In reply to a post by xreyuk123:

Thanks guys, I'll try and figure out how far I am from the exchange. Do I just use the roads as an estimate?

I forgot to say - distance from the exchange is irrelevant. It is distance from the FTTC cabinet via the PCP (phone) cabinet that matters.

No problem.

I've tried running the test again, and here are the results. Again I can't seem to be able to get my IP Profile information. Again, this was the good browser, so there's evidently a problem with my upload speed too.

1. Best Effort Test:

Download Speed : 36.37 Mbps

2. Upstream Test:

Upload Speed : 2.62 Mbps


Your speed test has completed and the results are shown above, however during the test an error occurred while trying to retrieve additional details regarding your service. As a result we are unable to determine if the speed you received during the test is acceptable for your service. Please re-run the test if you require this additional information.

My TBB Ping graph has been pretty bad tonight, but I was downloading stuff constantly from 8PM up until about 10PM. The ping has dropped lower though, from 32ms to about 24ms.

http://www.thinkbroadband.com/ping/share/06b89dffb48...

It's a short graph, which is due to me having some electrical work done earlier today, which mean the modem was off, and has been resented around 4-6PM.

Edited by deleted (Sun 15-Jun-14 22:18:36)

There's been a bit of stuff about several users not being able to get to the Further Diagnostics recently. But take my word for it about what the Current line speed should be for a 49.9Mbps sync.

However if the modem has been off, it's probable the 49.9Mbps is no longer correct. The Current line speed may reflect the new reality.

I would ask them to check the sync, IP Profile and Current line speed.

Thanks Roberto, I'll ask them to do that.

It's a shame that when I go back to my parents, that I'm actually browsing quicker on an ADSL2+ connection, and have half the ping time (however I know that connection isn't interleaved).

The current line speed has been set at 40Mbps since the second day, and has never changed. So it was at 40Mbps, even when the staff told me it was 49.9Mbps. However I understand that could have changed, the resync was what actually improved my ping times.

I've also seen a couple of customers on the Plusnet forum saying they've been set on 40/10 Plusnet's end, despite being on the unlimited package, which is supposed to be 80/20.

Edited by deleted (Sun 15-Jun-14 23:36:20)

The upstream speed of 11Mbps shows you are on 80/20, as does the 49.9. However it looks as though the Current line speed was incorrectly set at the start.

The ones you have seen would have had estimates below 40Mbps, so were provisioned on 40/10 but unlimited allowance. A bad move by Plusnet.

No problem. I'll ask them tomorrow if there is anything that can be done. From what I've seen on the forums, my details may take up to 14 days to show correctly on the BT Wholesale Speedtester anyway.

Thanks for all your help, I'll let you know what they do

Edited by deleted (Mon 16-Jun-14 00:02:58)

Hi,

Plusnet have adjusted some things today. They said after the resync for the power off, I'm now running at 43.4/10.9 with a current speed of 41.8Mbps on the Plusnet website. They said they'd had the profile set at 40Mbps their end.

It appears that the resync caused interleaving to be turned off, as the ping times went back to around 20ms, however, this morning I can see from my graph that interleaving has kicked in again. There was no packet loss shown on the ping graph, but I suppose the circuit could still be running errors?

It's my ping times that are annoying me, because my browsing expeirence is slower than around the corner at the parents, which has a 13-16ms ping to bbc on ADSL2+.

Here is my graph.

http://www.thinkbroadband.com/ping/share/42ac8c8f06d...

Does DLM ever take interleaving off, or force resyncs to a higher speed, or once DLM has set parameters is that it?

Edited by deleted (Mon 16-Jun-14 12:01:55)

Does DLM ever take interleaving off, or force resyncs to a higher speed

It can happen, and has happend on my line a couple of times (when DLM intervened due to a physical fault on the line)

DLM watches the error rate on the line, although strictly it watches the "ES" count (errored second), and calculates an "MTBE" value over 24 hours (mean time between errors). Errors cause packets to be thrown away - causing packet loss on the ping graphs, or causing retransmission of packets on a download (which also makes the download appear slightly slower).

If the ES value gets too high over 24 hours, DLM intervenes, or increases the intervention. If the ES value gets "too low", then it reduces intervention, or removes it. Expect increased intervention to occur after 1 day of errors, but only expect a reduction to happen after 1-4 weeks of reduced errors.

The first step of intervention is almost always to turn on FEC (forward error correction), with the aim that this will reduce the error rate. Depending on the level of intervention, FEC alone can add an overhead of anywhere between 10% and 30% of your line's bandwidth - so you can usually count on a reduction in headline sync speed (and all download speeds) of around 20%.

(You can get less of a drop in speed when adding FEC, but only if your line is capable of more than the package speed; an 80/20 line might not lose any speed at all if it is so short that it is capable of 100/30)

However, FEC alone isn't effective enough against noise on the line - so DLM always turns on interleaving too; it is the combined effect of FEC and interleaving that works best at coping with errors. When interleaving is turned on, it adds latency to your connection - and the default amount (for downstream interleaving) is 8ms.

If your line turns out to be bad upstream, and interleaving needs to be added there too, the combined delay usually ends up around 12ms.

So...
DLM *might* remove intervention if whatever causes your packet loss goes away. But I wouldn't expect it to. If your error rate isn't reduced enough, it could turn the intervention up higher.

In reply to a post by xreyuk123:

It appears that the resync caused interleaving to be turned off, as the ping times went back to around 20ms, however, this morning I can see from my graph that interleaving has kicked in again.

I experienced the same thing at my previous home, but with more noticeable errors.

On first connection (on the then-available 40/2 package), I got a 40/2 sync but also got about 4% packet loss. This packet loss was visible on the ping graphs, but also dropped my download speeds by about 10%.

Two days later, DLM intervened. The sync speed dropped by 3Mbps, the errors disappeared, the ping graphs showed the added latency. But noticeably, the download speed didn't change.

1st install: http://postimg.org/image/vojahjizn/
DLM intervention: http://postimg.org/image/rgoi8shk3/

My line was reset after another couple of days, to adjust my upstream speeds to 40/10 (this was before the days of 80/20). That also reset DLM, so I got to see the same process a second time.

That line stayed susceptible to the same errors throughout its life, at least until the frequency bands were shifted around in preparation for 80/20. That shift gave my line enough breathing space to achieve 40/10 without DLM intervention.

There was no packet loss shown on the ping graph, but I suppose the circuit could still be running errors?

Oh yes.

My current line is running without DLM intervention, but still regularly shows around 8000 CRC errors per day and about 700 ES's per day. Each of those 8000 CRC's could show as a dropped packet in the ping graph, but they usually don't. My ping graphs may (on very close inspection) show 4 or 5 red pixels. Almost invisible...

Both lines that I have at home and at work have fluctuated between no interleaving, and varying levels of interleaving. One runs about 36 to 40 sync, the other about 42 to 47. I don't really notice any problems browsing with things being pretty fast really.