Page 107 - Handout Computer Network.
P. 107
— Internetwork Packet Exchange (IPX)
— AppleTalk
Figure 5-1 shown a Routed and Routable Protocols
• Routing protocol—Supports a routed protocol by providing mechanisms for sharing routing
information. Routing protocol messages move between the routers. A routing protocol allows
the routers to communicate with other routers to update and maintain tables.
Here are some TCP/IP examples of routing protocols:
— Routing Information Protocol (RIP)
— Interior Gateway Routing Protocol (IGRP)
— Enhanced Interior Gateway Routing Protocol (EIGRP)
— Open Shortest Path First (OSPF)
For a protocol to be routable, it must provide the capability to assign a network number, as well as a
host number, to each individual device.
Some protocols, such as Internetwork Packet Exchange (IPX), only require that an administrator assign
a network number, because they use a host’s Media Access Control (MAC) address for the physical
number.
Other protocols, such as IP, require that a complete address be provided, as well as a network mask.
Both the IP address and network mask are required to have a routed network. A network mask
separates the network and host portions of a 32-bit IP address. IPX uses the MAC address
concatenated with an administrator-assigned network address to create the complete address and
does not use a network mask.
With IP addresses, the network address is obtained by comparing the address with the network mask.
A network mask allows groups of sequential IP addresses to be treated as a single unit. If this grouping
were not allowed, each host would have to be mapped individually for routing. That would not be

