She'll not take any more, Captain !

Nice surprise this morning, ran the BTw speed tester and wondered why I had 74meg downstream profile, JDSU confirms sync (always a little lower than the modem manages) at 73468/20000,

Interesting also, as the tester had shown a max achievable rate of 77meg.

I have not asked for an upgrade, and the only other confirmed case of 80/20 I know, was contacted by BT retail telling him he was going on a trial....... nothing similar received here.

So it looks like that's it for my line, finally topped out at 74 meg. Not bad, starting back 12 odd years ago with 512Kbps and a USB modem.

Shame I haven't the equipment at this end to make the most of it..........



1. Best Effort Test: -provides background information.

Download Speed
24 Mbps

0 Mbps 72.93 Mbps
Max Achievable Speed

Download speedachieved during the test was - 24 Mbps
For your connection, the acceptable range of speedsis 12 Mbps-72.93 Mbps .
Additional Information:
IP Profile for your line is - 72.93 Mbps

2. Upstream Test: -provides background information.

Upload Speed
13.88 Mbps

0 Kbps 20 Mbps
Max Achievable Speed

Upload speed achieved during the test was - 13.88Mbps
Additional Information:
Upstream Rate IP profile on your line is - 20 Mbps

...noticed also that the downstream sync profile is now lower than this morning, settlig down maybe.

Has anyone else had this unrequested hike ?

Edited by Zarjaz (Sun 08-Apr-12 20:34:47)

In reply to a post by Zarjaz:

So it looks like that's it for my line, finally topped out at 74 meg.

Vectoring might give you more

?? What's 'vectoring' ??

Short of recrimping every connection between here and the cab, and making sure the twist is tight in said joints, I suspect that's it, sync wise.

until they tweak the VDSL technology again.

www.alcatel-lucent.com/vdsl2-vectoring/
http://www.ospmag.com/issue/article/vdsl2-turning-co...

OK, I can see that there's a little room for occupying more bit's per bin up the top end, but ....

I had thought that when I did 40/10 then it would go higher, now I don't get the full 80, that must be it ??

Does vectoring require any hardware replacement? Or is it just a different code/method of sending the signal?

that's it with the current frequency profiles and technology, I agree. If vectoring allows noise cancellation to give you more effective SNR then the speed can go up.

Then you need a second line to double it with bonding

In reply to a post by Zarjaz:

So it looks like that's it for my line

When anyone says something like that I'm always reminded of the dial-up days, when ~50kbps was regarded as close to the maximum possible, with learned quotes about line bandwidth and Shannon's theorem to back them up.

Now I can download 200 times faster than that down the same bit of wire, and nearly 1,500 times with the aid of a bit of fibre

Does vectoring require any hardware replacement?

I wouldn't think so, from my (limited) understanding. Or maybe it requires an add-on unit to analyse the noise and introduce the anti-noise. Might be proprietary too, so if you backed the wrong vendor you don't get it, but hopefully it'll be standardised.

http://www.assia-inc.com/DSL-technology/DSL-knowledg...


From what i've been reading, a Line with vectoring Zarjaz will take your speed of 74 to well over 100

Edited by Moradin (Sun 08-Apr-12 11:32:20)