Unlimited Fibre 2 predicted speed accuracy?

I'm currently on Unlimited Fibre 1 and was wondering if there was a way to accurately predict Unlimited Fibre 2 speeds prior to requesting upgrading? Eg, entering my phone no and post code into Zen's site comes up with:-

Unlimited 1:-
40.0/10.0 (typical download speed)
36.0-40.0 (typical download range)

Unlimited 2:-
54.0/13.9 (typical download speed)
48.0-75.6 (typical download range)

...suggesting that I'd only get a +35% speed boost (40Mbps to 54Mbps typical download speed increase). However when logging into my Fritzbox 7530 router, the DSL stats information page states:-

Current Throughput : 39998 / 9999
Attainable throughput : 73859 / 20743

...which to me suggests that the router is likely able to get the max 74Mbps (+84% speed boost) and is currently capped at 40Mbps purely due to package choice? (Is that what that means)? When there's such a disparity between Zen's prediction vs router's "Attainable throughput" measurements, which in your experience is the more accurate prediction if upgrading?

Also, can you upgrade from Unlimited 1 Fibre (12-months) to Unlimited 2 Fibre (12-months) whilst still within the first 12 months contract, or do you have to wait until the 12 months has elapsed?

Thanks.

Would you rather Zen predict 75.6 Mbps and be upset when your maximum sync turns out to be 73.8 Mbps

OR

for them to take a more measured approach that means it seems likely you weill see well above the 48 Mbps minimum.

All based on your figures which you said "48.0-75.6 (typical download range)"

As for reality - only way to be 99.9% sure is to run the VDSL2 service at the 80/20 cap and see how it behaves over a timeframe of a few weeks.

Thanks for your reply. I think I'm more curious as to what the router statistic "Attainable throughput" actually means and if anyone here found it a reliable predictor going from Fibre 1 to 2. Is it the speed at which the Fritzbox has been proven to "talk" to the device in the cabinet but it's simply being artificially capped to 40mbps due to Fibre 1 package (which sounds extremely promising) or am I misreading that and does it mean something else?

Personally I don't think I'll bother upgrading from 40 to 54mbps, but 40 to +70mbps sounds a lot more enticing. I did want a rough guide though before requesting an upgrade as I'm still in the first 12 months contract of Fibre 1 and didn't want to mess Zen about going back & forth if I'm misreading what "Attainable throughput" actually means (as it's actually being measured by the router).

Edited by deleted (Fri 06-Dec-19 22:07:05)

I would predict 60-65 down 15 up going off the router

In reply to a post by TheButler:

I think I'm more curious as to what the router statistic "Attainable throughput" actually means and if anyone here found it a reliable predictor going from Fibre 1 to 2.

Attainable can be a bit of a misnomer. Several factors affect it, not least whether your line is interleaved or not (interleaving can inflate the attainable figure), whether you're on an ECI or Huawei street cabinet (Huawei can activate G.INP on the line, ECI not), etc. For example my interleaved line currently on an ECI cabinet, Zen Unlimited Fibre 2 has the following current stats:

Text
1 23	Downstream      Upstream Maximum Attainable Sync Rate:   71504 kbps      25664 kbpsActual Sync Rate:       63183 kbps      20000 kbps

As you can see the current sync is almost 10,000 kbps lower than the attainable figure.
I certainly wouldn't rely on the attainable figure at all for basing your decision on upgrading.

As has been said, the only real way to know, is to try it.

As you can see the current sync is almost 10,000 kbps lower than the attainable figure. I certainly wouldn't rely on the attainable figure at all for basing your decision on upgrading. As has been said, the only real way to know, is to try it.

^ OK that was the stuff I was looking for. Thanks very much for all your help.

Edited by deleted (Mon 09-Dec-19 13:22:39)