Cisco CCNA mock exam questions sample test – Question 381

.Refer to the network diagram in the exhibit. Host A is configured with an incorrect default gateway. All other computers and the Router are known to be configured correctly (Click the
Exhibit(s) button.)
Which of the following statements is TRUE?

A. Host C on Network A cannot communicate with Host A on Network A.
B. Host A on Network A can communicate with all other hosts on Network A.
C. Host A on Network A can communicate with Router R.
D. Host C on Network A cannot communicate with Router R.
E. Host D on Network B cannot communicate with Host B on Network A.

Correct Answer: BC

Explanation:
Host A on Network A can communicate with all other hosts on Network A and with Router R. To communicate with local hosts and the interface of Router R (which are all in the same
subnet) only a correct IP address is reqired. If the default gateway of Host A is incorrect, then it will not be able to communicate with any host on the other side of the router, which
includes Network B in the diagram. Packets from hosts on Network B will reach Host A on Network A without any problem, because they possess the correct address of the default
gateway or router, but Host A will send the packet to a dead end because Host A has an incorrect default gateway. On the other hand, Host A does not require a default gateway to
communicate with other hosts on same network.
Host C on Network A WILL be able to communicate with Host A on Network A , even though Host A has an incorrect default gateway because Host A and C are in the same subnet,
which requires no use of the of the gateway or router..
Host C on Network A WILL be able to communicate with Router R because Host C has the correct default gateway address which is the address of Router R.
Host D on Network B WILL be able to communicate with Host B on Network A because both hosts have a correct default gateway address.
Objective:
Routing Fundamentals
Sub-Objective:
Troubleshoot basic Layer 3 end-to-end connectivity issues
References:
Cisco > Internetworking Technology Handbook > Internetworking Basics > Routing Basics
http://www.microsoft.com/technet/community/columns/cableguy/cg HYPERLINK “http://www.microsoft.com/technet/community/columns/cableguy/cg0903.mspx”0903 HYPERLINK “http://www.microsoft.com/technet/community/columns/cableguy/cg0903.mspx”.mspx
http://kb.iu.edu/data/ajfx.html