Maxed And Confused

[#1]

I was put on Max about 11 days ago (I'm not sure when, except that the e-mail from +Net on 15/09/08 said that my broadband had 'recently' been upgraded). The e-mail said "We estimate that your new speed should be around or above 3500kbps" (I was previously on a stable 1MB connection).
I expected some fluctuations and drop-outs during the initial period (and got some), but I'm wondering if there's something not quite right.
I've been doing a number of speed tests (+Net's & BTs). My router always connects at > 5MB, yet since last weekend I've had trouble getting the download speed up even to the level it was on the old setup (i.e. 1MB). It seems to vary between about 710Kbps and 990Kbps, irrespective of what time of day I test (my highest figure - over 4Mbps - was last Sunday evening).
My router's current readings are:
Connection speed (down/up): 5344/448 kbps
Line attenuation (down/up): 44 db/13 db
Noise margin (down/up): 3 db/20 db
My latest +Net speed test shows the download throughput as just under 1MB, and 'Connection settings' on the Member Centre says that my current speed is 1000kbps (supposedly based on my sync speed). BT's speedtests tend to show lower figures (720 - 870 kbps)
Am I missing something here? I don't see a lot of point in having a connection where the speed varies and seldom even gets up to the stable level I was getting before. Is this as good as Max is likely to get for me?

[#2]

Looks like your IP profile (the 1000 figure if this is from the 'high speed broadband' page) has not been updated from when you were on a 1Mbs connection and it is this that is limiting your speed. Normally BT send PN a Bras profile after the Max training period which includes the IP profile (speed allowed through your connection) which PN should update on their systems.
What IP profile is the BT speedtest giving you? Is this also around 1000?

Just raise a ticket, post your router stats  and say your profile has not been updated and it should be sorted fairly quickly.

[#3]

Quoth Peter Vaughan:

Quote

What IP profile is the BT speedtest giving you? Is this also around 1000?

That's been either 4000 or 4500 throughout as far as I can remember.
Incidentally, just done another test (BT) and the speed was about 3.4M!
Current router stats are:
ADSL Link  Downstream  Upstream
Connection Speed 5536 kbps 448 kbps
Line Attenuation 44 db 13.5 db
Noise Margin 0 db 21 db
I'll hold off another day or so on raising a ticket in case BT are being a bit slow passing the info on ("What? BT? Do something like that? Surely not?"  ;D)
Incidentally, what would constitute a 'good' Line Attenuation and Noise Margin figure?
Many thanks.

[#4]

Quote from: thejudge

what would constitute a 'good' Line Attenuation and Noise Margin figure?

Line attenuation is a measure of the length of your phone line so it's generally just what it is.
Anything under 30dB (around 2km) will get you the full 8meg on ADSL Max or near enough to not matter.
Noise margin is normally set at 6dB downstream unless you have lots of errors in which case it's set higher (and you run slower).
Your figure of 0dB is probably misreported.
(upstream attenuation and SNR are normally not an issue)

[#5]

Quote

Anything under 30dB (around 2km) will get you the full 8meg on ADSL Max or near enough to not matter.

Well, I'm about 3.2km from the exchange (allowing for wiring routes, etc.), so 44dB would be about par for the course.

Quote

Noise margin is normally set at 6dB downstream unless you have lots of errors in which case it's set higher (and you run slower). Your figure of 0dB is probably misreported.

Must have been a slight blip - my router's now showing 3dB. As it was showing that yesterday as well, I'll assume this is a more usual figure for the line, and not a bad one at that!
Thanks.

[#6]

Noise margin does vary, but 3dB is very low on BT equipment.
If you resync the default target would normally be 6dB or higher; 3dB is strangely low.
My line is currently at 4.1dB but I'm not connected to BT exchange kit and my default is set deliberately low at 3dB, something that shouldn't apply to you.

[#7]

Well, it's still showing 3dB now, and I don't intend to knock it!
I don't intend powering off the router anytime in the next year or two either! 

[#8]

It's probably just SNR drift since it last synced - it probably did sync at 6dB, and it can vary during the day.
Or you have a Netgear DG834 router which can show lower than actual SNR figures. In theory if your SNR is 0 you have no signal so most likely being misreported.
What does it say on the high speed broadband page now. If you were getiing a 3Mbs download speed then this may have changed.

[#9]

I haven't repowered or rebooted the modem since my last post, and the noise is now showing at 7dB.
Yes, it is a DG834, so that probably explains it (it also explains why that reading went negative yesterday!).
I'm still getting 3500 - 4000 on the speed tests (BT the lower figure), but the HSB page still shows 1000. I'll wait another day or so before reporting it.

[#10]

I was getting good download speeds (having left the router on) until we had one of our power cuts last night. When I say one of "our" power cuts, I mean that weak backup circuits mean that the power goes off, then comes back for a few seconds, then goes off again, then comes back on for a few more seconds before going off again for a while (45 minutes in this case). It then came back on and did exactly the same thing. A stable supply wasn't restored for another hour or so.
Result? This morning my download speed is back below 1000.
Thanks a heap Scottish Power! 

[#11]

I bought a UPS (similar to one of these as our mains supply was as bad as yours sounds).
It basically keeps everything powered up during an outage and then shuts down gracefully if the power is off for too long.  It stops the on/off/on/off that you're getting.  (You're lucky Scottish Power's antics only dropped your broadband speed - they managed to kill my PC altogether hence the UPS!).
I've since changed model as I've now got more running off it but the one linked to served me well!

[#12]

Thanks Paul, I might look into that.
Ticket 26484193 raised for the IP profile issue.

[#13]

Quote from: thejudge

Ticket 26484193 raised for the IP profile issue.

just checked the internal line speed profile,already updated properly
I'd advise keeping your router always on. if you switch it Off and On many times a day it will lower the sync rate and therefore the IP profile.
glad you're getting more that 3500kbps now

[#14]

Thanks Rami, it seems to be consistently in the range 3500 - 4000 now.