A network administrator has decided to use VLSM to subnet the 10.11.0.0/20 network to provide addresses for two new departments and the point-to-point link that separates the two departments. The first department has 796 users and the second department has 31 users. The WAN link requires only two addresses. Which of the following subnets will provide the required contiguous space and waste the fewest addresses? (Choose three.)

IT Questions Bank › Category: CCNA 1 v6 › A network administrator has decided to use VLSM to subnet the 10.11.0.0/20 network to provide addresses for two new departments and the point-to-point link that separates the two departments. The first department has 796 users and the second department has 31 users. The WAN link requires only two addresses. Which of the following subnets will provide the required contiguous space and waste the fewest addresses? (Choose three.)

10.11.0.0/21
10.11.0.0/22
10.11.253.0/25
10.11.253.0/26
10.11.253.128/29
10.11.253.64/30

Explanation: To produce a subnet that could accommodate 796 users would require 10 bits (1024 hosts). To accommodate 31 users would require 6 bits (64 hosts). The WAN links require 2 bits (four hosts). Starting with the largest subnet would require borrowing 2 bits, leaving the 10 bits for hosts. This creates a 10.11.0.0/22 network, which includes the range 10.11.0.0/22 – 10.11.251.255/22. The second network requires 6 bits, can start at 10.11.253.0/26, and would run to 10.11.253.63/24. The third network would start at the next available address (10.11.253.64/30) and run until 10.11.253.67/30.

Exam with this question: CCNA 1 ITNv6 Chapter 8: Check Your Understanding