Practice Test Geeks(ICND1) Interconnecting Cisco Networking Devices Part 1 Practice Test
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Subnetting Flashcards

7 cards from real ICND1 practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.

Read the first 7 Subnetting flashcards as text

  1. How many usable host addresses are available in a /27 subnet?

    Answer: 30

    A /27 subnet has 32 total addresses (2^5), minus 2 for network and broadcast, leaving 30 usable hosts.

  2. What is the broadcast address for the network 192.168.10.64/26?

    Answer: 192.168.10.127

    A /26 block is 64 addresses; starting at .64, the broadcast is .64 + 63 = .127.

  3. Which subnet mask corresponds to the CIDR notation /20?

    Answer: 255.255.240.0

    /20 means 20 bits are set, so the third octet has the top 4 bits set: 11110000 = 240, giving 255.255.240.0.

  4. A network administrator needs at least 50 subnets from 172.16.0.0/16. What is the minimum number of bits to borrow from the host portion?

    Answer: 6

    2^6 = 64 subnets, which satisfies the requirement of at least 50; 2^5 = 32 is insufficient.

  5. What is the network address for the host IP 10.4.77.130/25?

    Answer: 10.4.77.128

    A /25 mask is 255.255.255.128; ANDing 130 with 128 gives 128, so the network is 10.4.77.128.

  6. Which of the following IP addresses belongs to the subnet 192.168.5.128/26?

    Answer: 192.168.5.190

    The /26 subnet 192.168.5.128 covers .128–.191; only 192.168.5.190 falls in that range.

  7. How many subnets are created when you subnet 192.168.1.0/24 using a /28 mask?

    Answer: 16

    Borrowing 4 bits from a /24 (28 - 24 = 4) creates 2^4 = 16 subnets.