Question: I build a dashboard using PHP & MySql, where my company employees can log in, log out, request leaves, add work reports & maintain their attendance. everything was working fine, but my manager wants that dashboard to open only in our office network.
Since it's a simple task, I added the below code to the login page.

```
<?php
$ip = $_SERVER['REMOTE_ADDR'];  

if($ip == "xxx.xxx.xxx.xxx")
{
}
else
{
  header("Location: error.php");
}
?>

```

On the error.php page, I added an error message "You are not allowed to access this page".

The IP address I am using is from Google (IPV4). This was working fine but recently I realized the internet IP address changes often.
Now the condition is not working. So anyone can help me with which IP address I need to use in the conditions or what will be the solution for this.

Answer: 
There are two ways:

* You redirect based on IP address ranges to an error page. That is basically a webserver configuration task. It requires you to know which IP addresses traffic from your office uses. For changing IP addresses, you need to keep the two in sync.
* You move the whole server to your local office network. This is the preferred solution, because you have less infrastructure exposed to the (potentially hostile) internet.

Your approach is similar to the first one, only that you're trying to reimplement what your webserver already offers out of the box.
The issue has been resolved. If anyone looking for the answer,

The simplest solution I found on internet is allowing the entire subnet.

.htaccess code:

```
Order Deny,Allow
Deny from all
Allow from 111.111

```

Since the IPV4 is varying, I observed 1st 6 digits are static & only last 6 digits were varying.

So I removed PHP functions & using the above code in the htaccess I allowed the entire subnet (through 1st 6 digits)