PrepAway - Latest Free Exam Questions & Answers

Which network ID should you use?

DRAG DROP
You are configuring a test network. The test network contains a subnet named LAN1. LAN1 uses the network
ID of 10.10.1.0/27.
You plan to add a new subnet named LAN2 to the testnetwork.
LAN1 and LAN2 will be connected by a router.
You need to identify a valid network ID for LAN2 that meets the following requirements:
Ensures that hosts on LAN2 can communicate with hosts on LAN1.
Supports at least 100 IPv4 hosts.
Uses only private IP addresses.
Which network ID should you use?
To answer, drag the appropriate network ID and subnet mask to the correct location in the answer area.

PrepAway - Latest Free Exam Questions & Answers

Answer:

Explanation:

10 Comments on “Which network ID should you use?

  1. jo says:

    Confirmed.

    Borrowing one bit from the last octet will give us at least 100 usable IPs; with prefix /25 one can get 126 usable IPs because the number of hosts is calculated by 2^[to the power of](32-25) -2 which is 2^7 – 2= 128-2=126;
    Since we borrow one bit, we would only have 2 subnets: 2^1=2. The block size is 128 (2^32-25)
    Therefore network 10.10.1.0/25 can only get 2 subnets in increments of 128:10.10.1.0 and 10.10.1.128. With usable IP ranges of 10.10.1.1 to 10.10.1.126 and 10.10.1.129 to 10.10.1.254
    The new subnet required in order to get at least 100 hosts is 10.10.1.128/25, /25 being 255.255.255.128
    In case we only needed 50 IPv4 hosts, we would reserve 6 bits in the last octet for the host id, 2^6=64, enough to get your 50 IPs; we would get 2^(32-26)-2=62 hosts for each of the 4 subnets (2^2, 2 being the number of bits borrowed). The block size would be 64.
    10.10.1.0
    10.10.1.64
    10.10.1.128
    10.10.1.192

    Then 256-64 (the block size)=192 (the subnet mask): 255.255.255.192




    1



    0

Leave a Reply