8900X R3 - VPN Passthrough not working

Discussions for BiPAC 8900 series: 8900AX-1600, 8900AX-2400, 8900X
billion_fan
Posts: 5272
Joined: Tue Jul 19, 2011 4:30 pm

Re: 8900X R3 - VPN Passthrough not working

Post by billion_fan » Mon May 18, 2020 3:11 pm

steveb wrote:
Mon May 18, 2020 2:43 pm
Hi - its been a month and the DSLAM is not giving me a better SNR and the line is as stable as it gets. I was wondering if there is something obvious in my config I have
Modulation just VDSL2 ticked
Profile just 17a ticked
US0 Enable
Phone line pair Inner pair
Capability Bitswap SRA both ticked and I have tried neither ticked and either ticked
PhyR Downstream ticked

The status info gives me
xDSL
Mode VDSL2
Traffic Type PTM
Status Up
Link Power State L0
Downstream Upstream
Line Coding (Trellis) On On
SNR Margin (dB) 6.3 5.6
Attenuation (dB) 18.3 0.0
Output Power (dBm) 13.0 7.6
Attainable Rate (Kbps) 71524 20935
Rate (Kbps) 70347 20000
B (# of bytes in Mux Data Frame) 243 239
M (# of Mux Data Frames in an RS codeword) 1 1
T (# of Mux Data Frames in an OH sub-frame) 0 64
R (# of redundancy bytes in the RS codeword) 10 0
S (# of data symbols over which the RS code word spans) 0.1104 0.3819
L (# of bits transmitted in each data symbol) 18398 5028
D (interleaver depth) 8 1
I (interleaver block size in bytes) 254 120
N (RS codeword size) 254 240
Delay (msec) 0 0
INP (DMT symbol) 48.00 0.00
OH Frames 0 0
OH Frame Errors 869 14058
RS Words 2171544664 77560259
RS Correctable Errors 87812 0
RS Uncorrectable Errors 0 0
HEC Errors 0 0
OCD Errors 0 0
LCD Errors 0 0
Total Cells 627064075 0
Data Cells 2356384400 0
Bit Errors 0 0
Total ES 24 6440
Total SES 15 22
Total UAS 406 391

On the ASUS DSL-AC68U I would have been getting around 75000 Kbps and an interleave depth of 1 (Fastpath) combined wwith an SNR of around 2.9 and a line attenuation of 11.8

Any ideas ?
All help appreciated cheers
Unfortunately on the Billion you can't tweak the SNR on a VDSL connection, to lower the SNR and increase downstream sync rate, everything else looks fine though (I have seen others Billion users with a SNR of 3, which is normally done by DLM on it own)

steveb
Posts: 8
Joined: Thu Apr 16, 2020 10:49 am

Re: 8900X R3 - VPN Passthrough not working

Post by steveb » Mon May 18, 2020 3:45 pm

Hi Billion fan - thank you for the response. I was wondering that the reason for this is the line attenuation being so high in comparison to the ASUS. I might have this wrong but normally line attenuation gives an indication of the distance from the cabinet - by working out the line noise? Given I am the same distance from the cabinet could it be possible that this modem is generating its own interference (bad connection/solder somewhere) and this is the reason why the DSLAM is not offering SNR = 3dB ?

Or am I mis-understanding the line attenuation on this unit ?

btw: The DSLAM is Broadcom - the main reason I chose this modem (the second being it having a gigabit port)

billion_fan
Posts: 5272
Joined: Tue Jul 19, 2011 4:30 pm

Re: 8900X R3 - VPN Passthrough not working

Post by billion_fan » Tue May 19, 2020 8:56 am

steveb wrote:
Mon May 18, 2020 3:45 pm
Hi Billion fan - thank you for the response. I was wondering that the reason for this is the line attenuation being so high in comparison to the ASUS. I might have this wrong but normally line attenuation gives an indication of the distance from the cabinet - by working out the line noise? Given I am the same distance from the cabinet could it be possible that this modem is generating its own interference (bad connection/solder somewhere) and this is the reason why the DSLAM is not offering SNR = 3dB ?

Or am I mis-understanding the line attenuation on this unit ?

btw: The DSLAM is Broadcom - the main reason I chose this modem (the second being it having a gigabit port)
If there a dodgy joint or connection, I would expect sync issues/drops etc. (as the device is brand new i would doubt it)

I think the line attenuation is down to the chipset/DMT code used in the router, and how it calculates the distance (broadcom code)

Normally I have found its down t0 DLM if 3db can used on your line, (as DLM normally automatically adjusts to errors/drops etc and adjusts the SNR/speeds accordingly)

steveb
Posts: 8
Joined: Thu Apr 16, 2020 10:49 am

Re: 8900X R3 - VPN Passthrough not working

Post by steveb » Thu Jun 18, 2020 7:44 am

Hi Billion_fan - still no joy, so I lost patience and got an Archer VR900 from ebay. Pretty much instantly 5% quicker and the SNR is going down as one would expect .. Bit of a shame so I'm going to have to take a hit on the 8900X and put it on ebay.

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