Information Technology Reference
In-Depth Information
IP Routing Protocols
List the acronym and full name of the dynamic routing protocols for IP.
RIP
(
Routing Information Protocol
)
■
IGRP
(
Interior Gateway Routing Protocol
)
■
EIGRP
(
Enhanced Interior Gateway Routing Protocol
)
■
OSPF
(
Open Shortest Path First
)
■
IS-IS
(
Intermediate System-to-Intermediate System
)
■
BGP
(
Border Gateway Protocol
)
■
Routing Table Principles Exercise
In your own words, describe the three routing table principles according to Alex Zinin in his topic
Cisco IP Routing
.
1
Instructor note:
The student should restate the principles. The following answers are examples.
Principle #1:
Each router makes a routing decision solely based on information in its own routing
table.
Principle #2:
Just because the local router has a route in its table does not mean that other routers
have the same route.
Principle #3:
Even though a router can route to the destination does not mean that the same router can
route a response back to the originating source.
Refer to Figure 1-6. R2 received a packet from R1 destined for PC2. R2 did not have a route for the
network that PC2 belongs to, so R2 discarded the packet. Which routing principle does this illustrate?
Routing Principle #2
Figure 1-6
Routing Principles: Example 1
PC1
PC2
R1
R2
R3
Packet
Discarded
Refer to Figure 1-7. R3 received a packet from R2 destined for PC2. R3 sent the packet on to R2. But
when R2 sent a response to PC1, R3 discarded the packet. Which routing principle does this illus-
trate?
Routing Principle #3
Figure 1-7
Routing Principles: Example 2
PC1
PC2
R1
R2
R3
Packet
Discarded
