04. Addressing
Addressing
IPv4 Addressing
Addressing Space
Here's a visualization of the entire IPv4 address space. Each square represents one possible value of the first octet of an address. For instance, the square on the top right, labeled 15, represents all the IPv4 addresses that start with 15 as their first octet (e.g. 15.72.9.277).
Visualization of the IPv4 address space. Each square represents the first octet of an IPv4 network address.
- The pink squares (
0,10, and127) are blocks that are entirely reserved. - The blue squares are blocks that are partially reserved. For instance, not all of the
192block is reserved, but some of it is. - The entire green row (starting at
224) is set aside for IP multicast. - And the entire orange bottom row (starting at
240) was originally set aside for "future use" but was effectively lost due to being blocked as invalid.
Public IP Addresses?
SOLUTION:
- 8.8.8.8
As you can see, there aren't enough IP addresses to go around - but we'll get into how we manage that a little bit later!