IP-Exclusive Directory Access

A directory that can be accessed only with your IP address is good security. The directory will let in only your IP address. Nobody else can get in, not even bots.

Every internet connection has its own IP address, which makes its connection unique among all internet connections in the world. When browsers and bots asks a server for information, they provide the server with their internet connection IP address. Their IP address is how a server knows which browser to respond to. (If a bot tries to spoof an IP address, they can not get any response at all from the server.)

Their IP address is not the same as your IP address. Only you have your IP address because only you have your internet connection. Thus, only you can access that directory.

Note that more than one browser can have the same IP address. But they must be connected to the internet with the same connection as you. For example, your family may have the same IP address as you do. But your neighbor does not, unless they hacked your Wi‐Fi.

To set it up, select or create a directory for the protection. Then, put these lines into the .htaccess file for that directory.

SetEnvIf REMOTE_ADDR 127.0.0.1 allow_this=1
Order Deny,Allow
Deny from all
Allow from env=allow_this

Replace 127.0.0.1 with your IP address and you are good to go. (If you do not know your IP address, the Willmaster IP address page can be used.)

For testing, try to access the directory with an IP address other than the one you have specified as being allowed. If you have no other way immediately available, the Tor browser can be used; it operates with a different IP address.

It is possible to enable more than one IP address. Perhaps you use more than one internet connection during the course of your work and home activities. Or perhaps you frequently visit relatives who have a different ISP.

To allow additional IP addresses, repeat the SetEnvIf... line. Example, for allowing three IP addresses:

SetEnvIf REMOTE_ADDR 127.0.0.1 allow_this=1
SetEnvIf REMOTE_ADDR 127.0.0.11 allow_this=1
SetEnvIf REMOTE_ADDR 127.0.0.111 allow_this=1
Order Deny,Allow
Deny from all
Allow from env=allow_this

The IP-address method is a quick way to protect a directory without having to implement a cookie and/or log‐in system.

(This content first appeared in Possibilities newsletter.)

Will Bontrager