MCQ IN COMPUTER SCIENCE & ENGINEERING

Detailed explanation-1: -nnn. Let’s call each group an octet as it is 8 bits. The reason that the highest octet value is 255 is that IP addresses are given in bits, which are the power of 2. The maximum number you can write with bit notation is with 8 1’s or 11111111=255.

Detailed explanation-2: -Each number in the set can range from 0 to 255. So, the full IP addressing range goes from 0.0. 0.0 to 255.255.

Detailed explanation-3: -Remember, again, that binary host addresses with all ones or all zeros are invalid, so you can’t use addresses with the last octet of 0, 63, 64, 127, 128, 191, 192, or 255. You can see how it works by looking at two host addresses, 192.168.123.71 and 192.168.123.133.

Detailed explanation-4: -A subnet mask is a 32-bit number created by setting host bits to all 0s and setting network bits to all 1s. In this way, the subnet mask separates the IP address into the network and host addresses. The “255” address is always assigned to a broadcast address, and the “0” address is always assigned to a network address.

Detailed explanation-5: -Although expressed in the form of an IP address number, network devices use 255.255. 255.0 as a mask and not as a working IP address. Attempting to use this number (or any IP number that starts with 255) as a device address causes the IP network connection to fail due to the definition of number ranges on IP networks.