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COjosh
join:2011-02-21

COjosh to 54761437

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Re: [DSL] Low upload speeds on VDSL

The CRC's could have come from the re-trains, that's normal, and the FEC's could also be leftovers as well...but 7k CRC's in 30mins IS bad, unless this log is right after a re-train.

Your upstream provisioned rate is WELL below 3Meg, that's why you aren't getting the correct upstream rate. Your up and down SNR seems a little low @ 10dB. Normally there is a difference between the two with the down SNR value usually being higher than the up....any idea what your loop length is?

I thought Frontier only offered 24/2 not 25/3, could be an area/equipment difference from the area I'm in.

It almost seems like there was a provisioning change that affected all the modem rates and SNR values. It could be outside trouble as well but without seeing what the max values are at the NID it's hard to tell.

Are you dry-loop or do you have POTS as well? If you have POTS- is your audio quality poor with static or humming in the background?

If you are dry- You can still plug a corded phone in at the NID and listen to the office battery. You can tell it's there by blowing into the phone and you will hear the wind back in your ear. Is it clear or do you hear something there with the mouthpiece covered?
54761437 (banned)
join:2013-01-18
Durham, NC

54761437 (banned)

Member

Thanks for the insight. I'm going to test at the NID (which I haven't done yet) and recheck modem stats. We have POTS, too, though. I'd like to go dry loop and use VoIP but with line problems like these, I don't know if that'd be advisable yet.

And yeah, I thought Frontier's provisioned rate for VDSL was 24/2, as well, but the general manager tells me it's being sold as 25/3 in our area. With tech like vectoring being available, shouldn't VDSL be able to support uploads higher than 2Mbit, given a relatively short loop length? Also, to answer your question on loop length, I'm not sure. I remember the field tech telling me it was around 2200 feet, I think.
54761437

54761437 (banned) to COjosh

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to COjosh
Okay, here are my line stats from outside at the NID. It looks like I'm somehow syncing slightly lower at the NID than in the house. In any event, I talked to the field tech manager again today and he said everything looks good at the CO but he's not sure what the point of failure is, and he'll try to get someone out this week to look at the NID and the box on the telephone pole.

(Note: these stats were taken after only being sync'd for like 2 minutes, so the error count is much lower)

VPI: N/A
VCI: N/A
VLAN: PTM 101
Broadband Mode Setting: MULTIMODE
Broadband Negotiated Mode: VDSL2 - 8B
Connection Status: Showtime
Downstream Speed: 25553 Kbps
Upstream Speed: 1147 Kbps
Retrains: 0
Retrain Timer: 0 Days, 0H:2M:29S
ATM QoS class: N/A
PTM VLAN QoS: 0
Near End CRC Errors Interleave: 2
Near End CRC Errors Fastpath : N/A
Far End CRC Errors Interleave : 0
Far End CRC Errors Fastpath : N/A
30 Minute Near End CRC Interleave : 2
30 Minute Near End CRC Fastpath : N/A
30 Minute Far End CRC Interleave : 0
30 Minute Far End CRC Fastpath : N/A
Near End RS FEC Interleave : 0
Near End RS FEC Fastpath : N/A
Far End RS FEC Interleave : 0
Far End RS FEC Fastpath : N/A
30 Minute Near End FEC Interleave : 203
30 Minute Near End FEC Fastpath : N/A
30 Minute Far End FEC Interleave : 0
30 Minute Far End FEC Fastpath : N/A
30 Minute Discarded Packets Downstream : 0
30 Minute Discarded Packets Upstream : 0
SNR Downstream : 10 dB
SNR Upstream : 10 dB
Attenuation Downstream : 0 dB
Attenuation Upstream : 0 dB
Power Downstream 18.5 dBm
Power Upstream 10.5 dBm
COjosh
join:2011-02-21

COjosh

Member

It's not abnormal to have slightly better sync #'s inside as opposed to the NID. If you have a decent home run to the modem, the better twist than the twist in the pair at the NID will improve sync rates some.

It looks like your modem doesn't report "Max Attainable" rates- The absolute maximum speed your line will sync at. The only way to see those #'s would be on a tech's meter or remote testing by Frontier.

Either way it would appear that your Upstream sync rate is STILL significantly lower than the 3Meg you should be getting.

What speed package are you paying for on your bill? Does it just say "VDSL" or "Broadband Max", or does it actually have the speed listed?

I'm still fairly confident it is a provisioning problem regardless of what the manager is telling you. In his mind "everything is ok at the CO" because you aren't losing sync and your downstream rate is where it is supposed to be.

I would push harder to have somebody look at your port provisioning.

At 2200ft your max upstream should be around 10Meg give or take a few Meg...and, by the way, Frontier doesn't use Vectoring with any of their DSL profiles to my knowledge...

-Josh
54761437 (banned)
join:2013-01-18
Durham, NC

54761437 (banned)

Member

Thanks again for the good info. I swear I was able to see max attainable before, but maybe Frontier pushed a firmware update and removed that from Broadband Stats.

The funny thing about both the website and the bill is it now says "Broadband Extreme" and mentions download speeds of "up to 24Mbps" but there's no mention of upload. However, according to every Frontier rep I've spoken to, including field techs, it's provisioned as 25/3, and Broadband Ultra is sold as 12/2. But a megabit discrepancy between downloads doesn't mean nearly as much to me as their refusal to be forthright about VDSL uploads on their website and in billing.

In any event, I'm still waiting on a tech to come out and I'll make sure to mention the provisioning issue if it hasn't been addressed by the MCO.

But would provisioning really solve the problem if I'm still seeing this many FEC and CRC errors?
Action2
join:2010-06-29
Champaign, IL

Action2

Member

That 24Mbps plan should be the bonded ADSL2+ version of plan. It is limited to 2Mb upload due to the nature of ADSL2+ lines. The VDSL version of extreme should be 25Mbps with an upload of higher than 2Mb/s if you are within the distance.
COjosh
join:2011-02-21

COjosh

Member

Action2- I agree, I originally thought that as wel,l but the modem stats clearly report VDSL 8b mode. It also doesn't have any stats listed for a Line 2 profile either.

Bungle- Provisioning wouldn't change your error problems considering that you "appear" to be UNDER provisioned. If you were OVER provisioned, say too fast for your distance, then you could see higher FEC and CRC rates.

As was stated before- FEC's/CRC's aren't really an issue unless the blocks are so large that they cause the modem to crash and re-train. That doesn't seem to be the issue here.

I would ask for the tech to tell you what your max rates, up and down as well as SNR values, are at the NID and have him contact the MCO to have the upstream corrected to reflect what is going on in real life.

It IS still possible that there is cable trouble causing your errors but that should have NO effect on the modem provisioning.

xDSL modems will run "best effort" algorithms to negotiate the maximum "safe" speed to run at. During the training process the modem "discusses" the current line condition w/ the DSLAM and decides upon the best possible stable speed for the loop condition- Your modem may "train-down" to a lower speed just to stay in sync, but it will NEVER train back up unless there is a forced reboot of the CPE. Being that you showed NO CHANGE in upstream rate after a forced reboot leads me to believe that the provisioning is just plain wrong.

The only case in where the modem would report a lower than advertised upstream profile would be if the DSL port is just set wrong....give or take some strange anomalies that do happen from time to time...
Action2
join:2010-06-29
Champaign, IL

Action2 to 54761437

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Taking another look, it really does seem that it is a profile issue. While you were only getting 1158 Kbps at first, it seems they dropped you down to 1147 Kbps after looking into the issue, maybe thinking you were over provisioned. It could be variance to the wiring, but hitting a sync rate that Frontier uses would be very hard to do.

1147 kbps is the standard ADSL2+ bonded upload rates Frontier is using in many areas.
54761437 (banned)
join:2013-01-18
Durham, NC

1 edit

54761437 (banned) to COjosh

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to COjosh
If and when the field tech actually calls or drops by, I'll be sure to get some specific values for max attainable rates and SNR. You mention that the modem may train down to attain sync, and that almost seems like what's been happening over the past few months. Like I said, I started off with an upload sync rate of about 1600Kbps, which has trended downward, almost logarithmically over time.

I should also mention after talking to several managers in other parts of NC, I've been given the impression 2Mbit is the max upload Frontier offers on ANY VDSL plan, which just sounds stupid and unrealistic to me. VDSL/2 can support higher uploads than ADSL2+, and given my distance I would think I'd easily be able to sync at 5Mbit.

Dealing with Frontier is like talking to a hydra where each head thinks something different.
COjosh
join:2011-02-21

COjosh

Member

Like I said, there is STILL the potential for some form of cable trouble knocking down your upstream rate. If you started off higher, and gradually- key word "GRADUALLY", your upstream rate has dropped off, that would indicate degradation in the OSP or elsewhere.

What modem are you on? An Actiontec or a Zyxel?

But if you abruptly went down then I would still say there is some provisioning snafu going on. Every once in a while DSLAM's will catch an update that screws up custom provisioning...yours may have been caught in that...

Your 1148 upstream rate is well below the necessary provisioning for a 2Meg upload. You would see an upstream rate around 2147 or so if it was set correctly for 2Meg.

I don't disagree that you "should" have higher than 2Meg upload, it's just a question if that is even available to you regardless of what the first manager said.

Frontier RARELY "tweaks" DSLAM line profiles outside of their normal provisioning and 24/2 IS the standard for VDSL in Frontierland. I have seen them make "exceptions" but they are rare at best.

24/1 is indeed weird...I'd like to see how this turns out...
plat2on1
join:2002-08-21
Hopewell Junction, NY

plat2on1

Member

frontier ultra or ultimate, whatever its called was advertised as 25/3 in this area when the website worked(it no longer works , doesn't list any plans and says online ordering not available in this service area) the other two plans were 6/1 and 12/2.
Action2
join:2010-06-29
Champaign, IL

Action2 to COjosh

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As far as I know 24/2 is the common provisioning for the ADSL2+ bonded version of Extreme while 25/3 is the VDSL version.

To me it still looks like he is being provisioned the wrong rate for the upload. 1147 is the rate that the 24/2 bonded plans use per line. In effect being provisioned the ADSL2+ speeds for VDSL.
54761437 (banned)
join:2013-01-18
Durham, NC

54761437 (banned) to COjosh

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I'm on the Actiontec V1000W. I think the Zyxels are mostly used for ADSL2 bonded service, if I'm not mistaken.

I'm still on the hook here, though, waiting for a call, but I'll certainly keep you and everyone here apprised of what's going on. And the field manager I'm dealing with here backs up Action2's post that the 2Mbit upload is what's provisioned on bonded ADSL, not VDSL. But if you go through any customer support channels, they refuse to acknowledge they offer higher than 2Mbit upload for anyone on any plan. Something isn't right about that, considering they used to advertise 3Mbit uploads on their Ultra plan.