To break is down succinctly : -

I have a 80/20 mbps broadband connection.

When I do a speed test, I consistently only get 45 mbps downstream. This is tested over several days.

The problem occurs if I use it as the modem, or if I use the BT Openreach as the modem, and the Draytek just as a router.

The sync speed is fine (79812). And yes it is consistently fine, no dropouts. This has been confirmed by my ISP after days of monitoring.

If I swap the 2850 out for my cheapo TP-Link router, I get FULL speed (typically 75 mbps).... Again, consistently.

I've spent days on this, including contacting my ISP. They also concluded the problem was with the router.

I've tried re-flashing the latest firmware, using the .RST file to ensure everything is reset.. NO difference.

I'm on the verge of shelling out for a new router, because this just does not make sense. How can my cheap router outperform my Draytek speed-wise?

Would upgrading to the 2860 solve it? If it does that'll be my 3rd Draytek due to problems...

Thanks in advance,
Mark.

Well, it appears this is just Draytek's flaky software.

I've managed to get a fair bit more speed out of it, but I've had to jump through hoops to do it. See this post : -

http://forums.thinkbroadband.com/fibre/t/4579166-re-draytek-vigor-2850-speed-problem.html

Basically, I have to enable Bandwidth Limit and set a very high number, and then disable it.

I then have to do the same is QoS..

I also have to make sure the default firewall rules are enabled. If I turn off everything in the firewall section, it runs slow again.

It's hard to pinpoint exactly what makes the difference, I just know I have to test the speed each time I change something in case I've "upset" it... It's like the router still uses the parameters in QoS and Bandwidth Limit, even though it's disabled, and there's some strange interaction with other settings, such as the Firewall.. Or maybe saving those other settings upsets other settings... !

With a bit of messing about, I can get the throughput up to 65 / 70 mbps .. which is still not as fast as the **cheap** TP-Link, which is stable at 75 mbps.

Sorry, this is just ridiculously flaky. I'm a freelance software engineer; I'd never be happy with something that behaves like that. I wouldn't have customers for very long especially as I'm involved with mission critical systems.

To expand why I'm a bit frustrated about this: The previous Draytek I had (2820) went wrong on me, it just kept rebooting. The 2850 did that after a while too, but I re-flashed it, which fixed it.. I bet the 2820 would have been too, but I needed it to work NOW (I use it for work) so I replaced it immediately. So basically I've shelled out nearly £400 for what is being shown up speed / stability wise by a £35 TP-Link. Unreal.

I am looking elsewhere for a router, which is really unfortunate because otherwise it is a great router.

To be fair to DrayTek , you are using an old legacy model that last had a formal firmware update in December 2016.[security patch Jan2017]

While the 2850 worked with VDSL it does not work with Vectoring or G.INP . G.INP is running on many fibre cabinets and your hardware/firmware needs to be compatible, otherwise you will see connection issues.

I use a Vigor130 modem , the ECI cabinet I connect to obviously doesn't like the recommended BT firmware , I see constant port errors and session drops , moving to the alternative firmware offered by DrayTek there are no port errors and sessions last for many months.

People connected to Hauwei cabinets have no issue.

I am connecting through an Openreach modem, any incompatibility with the cabinet should be mitigated by that surely?

Also I don't buy the argument that it is a couple of years old and therefore it's fine for the firmware to be flaky. I've been a freelance software engineer for 15 years operating purely on word of mouth, and believe me if I had that attitude I would not have customers for long. One of my oldest customers has 1000's of proprietary vehicle trackers that have been out in the field since 2005! The last firmware update was probably around 2009. They still accept settings without getting confused, the GSM modems still work with the networks, and they never need re-flashing. Things CAN be designed to last more than 5 minutes..

The kind of bugs we are talking about here are not hardware compatibility issues, it is basic software settings / logic processing issues.

MarkOSSL wrote:
I don't buy the argument that it is a couple of years old and therefore it's fine for the firmware to be flaky.

That wasn't his point. It's more than a couple of years old probably, but since its release, BT upgraded their cabinets to support new technologies which the V2850 chipset did not support (e.g. G.INP). DrayTek did have an upgrade programme for some time for V2850 owners but not any more. That said, this wasn't your issue anyway as you're using the BT modem. On WAN2 (Ethernet) maybe it's an MTU issue, or you have DoS protection or Hardware Accelleration turned on.

A Vigor 2862 would get around it because you can connect it directly to the line, but don't give up on the current hardware - it might just need settings.