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I am on a windows machine on a network which connects thousands of users including myself onto internet1 which when congested gets very slow. The linux machine however although connected to the same network uses a separate internet2 (very fast due to low usage).

I used putty to create an SSH tunnel to the linux machine in order to gain access to the faster internet, however the speed does not seem to change whatsoever.

The weird thing is I also have virtual box installed on my machine with a copy of linux installed on that which i run in a window. With that I opened an SSH tunnel and ran firefox through that. These are the results i got using pingtest . net

During peak hours.
internet1(using putty and socks5 in firefox options): 1200ms
internet2(using virtual box w/ ssh -x tunneled firefox): 35ms

here is a little visual representation of what I think the network looks like.

   |                      |
   |                      |
   |                      |
   |                      |

final note*
-I feel that maybe putty might be using my internet1 to access the linux server then go through internet2. I tried setting network.proxy.socks_remote_dns value to true in the config settings of firefox (as default is false) but it had no effect whatsoever. So I set it back to false.

Does anyone have any suggestions on how to resolve this? (Thank you in advance)

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up vote 1 down vote accepted

It looks like you are using the public internet domain name or the internet IP address associated with your linux server in order to do the port forwarding. The path essentially looks like this:

windows -> internet1 -> internet2 -> linux -> internet2

What you want to do is use the internal IP address or internal name that is associated with the linux system. If you do an ipconfig in the windows terminal, you will see that your ip address starts with something like 192.168.x.x or 10.x.x.x. When you are ssh'd into your linux server, do an ifconfig to get its ip address internal to your network and use it instead. This would give you a connection that looks more like this:

windows -> linux -> internet2

By the way, if you use ssh -X from your virtualbox linux and then run firefox from the command line, you essentially see what you would see if you were using firefox physically at the linux server. It does not produce an accurate comparison for your purposes. It is kinda like vnc or remote desktop.

To produce a more accurate comparison in virtualbox, use ssh -D localhost:4000 username@linuxServer and then use the firefox proxy settings just like you did in windows.

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How do you arive at this conclusion >It looks like you are using the public internet domain name or the internet IP address associated with your linux server in order to do the port forwarding. The path essentially looks like this: windows -> internet1 -> internet2 -> linux -> internet2 – Bond Jan 29 '11 at 19:10
@Bond I arrived at that conclusion based on your two pingtest results. Your ssh -X test shows that the linux server probably does have a faster internet connection. Your proxy test with putty shows that something between you and the server is slowing down the connection. The latency between the computers on my internal network is less than 1 ms. The latency between the computers on your network is probably similar. Your latency using the linux server as a proxy should be in the 30's or 40's, not 1200. That is why I think you are connecting through your slow internet to connect to the server. – James T Jan 29 '11 at 20:20
@Bond The diagram that I showed with "windows -> internet1 ..." is basically just saying that it looks like you are connecting to the internet in order to connect to the linux server, which you are then using to connect to the internet again. This is purely based on your ping tests. It could be that your internal connection to the linux server is very slow, but I find it more likely that you are connecting to the linux server through your slow internet. Try pinging your linux server from the windows system. – James T Jan 29 '11 at 20:26
@Bond also (from windows) run a tracert on the linux hostname or ip address that you are using. It will show you how many times it bounces around on the internet before you are connected to the linux server. – James T Jan 29 '11 at 20:29
@Bond and your right, it could be caused by other things that I may not have thought of... like if the server processing power is maxed out, or if there is high demand on the local network to communicate with the server. – James T Jan 29 '11 at 21:20

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