In reply to a post by broadbandjockey:

I've just moved house, and I'm very close to the FTTC cabinet, syncing at close to 78 Mb/s
However, real speedtests etc, and even attempting ftp transfers as tests never get above 60 Mb/s.

I'm only syncing at just above 73 Mb/s and my speed test results are typically around 67 Mb/s.

Are you testing over a wired or wireless connection? The latter can often yield worse results than wired. Alternatively it could be a hardware issue, configuration issue or just a poor ISP.

Edited by Andrue (Thu 29-Aug-19 15:56:52)

In reply to a post by candlerb:

In reply to a post by broadbandjockey:

Yep, just over 3 mins for 1GB, so just under 60 Mb/s?

So the throughput including TCP/IP headers is about 47.7 Mbps.

The 200 mb file which i used regularly takes 28 seconds which according to the times next to it is slightly below 60 Mbps (it should take 27 seconds)

Are you telling us all the times given with each file are wrong?

.

In reply to a post by Chippy_Tea_:

Are you telling us all the times given with each file are wrong?

Seems so - they're not even consistent with each other.

For example, it says that 200MiB takes 27 seconds @ 60Mbps, but 1GiB (1024MiB) takes 3 mins = 180 seconds.

FWIW, I calculate:

200MiB @ 60Mbps to be 200*1024*1024*8/(60*1000*1000) = 27.96 secs
1024MiB @ 60Mbps to be 1024*1024*1024*8/(60*1000*1000) = 143.17 secs

Could be rounding errors - although 143 secs is closer to 2 mins than 3 mins.

Makes note to either add a note that timings are approximate or display them to the precise second.

In reply to a post by MrSaffron:

Makes note to either add a note that timings are approximate or display them to the precise second.

To be honest i usually just click the file and see where the download speed settles out at after a few seconds for me its usually around 60M/bs.

Edited by deleted (Thu 29-Aug-19 20:52:43)

In reply to a post by RobertoS:

Do Plusnet still use their "Current line speed" setting? I think it is still available using this link, but may not be.

That used to get stuck at times in the past, but if you've done a few re-sync's that's unlikely to be the problem.

Well, as I said a few days ago, I've not rebooted since the day the service was connected, two months ago.

I've just done a reboot now, and now I'm getting, 68-69 ish on speedtests, (via LAN, everything else disconnected) I'm syncing at 75.8, so probably not far off the theoretical max ?

Can someone explain what and how 'Max Obtainable' sync is calculated ?

In reply to a post by broadbandjockey:

In reply to a post by RobertoS:

Do Plusnet still use their "Current line speed" setting? I think it is still available using this link, but may not be.

That used to get stuck at times in the past, but if you've done a few re-sync's that's unlikely to be the problem.

Well, as I said a few days ago, I've not rebooted since the day the service was connected, two months ago.

I've just done a reboot now, and now I'm getting, 68-69 ish on speedtests, (via LAN, everything else disconnected) I'm syncing at 75.8, so probably not far off the theoretical max ?

Can someone explain what and how 'Max Obtainable' sync is calculated ?

That's the maximum sync speed possible if the router and DSLAM agree to ignore all the rules. Typically that would result in an unstable connection that failed in short order. To avoid that the router and DSLAM use various rules to adjust the parameters of connection trading off speed against stability.

Under some circumstances the current sync speed can be lower than is strictly necessary for stability but in practice what has been negotiated is usually the highest and most reliable speed possible. This will often be lower than the highest possible speed but is intended to try and achieve 24/7 connectivity.

Edited by Andrue (Sun 01-Sep-19 18:56:02)

In reply to a post by Andrue:

Under some circumstances the current sync speed can be lower than is strictly necessary for stability

One example is if you live very close to the cabinet. VDSL2 profile 17a is capable of 100Mbps, but since the product is defined by OpenReach as having a maximum sync speed of 80Mbps, they limit it to that - even if higher speeds would be reliable.

In reply to a post by candlerb:

In reply to a post by Andrue:

Under some circumstances the current sync speed can be lower than is strictly necessary for stability

One example is if you live very close to the cabinet. VDSL2 profile 17a is capable of 100Mbps, but since the product is defined by OpenReach as having a maximum sync speed of 80Mbps, they limit it to that - even if higher speeds would be reliable.

So in other words the router is extrapolating the SNR vs Sync curve to the threshold point?

Makes sense, that's why then my son's max obtainable is 62, but the sync speed is exactly 40, because he's on an 'up to 38' package. If he went for an up to 76 package, he'd probably be syncing at 57ish?

Something like that, though you don't have to be that close to the cabinet to get max obtainable greater than 80/20. I sync at 79999/19999 which I presume is the full 80/20 with a max obtainable of something like 89/23. My mother is even closer to her cabinet getting the same 79999/19999 with an even higher max obtainable. However I am sufficiently far away from the cabinet that I can't get G.fast despite the cabinet being enabled. I am sure profile 35b would have made much more sense that G.fast.