cancel
Showing results for 
Search instead for 
Did you mean: 
Distinguished Sage
Distinguished Sage
514 Views
Message 21 of 50

Re: Noisy line and terrible upload speed

Look forward to your next update after your phone call



If you like a post, or want to say thanks for a helpful answer, please click on the Ratings 'Thumbs up' on left hand side.
If someone answers your question correctly please let other members know by clicking on ’Mark as Accepted Solution’.
0 Ratings
Reply
BeardyDave
Contributor
465 Views
Message 22 of 50

Re: Noisy line and terrible upload speed

BT didn't actually ring me at the date and time arranged, they tried to call a few times on the following days while I was out. I don't really have time to keep messing around calling them so I just left it and kept monitoring my line stats over the last few weeks.

 

My upload speed has stayed pretty constant at around 5-5.5Mbps but my upload has slowly increased to around 44-45Mbps. My ping latency has also significantly improved (reduced) and is now around 15-25ms depending on the time of day etc. So everything seems to has pretty much retured to where it was shortly after my connection was first enabled:

 

07-12-2015.png

 

I had to switch off my HH5 for a bit yesterday to rearrange some cables and being paranoid about my line resyncing at a **bleep** speed I checked my line stats again. I seem to have some slightly odd results:

 

1. Product name: BT Home Hub
2. Serial number:
3. Firmware version: Software version 4.7.5.1.83.8.204.1.11 (Type A) Last updated 04/07/15
4. Board version: BT Hub 5A
5. DSL uptime: 0 days, 17:44:14
6. Data rate: 5499 / 48178
7. Maximum data rate: 5813 / 47521
8. Noise margin: 6.2 / 5.8
9. Line attenuation: 29.4 / 22.6
10. Signal attenuation: 28.7 / 21.0

 

These are my stats from last week:

 

1. Product name: BT Home Hub
2. Serial number:
3. Firmware version: Software version 4.7.5.1.83.8.204.1.11 (Type A) Last updated 04/07/15
4. Board version: BT Hub 5A
5. DSL uptime: 4 days, 01:06:40
6. Data rate: 5733 / 47570
7. Maximum data rate: 5978 / 47398
8. Noise margin: 6.1 / 6.0
9. Line attenuation: 29.3 / 22.5
10. Signal attenuation: 28.6 / 20.9

 

My download data rate is slightly higher than my max data rate and my download noise margin has dropped to 5.8 when it was beteen 6 and 6.2 a few days ago. I know the "targit" noise margin is 6 but I've still not been able to establish whether higher or lower numbers are better. There are lots of conflicting oppinions on this. I also have no idea what line attenuation or signal attenuation are and again whether high or low numbers are good. I'd be really gratful if someone can clear this up and tell me if my stats are good or bad.

0 Ratings
Reply
Distinguished Sage
445 Views
Message 23 of 50

Re: Noisy line and terrible upload speed

Your stats are fine
0 Ratings
Reply
BeardyDave
Contributor
437 Views
Message 24 of 50

Re: Noisy line and terrible upload speed

Thanks, that's good to know. Hopefully things will remain consistant now.

 

I would like to know a bit more about the stats though, like how I can have a faster data rate than the maximum data rate and exactly what the noise margin, line and signal attenuation mean, what they're measured in, whether high or low values are desirable and what the upper and lower limits are?

0 Ratings
Reply
Distinguished Sage
433 Views
Message 25 of 50

Re: Noisy line and terrible upload speed

The Max data rate changes constantly noise margin is measured in dBs and changes slightly over a 24 hour period and yours is varying by an average amount the default is 6dB as to the attenuation figure again measured in dB's and are related to the distance and line quality between your house and the street cabinet there is no upper and lower limits in the case of attenuation
0 Ratings
Reply
BeardyDave
Contributor
429 Views
Message 26 of 50

Re: Noisy line and terrible upload speed

Great, thanks.

 

So on the noise margin, does a lower number mean less noise is present on the line?

0 Ratings
Reply
Distinguished Sage
Distinguished Sage
426 Views
Message 27 of 50

Re: Noisy line and terrible upload speed

Its nothing to do with the actual line noise.

 

The lower the margin, the closer the connection is to its maximum capacity.

 

A certain noise margin is needed, to allow for variations in line quality during the day, otherwise if line conditions deteriorated too far, then the connection would drop.

 

The nominal value is normally 6dB, but this may drop during the evening as electrical interference impacts on the line performance

 

A very high noise margin indicates that the full potential is not being realised. This could be as a result of a previous fault condition, and the DLM has reduced the connection speed to make the line stable.

 

 

Another way to think of it is to imagine two people talking in a room. If the room is empty the noise margin is high, and you can hear each other clearly and talk fast and clear.

 

As the room fills up with other people talking, the noise margin drops, and it becomes difficult to communicate.

 

If somone turns on some loud  music, the noise margin is virtually zero, and you cannot hear each other.

 

Highlighted
BeardyDave
Contributor
417 Views
Message 28 of 50

Re: Noisy line and terrible upload speed

Thanks, that's starting to make a lot more sense now. I didn't understand wy it was called noise "margin" but I think I get that now. I guess it's a bit like when you say "a margin for error". If you give a big margin for error in something, your not confident in the results. Have I got that right?

0 Ratings
Reply
Distinguished Sage
Distinguished Sage
414 Views
Message 29 of 50

Re: Noisy line and terrible upload speed

Yes, a margin for error is a good way of putting it.

 

If someone should be getting a good connection speed, and is not, then looking at the noise margin can give a good idea what is wrong.

 

A much slower than expected connection speed, and a low noise margin, usually indicates a line or internal wiring fault.

 

Which is why the regulars on here, ask for information about expected speeds, and actual speeds and noise margin, as that helps to identify what could be wrong.

 

 

BeardyDave
Contributor
400 Views
Message 30 of 50

Re: Noisy line and terrible upload speed

Thanks, that makes a lot of sense.

 

Many thanks to everyone who contributed!