## SEO: Subfolder vs Subdomain
**Question: Can I use ReadMe on subfolder (website.com/docs) rather than a subdomain (docs.website.com)?**
We only offer a subdomain (docs.website.com) option in order to keep ReadMe simple and easy to use.
There are numerous technical challenges that prevent a third party (like ReadMe) from creating a subfolder on your domain while maintaining the level of performance we are committed to maintaining.
## Caching
**Question: Sometimes pages aren't updated immediately, is there some form of caching?**
Pages are currently cached for 15 minutes, for only logged out users. If you are logged in, then you will always receive the most recent content.
## IP range
**Question: What is ReadMe's IP range? I would like to whitelist it.**
We have a [dynamic IP](🔗), so there isn't a range we can provide. It is often not desirable to open up your firewall to the whole of the AWS region for security reasons. If you wanted to do this regardless you can find the published IP ranges from AWS [here](🔗).