 00100010 00001100 00000111
is normally written as:
195.34.12.7
The latter version is easier to remember and easier to enter into your computer.
In addition, the 32 bits of the address are subdivided into two parts. The first part of the address
identifies the network, and the second part identifies the host node or station on the network. The
dividing point may vary depending on the address range and the application.
There are five standard classes of IP addresses. These address classes have different ways of
determining the network and host sections of the address, allowing for different numbers of hosts
on a network. Each address type begins with a unique bit pattern, which is used by the TCP/IP
software to identify the address class. After the address class has been determined, the software
can correctly identify the host section of the address. The follow figure shows the three main
address classes, including network and host sections of the address for each address type.
