User comments on ISPs
  >> Sky Broadband


Register (or login) on our website and you will not see this ad.


  Print Thread
Standard User Mellors
(newbie) Sat 19-May-12 19:35:51
Print Post

Slow speed?


[link to this post]
 
Hi, I'm moving into a house that's got Sky BB with no chance of changing providers and FTTC not an option for the time being.

The predicted speeds were 7-14Mb but they're only just getting 5Mb. And judging by the router stats it's quite a bit slower than it should be.

ADSL Link Downstream Upstream
Connection Speed 6141 kbps 796 kbps
Line Attenuation 44.5 dB 24.9 dB
Noise Margin 3.3 dB 10.8 dB

I've tested it with the master socket and the stats are pretty much identical so I'm not really sure what to do. I don't want £100+ charge if they send a BT engineer out and find nothing wrong or if it's a problem with the internal wiring.

And I know 5Mb isn't the end of the world, I'm just used to 50Mb but VM aren't available here, not that I'd ever go with them again anyway.

Any help would be greatly appreciated.
Standard User Deadbeat
(knowledge is power) Sat 19-May-12 20:22:34
Print Post

Re: Slow speed?


[re: Mellors] [link to this post]
 
Off the top of my head, your 44.5dB attenuation should get you around a 7.5M sync with around 6.7M throughput at an SNR of 3dB.
Standard User Mellors
(newbie) Sat 19-May-12 20:42:52
Print Post

Re: Slow speed?


[re: Deadbeat] [link to this post]
 
Hmmm, just rebooted the router. Now these are the stats.

Connection Speed 6142 kbps 796 kbps
Line Attenuation 44.5 dB 27.6 dB
Noise Margin 6.8 dB 10.5 dB

SNR more than doubled with a less than negligible change for the sync speed.

On another connection I have access to that is an extra 1.5 miles away from the exchange by road has an attenuation of 63 and SNR of ~6 and has a sync speed of 52xxkbps. That connection also has much lower and more stable pings with the max being 1ms higher than minimum when it's idle.

On this Sky connection the pings are about 30ms higher.


Register (or login) on our website and you will not see this ad.

Standard User Deadbeat
(knowledge is power) Sat 19-May-12 20:57:31
Print Post

Re: Slow speed?


[re: Mellors] [link to this post]
 
A 63dB attenuation figure will only see around a 2M sync.
Standard User Mellors
(newbie) Sun 20-May-12 17:17:14
Print Post

Re: Slow speed?


[re: Deadbeat] [link to this post]
 
This is the other connection and it's 2.8 miles to the exchange by road so the line will be even longer.

Downstream Upstream

Data rate(Kbps)
5334Kb 1057Kb

Noise Margin
6 5

Output power(dBm)
121 192

Attenuation(dB)
64 30

And the Sky connection is 1.1miles by road and that includes the road where the cab is but it will still likely be longer than that.

I just can't see how a difference of ~20 in attenuation can result in a sync of only 800kbps higher. I know .9SNR wouldn't make that much of a difference.
  Print Thread

Jump to