Internet

Once you start to integrate services with Telcos, ISPs or other major Network players who are not “Cloud Aware”, you will need to go the VPN way using IPSec. Their setups have used all the available IP’s defined by RFC 1918 (or just don’t want to use them). They will want to use Public IP’s behind your VPN. The problem is that your EC2 instances are running behind a 1:1 NAT with only a private IP’s attached to them. To add to the complexity, your instances are part of an auto-scaling group, with IP’s all over 10.0.0.0/8. Luckily the way to solve this problem is actually quite easy, we just need to add some iptables rules and a proxy.

Everybody is aware that WordPress is a heavy truck to display some “mostly” static content. Each Plugin or Widget that is added ads some stylesheet calls, javascript calls and database requests. This all together slows up the loading time of your blog. And it gets even worse when the site become popular and has to deal with thousands of requests. Why request for each visitor something from the database when the content only changes once in a while? Why go through all the PHP logic when the final rendered HTML is always the same?

Everyone is aware of tools like speedtest.net to get a sens of the Internet connectivity speed to certain regions. While it works on mostly every device it allows you to test speed to only one server at a time. And is primarily meant to test the speed of your ISP. I wanted to test connectivity to several part of the world in an one click way, usable on multiple devices. The answer didn’t struck me at once, but it all can be done with some Javascript and mainly with the xhr object.