Work around ISP QoS limitations
Friday, May 29th, 2009ISPs which enforce QoS limitations suddenly, without alerting the customer, are abusing their force. QoS limitation is not a bad thing, from the ISP’s point of view, but changing the customer deal without notifying him seems to me to be unfair.
This is a recipe for a QoS workaround.
Ingredients:
- One fast Internet connection which is not used to its full capacity
- Defined target service provider. I use Giganews as an NNTP, which is the fastest method of obtaining content today. You should have the service list of IPs. Luckily, Giganews use only two IP addresses
- One “evil” ISP which enforces QoS for external targets
- One server in the ISP’s hosting farm, which has no speed or transfer limitations, and is probably not bound by the ISP’s QoS
- For a better looking dish – some graphing solution, such as Cacti or MRTG
Directions:
- Setup OpenVPN Server on the hosted server
- Setup OpenVPN Client on your NNTP/Other service client (your desktop, your Linux router, etc) – This can also be a Windows machine, but configuration varies a bit.
- Define, in your OpenVPN client.conf line(s) which look like this:
route <SERVICE_IP>
route <SERVICE_IP2>
- If this is a router machine, activate NAT on it. Of course – remember to set this rule to work after reboot too!
iptables -t nat -A POSTROUTING -o tun+ -j MASQUERADE
- For your good feeling, try to pickup data from before and after, and compare.
- Start the OpenVPN Service on the server, on the client, and restart your NNTP/Other service downloads.
- Serve with a smile 🙂
The result dish is both tasty and good looking! see below:
A word of warning – OpenVPN is a VPN tool. As such, it uses encryption and varios methods which are very secure. This means that for high througput, such as mine (about 10Mb/s) you will see the impact on the router/workstation’s CPU. Under virtualization, I get about 2% additional system CPU utilization from a 2x3GHz Xeon CPU. For older router devices this could result in an overworked router. I am so glad I got rid of my old P2 350MHz router in favor of the virtualized one.