IPv4 Addressing Overview

What is the primary purpose of private IPv4 addresses?

Which class of IPv4 addresses has the most host bits available?

How many network bits are allocated for Class B IPv4 addresses?

Which organization is responsible for assigning IP address space to ISPs and end users?

What happens to private IP addresses on the Internet?

Which of the following is NOT a characteristic of Class C IPv4 addresses?

What is the main requirement for an end user to qualify for receiving a block of IP addresses from ARIN?

Which octet in the binary representation of the IP address 10.10.20.1 indicates it as a Class A address?

What distinguishes private addresses from public addresses in terms of routing?

What do the numbers in a Class B network address indicate in terms of bits?

IPv4 Addressing

IPv4 addresses are 32 bits long, divided into four octets (8-bit chunks)
Each octet is represented in decimal form (0-255)
Example: 10.10.20.1 (decimal) = 00001010.00001010.00010100.00000001 (binary)

IPv4 Address Classes

Addresses are categorized into classes (A, B, C, D, E) based on the initial bits.
Class A: 0.0.0.0 to 126.255.255.255 (Network = 8 bits, Host = 24 bits)
Class B: 128.0.0.0 to 191.255.255.255 (Network = 16 bits, Host = 16 bits)
Class C: 192.0.0.0 to 223.255.255.255 (Network = 24 bits, Host = 8 bits)
Class D: 224.0.0.0 to 239.255.255.255 (Used for multicast)
Class E: 240.0.0.0 to 254.255.255.255 (Reserved)

Network and Host Bits by Class

The octets of an IP address are divided into network (prefix) and host portions. | Class | Network Bits | Host Bits | |---|---|---| | A | 8 | 24 | | B | 16 | 16 | | C | 24 | 8 |
This determines how many addresses are available for each class.

Number of Host Addresses by Class

Class	Number of Host Bits	Number of Hosts
A	24	16,777,214
B	16	65,534
C	8	254

Private IP Addresses

Certain IP address ranges are reserved for internal networks (intranets).
These private addresses aren't routed on the public internet. | Class | Address Range | |---|---| | A | 10.0.0.0 to 10.255.255.255 | | B | 172.16.0.0 to 172.31.255.255 | | C | 192.168.0.0 to 192.168.255.255 |
Non-routable IPs: Private addresses are blocked from the public internet by ISPs.

ARIN

ARIN (American Registry for Internet Numbers) manages IP address allocation.
They assign blocks of addresses to ISPs and, in some cases, end-users.
Requirements for receiving IP address blocks from ARIN generally involve meeting certain criteria of size, user base and purpose of the request.

This quiz explores the fundamentals of IPv4 addressing, including the structure of IPv4 addresses and their classification into various classes. Each class has distinct characteristics regarding network and host bits, which impacts the number of addresses available. Test your understanding of these concepts and how they apply to networking.