26. Which command should a network administrator issue to disable default summarization in an EIGRP network?
• Router(config-router)# null 0 route
• Router(config-if)# no ip summary-address
• Router(config-router)# no ip summary-address
• Router(config-if)# no auto-summary
• Router(config-router)# no auto-summary
27. 
Refer to the exhibit. Users on the 172.30.20.0/24 network are unable to access any of the servers located on the 192.168.0.0/23 network. Given the network topology and OSPF configuration, what two problems exist in this network? (Choose two.)
• There is a routing loop occurring between all three routers.
• There is a network statement missing.
• Network 172.30.20.0 has an incorrect wildcard mask.
• The OSPF Area configuration is incorrect.
• /23 is an invalid subnet mask for the 192.168.0.0 network.
28. 
Refer to the exhibit. Which IP addressing scheme would be correct for the network?
• H1-172.18.0.10/16
H2-172.18.0.11/16
H3-172.18.0.12/16
• H1-172.18.0.10/16
H2-172.19.0.10/16
H3-172.18.0.11/16
• H1-172.18.0.10/16
H2-172.18.0.11/16
H3-172.19.0.11/16
• H1-172.18.0.10/16
H2-172.19.0.11/16
H3-172.19.0.11/16
29. 
Refer to the exhibit. An administrator is adding a new router to the network. The IP address 192.168.13.6/30 has been assigned to the connecting serial interface on R2. What IP address must the administrator assign to the serial interface of the new router?
• 192.168.13.4/30
• 192.168.13.5/30
• 192.168.13.7/30
• 192.168.13.58/30
• 192.168.13.61/27
• 192.168.13.63/27
30. After comparing a previous baseline to current network statistics, the network engineer has discovered a significant increase in unwarranted traffic to the extranet. Which two steps simplify administration and control the unwanted traffic? (Choose two.)
• define an ACL at the distribution layer to isolate packets
• add an ACL at the router in the enterprise edge to block the traffic
• deploy a Layer 3 switch to contain broadcasts
• connect remote locations directly to the intranet
• configure all hosts with the same default gateway to eliminate unnecessary broadcasts
• deploy one core ISP router to reduce the delay in path determination
