> For the complete documentation index, see [llms.txt](https://karansingh.gitbook.io/aws-saa-c02/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://karansingh.gitbook.io/aws-saa-c02/ec2/ip-addresses.md).

# IP Addresses

* **When you start and stop an instance with a public IPv4 address, its public IPv4 address changes**.<br>
  * However, this **can be solved with Elastic IP addresses.**

## Elastic IP addresses

* It is is a **static IPv4 address designed for dynamic cloud computing**.<br>
* You can **mask the failure of an instance or software by rapidly remapping the address to another instance in your account.**<br>
* An Elastic IP address is allocated to your AWS account, and is yours until you release it.<br>
* A **public IPv4 address** (reachable from the internet).