powercut at about midnight for about a second so your correct, so looks like il be getting 58mb max on sync and about the 3.3db on the upstream, is that alound on openreach cabinets as i thought it was only downstream that could drop and the upstream should always stay at 6?
j0hn83 (fountain of knowledge)
Fri 15-Jan-21 02:49:53
Re: Comparing 2x line stats? new and old? faster maybe?
There's a target SNRM set by the DLM and there's the current SNRM. Also known as the target noise margin and current noise margin.
Your line has a target of 6dB (up and down) but it's running lower than that.
You connected at the 6dB target before other lines on the cabinet. As those lines weren't there you synced higher.
The other lines connected after you (likely within a minute). The noise the other lines create (known as crosstalk) knocks the current SNRM (noise margin) down.
The max rate reported knows the target SNRM is 6dB so the max rate is still low.
If/when the DLM lowers the SNRM target to 5dB the max rate will increase.
Your line jumping straight from 6dB to 3dB and the max data rate staying low suggests a power cut or the cabinet rebooting.
The DLM only ever moves the target SNRM in 1dB steps.
The upstream is always a fixed 6dB target (some modems target 6.3dB)
Register (or login) on our website and you will not see this ad.
Interleaving adds a minimum 8ms latency and knocks about 10% of the potential sync.
With interleaving enabled the max rate reported is exaggerated and incorrect.
If the line went to fastpath sync should go up, max rate down, latency would drop by 8ms.
Only the latency changed, by what looks like less than 8ms (hard to tell on a BQM).
It could just be a change of routing from the ISP.
Pages in this thread: 
Print Thread
j0hn83
