Zen G.Fast IP Profile?

Had G.Fast 160/30 from Zen installed yesterday.
BT Engineer line test showed it could do 404Mbit, I'm about 80m from the cabinet.

The problem is, I can only get about 140mbit download speeds. I've checked Zen portal line stats and BT wholesale checker and it shows my sync speed at 151866Kbps, with a download profile of 147000Kbps.

With g.fast, you cant get sync stats from the modem

I'm sure I've been profiled down because we reset the modem many times during the install as there's no instructions for setting it all up.

I phoned Zen to ask for my IP profile to be bumped to 160000 and was told there was no such thing on G.Fast. No amount of asking got me anywhere. He insisted it was synced at 160000Kbps and that it was just "bandwidth" problems. At lunchtime on a weekday.

So, am I wrong? Have I not been profiled down to 147 because of the amount of disconnects from the router? Or are Zen just being useless?

This could be the same as the effect seen on VDSL2 with G.INP activated, where the ISP's radius server receives a sync speed notification lower than the sync reported by the modem.

That lower sync speed is also what is used by BT Wholesale to set the IP Profile.

Bandwidth problems sounds like a novice first-line support response, talking rubbish.

Just my thoughts.

Give it a couple of days? Recently had an ADSL to FTTC upgrade where the download speed was lower than the handback. After a few days it bumped itself up.

I got through to another guy on chat who was great and willing to try and look up everything he could, then we talked it through on the phone.

The info Zen are getting from BT shows im synced at 160,000 and have a profile at the same level, but I'm still only getting 140mbit download speeds.

Nobody can explain why the zen portal, and the BT wholesale checker, are both showing a profile of 147,000.

Theres been another sync speed showing on my zen portal, so this data seems to be live and updating.

Zen Portal Image

I�m not fully sure what the issue is you are seeing, but if it is that your line profile is below your sync speed this is normal. I think BT used to apply a profile that was 88% of your sync speed. Looks like this has been revised up to 96%.

This is not something your isp can change.

My issue is that I'm being told by Zen over the phone that I'm syncing at 160mbit, but their own portal and BT wholesale checker, is showing the lower number and I'm only getting around 140mbit on speed tests.

I understand that my profile would be 96% of my sync, and if it was 96% of 160mbit I'd be completely happy.

As an Openreach engineer tested my line under a week ago saying it can easily sync at 400+mbit, I'm lost as to why it's not easily syncing at 160. Zen tell me it is, my speedtests tell me it isn't.

It's frustrating that there is no way to get sync speed directly from my modem.

Basically, with what seems to be a really good line to the cabinet, I expect to get 160

Your Zen Portal image two posts ago clearly says what your sync speed is. The difference between the two from 21 Oct to 23 Oct suggests DLM is reducing the sync for some reason.

Somebody you are speaking to is contradicting what your portal says. I would trust the portal.

You could try asking what figure the radius server is getting from BT Wholesale.

In reply to a post by Geordish:

I�m not fully sure what the issue is you are seeing, but if it is that your line profile is below your sync speed this is normal. I think BT used to apply a profile that was 88% of your sync speed. Looks like this has been revised up to 96%.

This is not something your isp can change.

88% is on ADSL2+. Standard on FTTC/VDSL2 is around 96%. With G.INP it is lower, more like 94% or so IIRC. G.Fast is not the same protocol as either but I don't know what it should be.

U could upgraded to 330/50 instead for an extra £10 a month. But I think Zen are free of charge to regrade for G.fast Modify order from 160/30 to 330/50 within 24 hour.

Openreach stated 160/30 are up to 145/30 and 330/50 are up to 300/50 because the max ip profile for 160/30 are 145600kbps and 30000kbps and 330/50 are 300300kbps and 50000kbps

Edited by adslmax (Mon 11-Nov-19 11:12:16)

In reply to a post by RobertoS:

This could be the same as the effect seen on VDSL2 with G.INP activated, where the ISP's radius server receives a sync speed notification lower than the sync reported by the modem.

That lower sync speed is also what is used by BT Wholesale to set the IP Profile.

Bandwidth problems sounds like a novice first-line support response, talking rubbish.

Just my thoughts.

Having that exact issue myself since DLM changed the Target Noise margin and increased the Level of G.inp, My sync is the max rate 79999kbps , Zen are reading the downstream speed as the sync rate on the GEA FTTC Service test 76.6mpbs but in the portal the IP profile is 70.39mbps actual throughput is 68mbps , That is 88% of the sync rate, it should be higher, the sync rate zen have is 72.72mbps in the portal The claim that bt have re configured the cvlan to 80mbps , not sure that is where the issue will lie, more like the BT BRAS server IMO

Did you get any further with this? I have a similar problem I think. I'm on the 330 package. Openreach engineer said line could support much higher (can't remember exactly what but maybe 4/500mbps). Sync is 330 - I was using a router with inbuilt g.fast modem so could verify that (although back on the open reach modem now). IP Profile is set to 303 on Openreach speed test page. I can't see a good reason why it can't be much closer to 330.

Zen support didn't really make much sense when I mentioned I was getting about 290mbps with an IP Profile of 303mbps:

"The maximum speed the line is capable of is 330Mbps but it's estimated it should get around 308Mbps, meaning the line is performing as we'd expect. When running tests you are getting the throughput speed which is a portion of 308Mbps available. To get the most accurate speeds I'd advise trying a direct PPPoE connection to the G.Fast Modem."

DSL Checker website gives a high and low of 330 for both clean and impacted. Not sure where Zen support get 308 from.

I got hold of a BT Smart Hub X which is for their G.Fast service and that shows a sync speed of 160/30 which is exactly what I'd expect. The Zen portal and Openreach checker show I'm still profiled at around 146 and nobody can give me a reason why.
The Zen portal shows slightly changing rates whenever my modem has been disconnected, so where this data is coming from nobody knows.

Since the handback threshold on my line is 95Mbit, Zen won't hand it back to BT and so they say there's nothing more I can do about it.

I've been told my cabinet is not contended, I can do 160mbit to the cabinet, but after that I get the same response you did, that I can't expect to get the the full 160 and the line is performing as Zen expect.

In reply to a post by adslmax:

U could upgraded to 330/50 instead for an extra £10 a month. But I think Zen are free of charge to regrade for G.fast Modify order from 160/30 to 330/50 within 24 hour.

Openreach stated 160/30 are up to 145/30 and 330/50 are up to 300/50 because the max ip profile for 160/30 are 145600kbps and 30000kbps and 330/50 are 300300kbps and 50000kbps

That would tie in with my experience, but have you got a link to where that�s stated, Max?

Yes, this also ties in with my speeds (not quite but very close) so would be very interested to read a bit more on this.

From the BT Wholesale speed test: "IP Profile for your line is: 303.91Mbps".

In reply to a post by gc8839:

Yes, this also ties in with my speeds (not quite but very close) so would be very interested to read a bit more on this.

From the BT Wholesale speed test: "IP Profile for your line is: 303.91Mbps".

Mine just gave 303.95, so as near the same as makes no difference.

Edited by stephengw (Wed 13-Nov-19 19:26:31)

In reply to a post by stephengw:

In reply to a post by adslmax:

U could upgraded to 330/50 instead for an extra £10 a month. But I think Zen are free of charge to regrade for G.fast Modify order from 160/30 to 330/50 within 24 hour.

Openreach stated 160/30 are up to 145/30 and 330/50 are up to 300/50 because the max ip profile for 160/30 are 145600kbps and 30000kbps and 330/50 are 300300kbps and 50000kbps

That would tie in with my experience, but have you got a link to where that�s stated, Max?

I'd also like to see where this is stated, as at no point in my purchase was I told that my "160" order would only ever be capable of 145.

I know everything is sold as "up to", but if you can't ever achieve 160, then it can't be "up to 160"? That's a bit of a swindle, isn't it?

G.fast 160/30 product will never sold you for 160Meg because of overhead and ip profile set by BTw and your ISP at 145Meg and it still up to 145 for true download speed with the sync rate of 159999Kbps (remember it will still 'up to') and depend on your line quality and line length from the G.fast pcp cabinet to your socket.

My gfast service go live today between 8am and 1pm with gfast 160/30. I will let you know what does BTw IP Profile rate are and the real throughput speed.

When I had my Zen G.fast installed this time last year the sync speed was 151836. A few weeks later it bumped up tp 159309 where it has stayed rock solid since. I can pretty much lean out of my window and touch the cabinet.
I believe you will just resync upwards

No need, I bumped to 330 a long time ago and it's been synced at just over 300mbit ever since.

Still annoys me they are allowed to sell you an "up to" speed which you will never ever be able to reach, but such is life.

Tbh this thread could be closed if I knew how.

That's good as you are much closer to the cabinet.

My throughput speed are 151/29 on ethernet (I hate up to speed) The engineer agree with me if my line max was 210 why not go for 210 instead of 160. He say it down to openreach product 160/30 and 330/50 and you get less on overheads and ip profile on both.

Nothing special about this on G.Fast. It has always been the case on all Openreach xDSL products. Even non-BT Wholesale, though they are the one with the widely known-about IP Profile.

What might be different is the advertised speed. On ADSLx and FTTC, as you know, they have to advertise "up to actual highest" for the product. Not "up to sync speed". They should be doing the same on G.Fast, I haven't checked.

FTTP is different. It always connects at the advertised speed. (Pedant mode - Or not at all). What happens about throughput I haven't looked into.

Would coming from FTTC to G.Fast would reset to a 10 day training period

Edited by francisuk25 (Sat 29-May-21 00:21:52)

In reply to a post by francisuk25:

Would coming from FTTC to G.Fast would reset to a 10 day training period

No, I thought that as well. But someone told me from kitz forum that FTTC and Gfast don't have 10 day training period. Only for ADSL/ADSL2/ADSL2+

Even on ADSLx the 10-day training was a myth promulgated by BT Wholesale. Their DLM always trained from Day 1, and the tenth day was merely the point at which they set in stone the lowest sync recorded in the period as the MSR. (Maximum Stable Rate).

From the MSR they set the FTR (Fault Threshold Rate). 70% or 80% of MSR, I think it started as one then changed to the other.

If you subsequently had a sync above the FTR they would not generally accept fault reports about low sync.

BTW still maintains this myth on FTTC . ISPs using their circuits have no option but to parrot it. On LLU and non BT Wholesale FTTC it can't exist, precisely because they don't use BTW. The relevant DLM on LLU is whatever the ISP may or may not provide, and on FTTC it is Openreach.