If you have access to your site and you’ve not been blocked, you can enter your IP or IPv6 address(es) by going to Jetpack → Settings → Protect → Configure.
If you are blocked from entering your site, you can enter the IP or IPv6 address(es) via WordPress.com by visiting My Sites → Settings → Security → Whitelist.
You can also whitelist one IP address by setting it as theJETPACK_IP_ADDRESS_OK constant in your wp-config.php
define('JETPACK_IP_ADDRESS_OK', 'X.X.X.X');
You can find your IP by visiting any of the following sites: http://www.whatsmyip.org
Be sure to replace X.X.X.X with your own IP address.