$( "iframe" ).load(function() {
   $("iframe").contents().find("b").html(function(_, html) {
      return html.replace(/(bd{1,3}.d{1,3}.d{1,3}.d{1,3}b)/, '<a href="http://$1/" target="_blank">$1</a>');
   });
});
       
<li>
    <ul>
        <li>
            <b>MyRouter1 - 192.168.1.1</b>
        </li>
        <li>
            <b>MyRouter2 - 192.168.1.2</b>
        </li>
    </ul>
</li>