Question

A packet with the destination IP address 145.36.109.70 arrives at a router whose routing table is shown. Which interface will the packet be forwarded to? 

 

• A. E1
• B. E2
• C. E3
• D. E5

Hint:

When checking a destination IP address against a routing table, compare it with each subnet using the subnet mask and find the longest matching prefix.

Answer 1

The Correct Option is A

We are given the destination IP address \( 145.36.109.70 \), and we need to find which interface the packet will be forwarded to based on the routing table.

1. Convert the IP address to binary form:
The given IP address is \( 145.36.109.70 \), and in binary form it is: \[ 145 = 10010001, \quad 36 = 00100100, \quad 109 = 01101101, \quad 70 = 01000110 \] So, the binary form of \( 145.36.109.70 \) is: \[ 10010001.00100100.01101101.01000110 \]
2. Check against the routing table:
For Subnet 145.36.0.0/16:
The subnet address 145.36.0.0 with the subnet mask /16 covers addresses from 145.36.0.0 to 145.36.255.255.
The given IP address 145.36.109.70 falls within this range. Therefore, it matches this subnet.

3. Conclusion:
Since the IP address \( 145.36.109.70 \) falls under the subnet 145.36.0.0/16, it will be forwarded to Interface E1.

Thus, the correct answer is \( \boxed{A} \).