Ccna Studies
Question 1
Your boss is learning a CCNA training course, refer to the exhibit. The access list has been configured on the S0/0 interface of router RTB in the outbound direction. Which two packets, if routed to the interface, will be denied? (Choose two)
access-list 101 deny tcp 192.168.15.32 0.0.0.15 any eq telnet access-list 101 permit ip any any
A. source ip address: 192.168.15.5; destination port: 21 not telnet port
B. source ip address: 192.168.15.37 destination port: 21 not telnet port
C. source ip address: 192.168.15.41 destination port: 21 not telnet port
D. source ip address: 192.168.15.36 destination port: 23 satisfies telnet port, in correct range of addresses to satisfy access-list
E. source ip address: 192.168.15.46; destination port: 23 satisfies telnet port, in correct range of addresses to satisfy access-list
F. source ip address: 192.168.15.49 destination port: 23 satisfies telnet port, not in range of addresses Answer: D E
Explanation
First we notice that telnet uses port 23 so only D, E & F can satisfy this requirement.
The purpose of this access-list is to deny traffic from network 192.168.15.32 255.255.255.240 (to find out the subnet mask just convert all bit “0″ to “1″ and all bit “1″ to “0″ of the wildcard mask) to telnet to any device. So we need to figure out the range of this network to learn which ip address will be denied. Subnet mask is /28, so 4 bits borrowed.
128 64 32 16 8 4 2 1
0
16
32 33-46 47 is broadcast
48
Increment: 16
Network address: 192.168.15.32
Broadcast address: 192.168.15.47
-> Only 192.168.15.36 (Answer D) & 192.168.15.46 (Answer E) belong to this range so they are the correct answer.
Question 2
Refer to the graphic. It has been decided that PC1 should be denied access to Server. Which of the following commands are required to prevent only PC1 from accessing Server1 while allowing all other traffic to flow normally? (Choose two)
A – Router(config)# interface fa0/0
Your boss is learning a CCNA training course, refer to the exhibit. The access list has been configured on the S0/0 interface of router RTB in the outbound direction. Which two packets, if routed to the interface, will be denied? (Choose two)
access-list 101 deny tcp 192.168.15.32 0.0.0.15 any eq telnet access-list 101 permit ip any any
A. source ip address: 192.168.15.5; destination port: 21 not telnet port
B. source ip address: 192.168.15.37 destination port: 21 not telnet port
C. source ip address: 192.168.15.41 destination port: 21 not telnet port
D. source ip address: 192.168.15.36 destination port: 23 satisfies telnet port, in correct range of addresses to satisfy access-list
E. source ip address: 192.168.15.46; destination port: 23 satisfies telnet port, in correct range of addresses to satisfy access-list
F. source ip address: 192.168.15.49 destination port: 23 satisfies telnet port, not in range of addresses Answer: D E
Explanation
First we notice that telnet uses port 23 so only D, E & F can satisfy this requirement.
The purpose of this access-list is to deny traffic from network 192.168.15.32 255.255.255.240 (to find out the subnet mask just convert all bit “0″ to “1″ and all bit “1″ to “0″ of the wildcard mask) to telnet to any device. So we need to figure out the range of this network to learn which ip address will be denied. Subnet mask is /28, so 4 bits borrowed.
128 64 32 16 8 4 2 1
0
16
32 33-46 47 is broadcast
48
Increment: 16
Network address: 192.168.15.32
Broadcast address: 192.168.15.47
-> Only 192.168.15.36 (Answer D) & 192.168.15.46 (Answer E) belong to this range so they are the correct answer.
Question 2
Refer to the graphic. It has been decided that PC1 should be denied access to Server. Which of the following commands are required to prevent only PC1 from accessing Server1 while allowing all other traffic to flow normally? (Choose two)
A – Router(config)# interface fa0/0