Hi all,

Back in April I had the transition from BT SmartHub to Vigor 2860ac.

Initially the 2860 was syncing at 45Mbps up, 8.5Mbps down (BT Infinity 2) as the BT Homehub had for a long long time (years prior).

I have however over the last couple of months dropped to syncing at 39Mbps down (dropped to 42 first). Snr margin used to be 6 and 6. Now 9 for download.

The BT call center (frustration that they are) says everything is OK. The Homehub now syncs at the same speed if I try that. I am not sure if I have been unlucky with getting some degradation introduced on my line or if the performance of the 2860 has caused my max obtainable rate to drop - actually I see from the stats the attainable rate is still 48Mbps

I am using the 3.8.4.5_BT firmware.

I do not think I have vectoring on the line. Is anyone seeing performance improvement using the specific non-vectoring firmware? Why would my sync speed be so far from the attainable rate?

Any other suggestions please?

Hi,

Looking at your details you are experiencing a similar situation to myself, although I am a lot closer to the cabinet it seems and I do get a sync of 74999 used to be 76000.

I do notice you have quite a lot of upstream errors, ES are the important ones as far as BT dynamic line management (DLM) is concerned. I also suffer a similar number on the upstream. I never had this problem with broadcom based modems such as the BT Home Hub.

There is something not quite right with the BT firmware for the 2860. I tried installing the Vector 4 version of the standard firmware (without the BT on the end) and had better downstream SNR which was 6 with the BT firmware version. I would recommend trying the alternative firmware (V4) which has different modem code. This seems to allow a higher attainable rate and give you a bit more headroom on the SNR.

While your SNR is 6, this is generally the standard level for Infinity 2, well for most people anyway. While this is 6 you will not really get faster speeds. Updating the firmware may give you a little faster but it won't be a huge amount.

I've come to the conclusion that the Lantiq chipset in the Draytekk models, although quite steady, do seem to cause more CRC errors than I would have liked and also not able to sync at quite the same level as a broadcom based modem. Apart from that i'm happy with it.

I now wonder if all Draytek owners connected to a broadcom based cabinet experience a consistent number of upstream ES errors.

Thanks for the reply.

Did you try any of the other vector firmwares before concluding 4 worked best for you?

Vector 1 doesn't support G.INP (enabled on my line) so not an option.

Vector 2 and 4 both state different VDSL modem codes to the BT fw.

Lastly how did you determine what type of cab you are connected to?

Hi,

You are on a broadcom based cab (BDCM) is shown as the Vendor ID on your screenshot.

I wanted G.INP and Vectoring capability and not the same modem firmware as the BT version. I noticed firmware 4 had the highest update, and also read someone's post saying that they got the highest speed with firmware 4.

So I went with it, and it seems to maintain a higher attainable rate which does not gradually lower itself and maintains a constant SNR.

In fact I've just tried V4 of 3.8.5.6 I found when clicking the firmware update button from within the Router. Couldn't find it on their website yet so haven't seen the change log. Seems to be working well too... at least no worse.

I'm giving 3.8.4.5_VT4 (579F17) a go as recommended.

My downstream attainable rate is up to around 50,828 Kbps (various marginally). I'm still on 39,998 Kbps down due to the 9db SNR margin. Fingers cross that will lift in time (although it hadn't before so I haven't high hopes).


If I don't see an improvement and I can find a recommended VDSL2 modem with a Broadcom chipset that I can access line stats on, I will be giving that a go.