TalkTalk to Zen Latency DSLAM

Hello. I just recently switched to zen unlimited fibre 2 from TalkTalk 80/20 on the 10th (yesturday) however i have noticed my latency has doubled comparing to TalkTalk .

Is this normal behavior for a line switch from TalkTalk to Zen WBMC?

Also did they switch me from the Exchange iself or did they change me via the local street cabinet. The switch had taken no less then 5 minutes as the DSL line went out, They did also take my TalkTalk number also.

TalkTalk status line
https://drive.google.com/file/d/1qO0ED8AiXN6V0Y7KksI...

Zen status line
https://drive.google.com/file/d/1d9qQjqKhVRKSfh6fjkk...

Edited by francisuk25 (Thu 11-Jun-20 18:06:09)

Can't see where it shows the latency has doubled but it does look like your profile has been reset, give it a few days to settle I would advise.

G.INP is not yet enabled on your line. A change of ISP causes a reset of DLM and G.INP.

This is also why your download speed is slower. When G.INP is enabled in a couple of days, latency will reduce and speed increase.

The change is a software change in the fibre cab which directs traffic from the port (which provides your internet) over a different routing to the new ISP at the handover exchange.

Edited by sidef (Thu 11-Jun-20 18:38:00)

+1
It also turns on Interleaving, which is what is giving the 8ms latency addition, (most modems call it delay), to the underlying one on the connection. That too will go when G.INP is reactivated.

The OP needs to avoid re-sync'ing in the vain hope of improving things. It would more probably prevent G.INP kicking in as quick as it might otherwise.

Edited by RobertoS (Thu 11-Jun-20 18:42:08)

As everyone says, the 8ms latency figure in the Zen screenshot will (hopefully) change to Fast and remove that 8ms.

But I also wanted to point out that Zen has two POPs, Manchester and London. I have noticed that when I am connected through Manchester, the latency is 8ms higher than when I am connected though London.

Thanks for all the replies but i wasnt to sure if openreach would of kept the line info before the switch over to Zen.

Yeap, about half 1 this morning the FRITZ!Box DSL synced the connetion to 60114/17402 with G.INP downstream enabled, Finger cross it will resync back to the 70000 range within the next few days as im in the "10 day trainning period"

Signal-to-noise ratio dB is stil set to 6db/6db but before the switch from TalkTalk it was at 3db/6db

Edited by francisuk25 (Fri 12-Jun-20 20:52:45)

There is no ten-day training period. It is entirely a BT Wholesale construction and was always a myth anyway. Simply lousy initial wording by a non-techie "technical author" who screwed up.

Bear in mind this page is ten years old but is still correct. Also long before Openreach was created as a separate group company, and FTTC didn't exist.

The DLM on FTTC is totally different from the BT Wholesale one, which was applicable only to BT Wholesale-using ISPs. The Openreach FTTC/VDSL2 DLM is a different product entirely. (Though depending on which backhaul Zen have placed you a BT Wholesale IP Profile may also be applied).

Things get a bit more complex these days, so I need to update that whole site and these aspects in particular. But it is the Openreach DLM that is involved, Basically on a migration that DLM resets to defaults which is what you will be on, but it remembers the line history. IIRC it is 48-72 hours before your G.INP is re-enabled and the dropping of the SNRM either happens or starts dropping by 1dB every couple of days or so .

Edited by RobertoS (Sat 13-Jun-20 00:24:38)

I thought migration doesn't involved DLM resets to defaults if the product are FTTC 80/20 to FTTC 80/20 or FTTC 40/10 to FTTC 40/10. DLM will resets to defaults if the product are changing to 80/20 from 40/10 or from 80/20 to 40/10 as a migration switch (not for regrade orders on the same ISP). But, I have no experience on that because I never migration as I still with PN since 2010. Yes, ten years with PN.

Edited by adslmax (Sat 13-Jun-20 10:00:48)

In reply to a post by sidef:

G.INP is not yet enabled on your line. A change of ISP causes a reset of DLM and G.INP.

Handy to know, thanks.

In my other property I've just enabled a Zen connection (only on the upto 40mb service - it was with EE for previous owner). It was enabled a few days ago, but I've only been able to install the router today.


Receive Direction Send Direction
Max. DSLAM throughput kbit/s 40000 10000
Min. DSLAM throughput kbit/s 128 128
Attainable throughput kbit/s 29315 8700
Current throughput kbit/s 29315 8700
Seamless rate adaptation off off

Latency fast fast
Impulse Noise Protection (INP) 0 0
G.INP off off

Signal-to-noise ratio dB 6 6
Bitswap on on
Line attenuation dB 24 25
approximate line length m 470

Profile 17a
G.Vector off off

Carrier record A43 A43

Edited by kebabselector (Sat 13-Jun-20 15:21:54)