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RenaldoK
join:2005-07-02
Yukon, OK

1 edit

RenaldoK

Member

Signal levels acceptable (new SB 6182 MODEM)

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levels
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The uncorrectables seem rather high to me. I have the Ultimate Tier in Oklahoma City And was told I was provisioned for up to 150 Mbps ( even though OKC only has 100) thanks.

Edited title to reflect 6182 modem
Added screen shot of modem. Added all screen shots of levels.
m8trix
join:2003-12-24
Chandler, AZ

m8trix

Member

Re: Signal levels acceptable (new SB 6181 MODEM)

down stream is ok and as for the correctables that is hardly a blip, whats your upstream like

RenaldoK
join:2005-07-02
Yukon, OK

RenaldoK

Member

Click for full size
m8trix,

Cut the image off by accident... Thanks for your help.

Hard Harry7
join:2010-10-19
Narragansett, RI

Hard Harry7

Member

Signal levels look good. Don't worry too much about correctables, its the uncorrectables you have to watch for, and you don't have many. Any performance issues?

Also, sure you have a SB6181 and not a SB6141? If so, could you share some screenshots/photos?

RenaldoK
join:2005-07-02
Yukon, OK

RenaldoK

Member

Hard Harry,
It is actually a 6182. Added a screen shot and included all level screen shots in the first post.

Hard Harry7
join:2010-10-19
Narragansett, RI

Hard Harry7

Member

Man, I don't know where my head is at tonight. Im noobing it up. Think I might take a break. Thanks for the picture though.
Vitality9
Premium Member
join:2014-06-15

Vitality9

Premium Member

Would you happen to know the difference between the SB6180 and the SB6182? I have a SB6180 and am looking to get a new modem. I have a SB6182 reserved but I'm not sure if it's worth it.

RenaldoK
join:2005-07-02
Yukon, OK

RenaldoK

Member

I found this here.

»SB6182? New modem?

hope it helps.
moray
join:2013-10-16

moray to Hard Harry7

Member

to Hard Harry7
said by Hard Harry7:

its the uncorrectables you have to watch for

How can you know if it's a problem without seeing the "Total Unerrored Codewords", which my ancient SB6120 does report?

Hard Harry7
join:2010-10-19
Narragansett, RI

Hard Harry7

Member

said by moray:

How can you know if it's a problem without seeing the "Total Unerrored Codewords",

While its true that would make the calculation more accurate, you don't need to know the total to get a idea of connection health. If you reset/reboot the modem and you see 100+ uncorrectables in 10min, thats bad no matter what IMHO. Then again I thought the SB6182 was one of the newer 24channel modems, so take my comments with a grain of salt. ::le sigh::
moray
join:2013-10-16

moray

Member

said by Hard Harry7:

If you reset/reboot the modem and you see 100+ uncorrectables in 10min, thats bad no matter what IMHO.

Here's some real world data. My SB6120 uptime is 26 days. On one channel, the total uncorrectables is 490,358. There are 3,744 10-minute periods in 26 days, so my average uncorrectables per 10 minutes for that channel is 131. The other three channels have 2,285, 1,576, and 12,370 uncorrectables. OTOH, the total unerroreds for each channel is over 100,000,000,000. For the "bad" channel, the uncorrectable/unerrored ratio is thus about 5e-6, and for all of them taken together, about a quarter of that, so about one in a million. (The number of uncorrectables plus correctables is pretty negligible compared to the unerroreds, so I'm taking the number of unerroreds as the total just to make things simpler.)

I've never noticed any hiccup in performance, and without tracking these things day in and day out, or better still, hour in and hour out, or even less, I have no idea when they occur. For all I know, that one channel had a bad burst or two that I never noticed. I don't know what the threshold is for considering these values "bad", but it doesn't seem to be 100 uncorrectables in ten minutes if there were 20 million unerrored ones, which would be the average for my "bad" channel. Again, computing the average is pretty meaningless when you don't know the distribution of the errors. For all I know, most of the uncorrectables happened in that first 10 minutes.

So, I wouldn't worry about any of these numbers if observed performance is consistently what you're paying for. However, if you had uncorrectables hovering at a large percentage over a longish period of time, that could indicate a problem. Unfortunately, there would seem to be no way to determine this since it appears Motorola has eliminated the total unerrored count. I guess you could compare to the other channels, but for my example, one channel having a total uncorrectable 30x the others isn't a problem, I don't know what the threshold would be, and you'd have to track this regularly over small intervals to get an idea of the pattern of it.

Hard Harry7
join:2010-10-19
Narragansett, RI

Hard Harry7

Member

I think this thread has gotten off topic. I brought up the uncorrectables to emphasize the fact that correctables are just part of the TCP process. I wasn't trying to proof that uncorrectables = bad connection. YMMV