Speed Boost, Modem Router reinstated

[#1]

After many months of running my Asus  DSL-AC86U as router only linked to a BTO ECI modem, I took the plunge yesterday (after a DSL-AC86U firmware upgrade) of reinstating its internal modem. The speed Down increased from 35.4Mbps to 37.2Mbps, and the speed UP from 11.7Mbps to 16.37Mbps (on Ookla and BTW Performance test).

That is significant. So far its been stable DLM has not intervened, and I now have access to some line stats on a better UI than I had originally. My PlusNet product limits me to 40Mbps Down, but a test yesterday shows 55Mbps possible. My Ac68U stats show connected at 49Mbps with a Max rate of 62Mbps Down Up is about 17Mbps connected and available of a maximum 20Mbps

I am still seeing a large number of CRC errors down (mainly at night). That worried me originally because DLM cut my speed with the AC68U and I assumed that CRC's were the culprit, but I'm beginning to think that they don't matter in this regard. Has anyone any thoughts on CRC's Down?

SNR is around 6.3Db Down, 6.8Db Up, which is reasonable, I hope. I feel as though walking on a frozen lake because originally, as I say, I was cut back by DLM quite severely, but I'm hoping that is all behind me. The stats now show connected to a Broadcom cabinet, they never did before.  Fingers Crossed!!

[#2]

Is this a DSL-AC86U or a DSL-AC68U ?

[#3]

Hi ray_dorset, it's an ASUS DSL-AC68U, sorry that I got the numbers fack to bront. As an aside, it's still performing at the faster speeds and DLM hasn't kicked in, all going smoothly, despite fingers crossed until they go stiff! Hopefully on a winner.

[#4]

Sounds like the ASUS DSL-AC68U now has G.INP enabled as it was disabled on your ECI modem.

Happy days

[#5]

As ray_dorset says you now have a G.INP compatible modem that is now using G.INP on your line where it wasn't before so rather than having interleaving which i suspect was enforce due to the errors you were getting with the ECI modem G.INP has taken over and allowed you to gain back what interleaving took away, nice to see 

[#6]

Not necessarily g.inp related.

Its not uncommon for some modems to gain higher sync speeds than others depending upon its chipset.

For example on my own line which is rock steady.
I get 3.5Mbps more using a HG612 over a Lantiq based modem (same VRX-268 chipset as the ECI modem).

The using a Zyxel VMG8324 I get another 3Mbps on top of that.  Most people using a BCM 63168 see a speed increase over a BCM 6368.

So same line and nearly 7Mbps difference between a VRX-268 based modem compared to one with a BCM63168.

This is why when beta testing a modem, I always put a HG612 on first to get a baseline figure to check performance against the one I'm testing.   The lantiq based chipset have always performed worse on my own line.
This is also why I repeatedly say you can not use speed as an indication to tell whether g.inp is in use.

[#7]

Kitz you may very well be right, although i was looking at it not from the speed gain but that the OP swapped from the Openreach ECI modem on a Huawei cab to the Asus which is Huawei based

As i understand it the Openreach ECI modem currently isn't G.INP compatible mine didn't work when G.INP was enabled on my line connected to a ECI cab and G.INP had to be removed as we have been seeing with pretty much all ECI lines now, I just assumed that the use of the Asus that the OP swapped to enabled G.INP but as you say it might just be the broadcom chipset being better on the line.

[#8]

If the OP is on a Huawei cab, yes you are entirely correct in saying that if he is using a BCM based modem, then he will most likely get a better sync speed than when using a Lantiq based chip modem.

Even most lines on ECI cabs seem to perform better with BCM based chipsets over the ECI modem..  although saying that there are a few who do better with the hacked ECI and opensource f/w.

The ECI modem is supposed to be G.INP compatible, but in the downstream direction only.   (See Question 3 - Openreach and G.INP).    Updated f/w for the ECI modems was rolled out late 2014/early 2015.

Re the current roll-back for ECI cabs..  I've not yet seen anyone with an ECI modem displaying the symptoms why Openreach are rolling back.   I have seen people with some older Fritz!boxes and Draytek modems displaying signs typical for the reason of roll-back. 

iirc the DSL-AC86U has a MediaTek chip. 

[#9]

Has anyone any thoughts on CRC's Down?

Individual CRCs dont count as far as DLM is concerned.   Errored Seconds and SES are the ones to watch out for.

You need to keep MTBE above 30 for DLM to class as 'OK' or above 300 to be classed as Green and for DLM to reverse any previous action it may have taken.

MTBE is too complicated to explain here - See DLM categorising the line