Download speed drops thru open vpn router

Hi

I live outside of the UK and my download speed via the local ISP is 8Mb with a latency of 25-30 ms. If I use a VPN to stream video from the UK, the download speed drops to 5.5 - 6 Mb and latency to 90 - 105 ms which is fine.
My modem is a Thomson TG585 v7 with 4 outputs. I have connected one of these outputs to a Linksys WRT54GL router which is set up with DD WRT and Open VPN.
This works fine but with one small problem which I hope you might help me to make sense of. (By the way my VPN supplier tried to help but was unable to even though we set up remote assistance).
The problem is that although latency remains at 90-105 ms the download speed drops to 2.4 - 2.6 Mb. So I increased my local ISP's download speed to 12 Mb thinking that it would work through and up the Open VPN speed, but no. it remains stubbornly at 2.4 - 2.6 Mb. (normal VPN did increase to 8 Mb.)
I can understand that the latency will remain the same but I am wondering if the Linksys router has a top limit? Perhaps that is the wrong term but as a silver surfer any answers please put it as simply as you can.

Thanks
hamishman

I am going to assume that you are legally allowed to use the streams and are using VPN for some other reason...

Throughput drops may be down to settings for the MTU within the routers. It's possible that the Linksys MTU is set wrongly and is causing the throughput to be reduced because of this.

Latency to where?

Unless you compare the latency figures to EXACTLY the same point with and without a VPN it is like comparing apples and runner beans.

And why do you need a VPN to stream video? Most services, unless it is on your or your employer's server, do not require a VPN.

In reply to a post by MHC:

And why do you need a VPN to stream video?

National boundary restrictions?

In reply to a post by XRaySpeX:

In reply to a post by MHC:

And why do you need a VPN to stream video?

National boundary restrictions?

Which breaks copyright law.

Interesting question about latency. If pinging a site in the OPs local country then latency would expect to increase significantly (as over the VPN it would have to travel to the UK and then back again). If pinging a UK address though the difference should not be so high as the hop from the VPN termination to the UK site will be relatively shortened.

In reply to a post by MHC:

Which breaks copyright law.

Hence my original statement that I am assuming they have some other reason to do this as not too keen on helping people illegally watch streams. British TV is controlled and using VPNs to access breaks the copyright - otherwise why need a VPN? But the OP hasn't answered that yet.

Exactly. And if you heard the hoops that parts of my industry have to go through to protect copyright, you might not believe it initially.

Be aware with VPN the throughput depends on the CPU of each device doing the encryption and decryption.

So for example if you were previously using your computer as the OpenVPN client (or server) then switch to using an old router as the OpenVPN client (or server) you may expect the throughput to drop in comparison.

Some VPN routers are able to offload the maths to another chip (hardware acceleration) or have a family of CPU with a faster implementation (typically for AES).

Note that you don't actually need encryption if it just to reach another endpoint (for streaming you say in your case),
so something like L2TP without IPSec is also fine if you only need to tunnel but not encrypt.

Back to your setup, I don't know if OpenVPN has a similar "tunnel only" option, if not, see if you have different options from AES, 3DES. DES, Blowfish as some may be faster on given hardware.

Disclaimer - I am responding only to the technical aspects of the question. Others have already asked about another aspect.

Edited by prlzx (Fri 12-Apr-13 23:23:28)

Thank you for all your replies. I am afraid my technical ability slowed considerably after I had mastered beam powered tetrodes. I was just curious to what the problem was.