Kitz Forum

Broadband Related => FTTC and FTTP Issues => Topic started by: 111888 on September 27, 2023, 06:48:51 PM

Title: a question about dlm on vdsl
Post by: 111888 on September 27, 2023, 06:48:51 PM
my latency keeps going randomly over 100ms, when it used  to stay around 8ms.

can dlm cause this to happen on unstable lines?
Title: Re: a question about dlm on vdsl
Post by: g3uiss on September 27, 2023, 07:03:26 PM
Is this following a resync ?
Title: Re: a question about dlm on vdsl
Post by: 111888 on September 27, 2023, 07:56:13 PM
Is this following a resync ?

This is followed by moving over to a sogea broadband only.
Title: Re: a question about dlm on vdsl
Post by: g3uiss on September 27, 2023, 09:22:27 PM
But does the random burst follow a resync ?
Title: Re: a question about dlm on vdsl
Post by: 111888 on September 27, 2023, 11:09:09 PM
But does the random burst follow a resync ?

no
Title: Re: a question about dlm on vdsl
Post by: tubaman on September 28, 2023, 08:30:17 AM
This is followed by moving over to a sogea broadband only.

This is more likely to be the cause as it won't be DLM doing this.
Title: Re: a question about dlm on vdsl
Post by: 111888 on October 01, 2023, 12:33:20 AM
I had a dlm reset, the first 24 hours it seemed fine and now I am having issues again.

Also I want to ask why do people say over here that vdsl routers need to have bitswap on but my draytek router clearly shows bitswap is off on my line. only trellis is on.
Title: Re: a question about dlm on vdsl
Post by: kitz on October 01, 2023, 08:42:45 AM
dlm should not cause delays such as above.   8ms low >16mis high.   They would also be static.

I do believe there are some routers that misreport bitswap. Have you tried turning it on?

>> Also I want to ask why do people say over here that vdsl routers need to have bitswap on <<
Bitswap should be on.  Depending upon your line it can help instability from small SNR fluctuations. Bitwsap allows the modem to reuse tones that may have previously been marked as having no SNR... thus keeping the line up for longer.
See What is bit swapping (https://kitz.co.uk/adsl/adsl_technology.htm#bit_swapping)