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The Network Layer - IP addresses

7 important questions on The Network Layer - IP addresses

How many bits does an IPv4 address consist of?

An IPv2 address is a 32-bit long value

The IPv4 addresses are divided in 5 classes. How do we divide the classes that allows us to know which IP class they belong to?

We divide the IPv4 address classes by dividing the first octet from 0 to 255 into five groups.

With which number does a class A IPv4 address start?

A class A IP4v address starts with 0

With which number does a class E (the last class) IPv4 addres start?

A class E IP4v address starts with 255

How do we determine the numbers each IP class starts with?

To decide what the other IP classes start with, we need the binary table. We used this table to convert from binary to decimal or vice versa.

The binary table is as follows:
128 64 32 16 8 4 2 1

Class A starts with 0
Class B starts with 128
Class C starts with 192, because we add 128 + 64
Class D starts with 224, which is the sum of 128 + 64 + 32
Class E starts with 240, which is the sum of 128 + 64 + 32 + 16

What is the IP range of each IP class in decimal

Class A: 0 - 127
Class B: 128 - 191
Class C: 191 - 223
Class D: 224 - 239
Class E: 240 - 255

In binary, what does the first octet of an IP address look like per class?

Class A: starts with 0, this number is fixed. The rest is any combination of 0s and 1s. So it looks like: 0XXXXXXX

Class B: 10XXXXX

Class C: 110XXXXX
Class D: 1110XXXX
Class E: 1111XXXX

The question on the page originate from the summary of the following study material:

Google IT Support Professional Certificate

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