In reply to a post by BatBoy:

Try lowering your RWIN or increasing interleaving

Have played with lots of values of Rwin and even tried on Win 7 - no different. Is it possible to increase interleaving from user side?

Even if you set rwin approaching the value for MTU?

I think interleaving depth or even INP is an ISP function, so good luck with the reseller...

Are you on fastpath though?

In reply to a post by BatBoy:

Even if you set rwin approaching the value for MTU?

I think interleaving depth or even INP is an ISP function, so good luck with the reseller...

Are you on fastpath though?

I use TCP Optimzer to set Rwin and have tried several values both slow and fast line speed all a function of 1500 MTU. Billion suggested turning off Jumbo Frames but this made no difference.

Interleaving is on but not sure what depth need to look deeper.

I was thinking you are getting packet loss due to noise and a quick test is to set the rwin to a low multiple of mtu, like 1 or 2 times, just to see if it eliminates the pauses.

But the router is suspect as replacing it fixes the problem...

In reply to a post by mixt:

This is a truly an illusive problem!

Ok, another question. When you are downloading, are you maxing out your line speed? (if so, how fast?).

Can you rate-limit the download? (possibly better to download from a site that rate limits their side) to see if you still get pauses during a download running at a slower speed?

It sounds like a buffering problem, or like the Billion is tripping over itself (or something). Still not really sure to be honest.

Have found a 2 mbps limited download from the states and a 45mb file pause 3 times. That help?

In reply to a post by BatBoy:

I was thinking you are getting packet loss due to noise and a quick test is to set the rwin to a low multiple of mtu, like 1 or 2 times, just to see if it eliminates the pauses.

But the router is suspect as replacing it fixes the problem...

I will try that with Rwin. But Billion Lab cant recreate this and have sent screen shots of their efforts and other users on this forum have confirmed it doesn't happen to them.

It rules out the Billion being overloaded anyway.

Another question. How many platforms do you have available to you? You're doing the download on Windows, right? Can you test the same download on Linux / Mac ? Maybe even a mobile phone? See if pauses still happen on those?

In reply to a post by mixt:

It rules out the Billion being overloaded anyway.

Another question. How many platforms do you have available to you? You're doing the download on Windows, right? Can you test the same download on Linux / Mac ? Maybe even a mobile phone? See if pauses still happen on those?

Unfortunately only have Windows (XP) platforms available and Win 7 as a virtual machine. Can try some other virtual machines but they are all Windows. No Mac or Linux to test.

Tried some low Rwin values, 3000 and 12000 on my system. 3000 no pauses after 10 minutes but didnt download all 360 mb at 500 kbps. Then tried 12000 to give a speed of around 2.63 mbps and got a pause after about 5 mins. So it seems that the lower the Rwin value the less ofted the pauses at slower speeds. What this proves I have no idea.

This is a replacement router as well, right? (as in, you got the first Billion router, returned it, and got another one, and this one is still doing it?).

I'm out of ideas but I can only guess there is some conflict between the way the TCP stack on your system and the router's NAT is interacting, because as you say, this problem doesn't show if you go back to your SpeedTouch.

On what system are you doing the downloads on? The host system? Or on a guest system? What OS are the host and guest running? (since you mention you are running some virtual machines). If on the guest system, what OS and what virtualisation software are you using? How are you placing the guest onto your network? (is it via NAT, so we effectively have a double NAT scenario happening on guests) or are you bridging the guest interfaces to the host?

I'm actually up for helping further (if you have the time) - for example, I can setup a large file on my VPS server and let you download it, and run a packet capture server side just to see if there's anything more sinister happening. I don't think much more can be done unless this is done (or you want to send me some of your WIreshark pcap files). Happy to take a look though as it certainly is an intriguing issue. PM if you're interested.

Yes this is the second billion router. Host system is XP have various guest systems which include Win 7. Will PM you with more detail and a wireshark file.