Masoud Binaei

This plugin allow WordPress to detect Real visitors IP Address when WordPress is behind of Reverse Proxy, Load Balancer or CDN. 
It will start working as soon as you activate it.
It is also compatible:
<ul>
<li>Cloudflare.com</li>
<li>geniusguard.com</li>
<li>central-hosting.com</li>
<li>incapsula.com</li>
<li>sucuri.net</li>
<li>barracuda.com</li>
<li>f5.com And Other…</li>
</ul>

Real IP Detector

Very good

This plugin allow WordPress to detect Real visitors IP Address.

Minor

Simple plugin to secure your WordPress admin interface thanks to IP whitelisting. Only IP addressess on the whitelist (external whitelist supported) have an access into admin interface.
Another possibility how to access WordPress administration is thanks to secret admin link (you still need to insert correct user login and password).
Your IP address is whitelisted and secret admin link generated every time at plugin activation!

Secure Admin IP

Simply restrict login to your WordPress for the specific IP addresses or users with secret link.

Real IP Detector vs Secure Admin IP