dslreports logo
site
 
    All Forums Hot Topics Gallery
spc

spacer




how-to block ads


Search Topic:
uniqs
33927
share rss forum feed

IndyGamer

join:2012-09-26
reply to travelguy

Re: [Connectivity] New SB6120/6121 Firmware Released

Was going to get one of these modems today.

Should I get a zoom instead?

My old 5120 always been reliable but firmware never updated either as far as I know.

ExoticFish

join:2008-08-31
Stuarts Draft, VA
I'd go with the Zoom.


tshirt
Premium,MVM
join:2004-07-11
Snohomish, WA
kudos:5
Reviews:
·Comcast
reply to travelguy
I have a Moto6120 and I'm happy with it.
BUT based on the current Zoom "J" price, IF I was buying today, I'd seriously try to find one (I prefer local shopping whenever possible) nearby.
You can always rent for a few months to see what happens, or buy now a replace it next year, if something better shows up.

travelguy

join:1999-09-03
Santa Fe, NM
reply to ExoticFish
said by ExoticFish:

I'd go with the Zoom.

I would as well, if only because the Zoom is reported to have the ability to bond more uplink channels than the Motos do, if and when Comcast ever chooses to take advantage of that.

That said, it's not clear if the recent problem reports are due to the Moto firmware, changes on the CMTS side or some combination of things. There was a least one report that a Zoom buyer didn't see any change and ended returning the modem.

IndyGamer

join:2012-09-26
I seen the 8 channel vs 4 channels. Seems that would be more reliable if and when my neighbors leave uverse.

Thanks.


Wayne99021
Premium
join:2004-12-28
Mead, WA
kudos:1
Actually the Motorola SB 6140 is a 8 down 4 up modem just like the Zoom.
I have had that modem for about 6 weeks with no problems at all.


koitsu
Premium,MVM
join:2002-07-16
Mountain View, CA
kudos:23
reply to IndyGamer
The Zoom 5341J on Comcast (at least in my area) does bond to 8 downstream frequencies/channels. Comcast only offers 8 downstream frequencies (705/717/723/729/735/741/747/753MHz) in my area.

More bonded channels does not mean more reliability. I'm happy to refer you to an issue in my area which is affecting 747 and 753MHz caused by 4G/LTE cellular tower interference -- avoiding use of those frequencies is the only workaround at this time.

Now try to imagine what my experience would be like if I had a Zoom 5341J -- and here's evidence I've actually used one -- I'd be forced to use 747 and 753MHz, which would mean roughly 1/4 (technically 2/8) DOCSIS frames coming down the wire would result in the need for retransmission, which means delays + packet loss.

More bonded channels != more reliability. More bonded channels == more load distribution across multiple frequencies, vs. just banging on one single frequency, and eventually more bandwidth (not throughput/speed, but bandwidth). That's it. I feel sorry for anyone who uses the entire downstream spectrum in their area and has SNR issues on specific frequencies -- there's absolutely nothing the customer can do in the meantime but suffer.
--
Making life hard for others since 1977.
I speak for myself and not my employer/affiliates of my employer.


Wayne99021
Premium
join:2004-12-28
Mead, WA
kudos:1
reply to Wayne99021
Sorry, That should be 6141 not 6140.


Mike Wolf

join:2009-05-24
Beachwood, NJ
kudos:4

1 recommendation

reply to travelguy
Could have been an issue on Comcast's CMTS end that got messed up somehow and got straigtened out during a maintenance cycle. Phantom glitches.

catnapped

join:2010-11-22
Elizabethtown, PA
It is something of concern that there's a T4 that stays on top of the log and keeps changing its time on a refresh of the log page? Seems to update the time mark every 30 seconds. Don't remember if I was seeing that before 1.0.6.6 showed up.


koitsu
Premium,MVM
join:2002-07-16
Mountain View, CA
kudos:23
said by catnapped:

It is something of concern that there's a T4 that stays on top of the log and keeps changing its time on a refresh of the log page? Seems to update the time mark every 30 seconds. Don't remember if I was seeing that before 1.0.6.6 showed up.

Repeated issues of the exact same type/error simply update the timestamp of the top row log entry, rather than continually prepend additional rows.

What you describe indicates continual T4 timeouts, not occasional. Occasional T4 timeouts are acceptable. Constant, non-stop T4s are not. What you describe is indicative of a different problem and is not firmware related. Please start another thread or engage folks in the Comcast Direct forum for assistance; something at the head-end needs to be investigated.
--
Making life hard for others since 1977.
I speak for myself and not my employer/affiliates of my employer.

andyross
Premium,MVM
join:2003-05-04
Schaumburg, IL
reply to catnapped
said by catnapped:

It is something of concern that there's a T4 that stays on top of the log and keeps changing its time on a refresh of the log page? Seems to update the time mark every 30 seconds. Don't remember if I was seeing that before 1.0.6.6 showed up.

If you look at your signals, one of your upstream channels is probably listed as 'T4 Timeout'. That means it cannot connect on that one. Sometimes, rebooting will get it to connect. If you signals are marginal, it may occur again.


tshirt
Premium,MVM
join:2004-07-11
Snohomish, WA
kudos:5
reply to catnapped
T4's are often associated with upstream noise, so you could call in and ask what your upstream SNR is like.

andyross
Premium,MVM
join:2003-05-04
Schaumburg, IL
One of the interesting things is that, when people have posted issues on 3-channel upstream bonding with a T4'd channel, it's always the middle channel, even if it's not the middle frequency.


koitsu
Premium,MVM
join:2002-07-16
Mountain View, CA
kudos:23
said by andyross:

One of the interesting things is that, when people have posted issues on 3-channel upstream bonding with a T4'd channel, it's always the middle channel, even if it's not the middle frequency.

I cannot confirm this. Proof from my cable modem polling script logs, with firmware 1.0.6.6, are below.

Apologies for the syntax changes in the log too (I removed the modulation type sometime in late August to make things easier to read):

Sep 09 08:56:00   Up Channel  9:  23700000 Hz,  51 dBmV power, 5.120 Msym/sec, status: T4 TimeOut
Sep 09 08:58:00   Up Channel  9:  23700000 Hz,  51 dBmV power, 5.120 Msym/sec, status: T4 TimeOut
Aug 22 12:20:01   Up Channel  8:  30600000 Hz,  50 dBmV power, 5.120 Msym/sec, status: T4 TimeOut
Aug 22 12:20:01   Up Channel  9:  23700000 Hz,  50 dBmV power, 5.120 Msym/sec, status: T4 TimeOut
Aug 21 04:35:00   Up Channel  7:  35400000 Hz,  50 dBmV power, 2.560 Msym/sec, status: T4 TimeOut
Aug 21 04:35:00   Up Channel  9:  23700000 Hz,  49 dBmV power, 5.120 Msym/sec, status: T4 TimeOut
Aug 17 13:30:00    Up Channel  9:  23700000 Hz,  47 dBmV power, 5.120 Msym/sec, mods: [3] QPSK [3] 64QAM, status: T4 TimeOut
Aug 17 13:50:00    Up Channel  9:  23700000 Hz,  47 dBmV power, 5.120 Msym/sec, mods: [3] QPSK [3] 64QAM, status: T4 TimeOut
 

Let's pick August 17th as a test subject:

Aug 17 13:30:00        Firmware: SB_KOMODO-1.0.6.6-SCM00-NOSH (Apr 17 2012 15:09:37)
Aug 17 13:30:00    Boot Version: PSPU-Boot(25CLK) 1.0.12.
Aug 17 13:30:00     H/W Version: 5.0
Aug 17 13:30:00    Modem Uptime: 0 days 0h:2m:57s
Aug 17 13:30:00  Down Channel  3: 723000000 Hz,   1 dBmV power, 37 dB SNR, mods: QAM256
Aug 17 13:30:00  Down Channel  5: 735000000 Hz,   2 dBmV power, 36 dB SNR, mods: QAM256
Aug 17 13:30:00  Down Channel  7: 747000000 Hz,   1 dBmV power, 35 dB SNR, mods: QAM256
Aug 17 13:30:00  Down Channel  8: 753000000 Hz,   1 dBmV power, 35 dB SNR, mods: QAM256
Aug 17 13:30:00    Up Channel  8:  30600000 Hz,  47 dBmV power, 5.120 Msym/sec, mods: [3] QPSK [3] 64QAM, status: Success
Aug 17 13:30:00    Up Channel  7:  35400000 Hz,  48 dBmV power, 2.560 Msym/sec, mods: [3] QPSK [2] 16QAM, status: Success
Aug 17 13:30:00    Up Channel  9:  23700000 Hz,  47 dBmV power, 5.120 Msym/sec, mods: [3] QPSK [3] 64QAM, status: T4 TimeOut
Aug 17 13:30:00 Stats Channel  3: 5604427 unerrored, 44 correctable, 607 uncorrectable
Aug 17 13:30:00 Stats Channel  5: 5604430 unerrored, 11 correctable, 637 uncorrectable
Aug 17 13:30:00 Stats Channel  7: 5604344 unerrored, 13 correctable, 727 uncorrectable
Aug 17 13:30:00 Stats Channel  8: 5604424 unerrored, 21 correctable, 639 uncorrectable
 

The order you see these channels in is the order they're shown in the actual "Signal" web page interface (from left to right).

--
Making life hard for others since 1977.
I speak for myself and not my employer/affiliates of my employer.

n_w95482
Premium
join:2005-08-03
Ukiah, CA
reply to koitsu
I guess I've been lucky so far, my 6120 has been flawless with both 1.0.3.3 and 1.0.6.6. Hopefully 1.0.6.8 resolves the issues other people are having, I can imagine how frustrating it is .

said by koitsu:

More bonded channels does not mean more reliability. I'm happy to refer you to an issue in my area which is affecting 747 and 753MHz caused by 4G/LTE cellular tower interference -- avoiding use of those frequencies is the only workaround at this time.

Ah, very interesting discovery. I was tracking that thread earlier but hadn't read the last couple weeks of posts. That reminds me of an issue I had earlier this month while staying in Las Vegas for a week. My phone was on LTE most of the time (voice calls made it hand off to HSPA). Any time the phone was on LTE, it caused interference on certain TV channels (starting at 6 and roughly every 5-6 thereafter). Having the phone idle on the desk a few feet away caused occasional stuttering/tiling whenever it chirped at the tower, while doing a speedtest killed it completely. Even standing in the far corner of the bathroom (~18 ft, one wall) caused it to drop out.

The last night I was there, I ended up testing every single channel, writing down which ones were fine and which ones had issues, and reported it to the hotel service desk when I checked out. Hopefully they do something about it. I have no idea if the interference spread to adjacent rooms.

Verizon just turned on LTE service in my town, but our system here is on 549-597 MHz, so we should be spared of similar problems.
--
KI6RIT

catnapped

join:2010-11-22
Elizabethtown, PA
reply to andyross
said by andyross:

If you look at your signals, one of your upstream channels is probably listed as 'T4 Timeout'. That means it cannot connect on that one. Sometimes, rebooting will get it to connect. If you signals are marginal, it may occur again.

Yep...middle channel/middle (upload) frequency that had the T4. Rebooted and got rid of it, but we'll see how long it lasts....

catnapped

join:2010-11-22
Elizabethtown, PA
reply to travelguy
Guess that answers my question...T4 is back again on one of the upload channels (aaaargh). Levels on my end seem to be ok (at least from other posts I'd seen), so I wonder if there's something with the number that has to be read from their end that's telling.

travelguy

join:1999-09-03
Santa Fe, NM
Yes. The upstream power level you see is really an indirect look at what is going on. The key parameter for the upstream connection is the signal to noise ratio at the CMTS. The upstream power level you see on the modem signal page is the signal, but it's at the modem, not the CMTS, and you can't see any noise levels.


JeffRoss

@comcast.net
reply to ExoticFish
Of course, you would say that wouldn't you.


NetFixer
Freedom is NOT Free
Premium
join:2004-06-24
The Boro
Reviews:
·Cingular Wireless
·Comcast Business..
·Vonage

1 recommendation

reply to travelguy
said by travelguy:

If you are currently on 1033, I wouldn't do anything to try to get 1066. For that matter, Comcast may have suspended deployment of 1066, but I still wouldn't force a reboot.

Nope, firmware release SB_KOMODO-1.0.6.6-SCM00-NOSH has not been suspended. I activated a new SB6121 a couple of days after you made this post, and the first thing it did after connecting to the CMTS was to download that firmware release.

OTOH, I have not had any of the problems that others have reported with my SB6121 using the SB_KOMODO-1.0.6.6-SCM00-NOSH firmware (I have 4 channels downstream, 3 channels upstream, and I connect to an Arris/Cadant CMTS). That tells me that the problems being reported are not simply caused by the firmware per se, but may be a combination of the firmware and perhaps specific CMTS boxes/configuration and/or the hardware version of the modem itself (my hardware version is 5.0).
--
We can never have enough of nature.
We need to witness our own limits transgressed, and some life pasturing freely where we never wander.


Mike Wolf

join:2009-05-24
Beachwood, NJ
kudos:4
I use an SB6121 hardware version 5.0 and connect on a Arris/Cadant CMTS with 4 channels downstream and 3 channels upstream and haven't had any problems. I do hope that the latest firmware will improve speeds because I'm just seeeing 52Mbps down max.


telcodad
Premium
join:2011-09-16
Lincroft, NJ
kudos:15

1 edit
Same thing here (an SB6121, ver. 1.0.6.6 F/W, and connected to a Cadant/ARRIS CMTS with 4 channels downstream and 3 channels upstream) with no issues currently either.

My downstream carrier levels are usually around 0 dBmV (-3/+1) and my upstream levels are around +40 dBmV (-1/+2).

EDIT: My downstream SNRs are usually 36 or 37 dB (I've never called in to see what my upstream SNRs were).


Mike Wolf

join:2009-05-24
Beachwood, NJ
kudos:4
My downstream carrier levels are usually around 4 dBmv and my upstream levels are around 49 dBmv


pokesph
It Is Almost Fast
Premium
join:2001-06-25
Sacramento, CA
kudos:1
Reviews:
·Comcast
reply to travelguy
Just got a firmware update last night.. wait for it...

wait...

..its to firmware release SB_KOMODO-1.0.6.6-SCM00-NOSH
--
Webmaster - Steve
- - - - - - - - - - - -
»www.1-gb.net
»www.ppnstudio.com

travelguy

join:1999-09-03
Santa Fe, NM
said by pokesph:

Just got a firmware update last night.. wait for it... wait...
..its to firmware release SB_KOMODO-1.0.6.6-SCM00-NOSH

Well, fingers crossed you won't have any issues...


pokesph
It Is Almost Fast
Premium
join:2001-06-25
Sacramento, CA
kudos:1
Reviews:
·Comcast
said by travelguy:

Well, fingers crossed you won't have any issues...

Well now so far only issue has been the status page of the modem.. its not updating and shows as nothing synced and the modem as "offline"

No speed issues.. 35+ down, 5.5+ up (Blast tier) yet.
--
Webmaster - Steve
- - - - - - - - - - - -
»www.1-gb.net
»www.ppnstudio.com


koitsu
Premium,MVM
join:2002-07-16
Mountain View, CA
kudos:23
Try resetting the unit to factory defaults via the GUI, followed by doing a reboot through the GUI. It shouldn't have to download the firmware again, but the offline status and/or "broken" sync page may be fixed.

The offline status ordeal I know of (mentioned/discussed earlier in the thread), but the "broken" sync page I have never heard of until now. From what I can tell the offline status problem is fixed in 1.0.6.8 (I'm presently testing it out here).
--
Making life hard for others since 1977.
I speak for myself and not my employer/affiliates of my employer.

catnapped

join:2010-11-22
Elizabethtown, PA
reply to pokesph
said by pokesph:

Well now so far only issue has been the status page of the modem.. its not updating and shows as nothing synced and the modem as "offline"

Usually (at least in my case) there's a T4 somewhere if the status page shows offline/not completed. Other night was awful as the modem rebooted at least 5x overnight (2/3 upstream were T4'ed at one point that I saw). Not sure if it was maintenance or not as it hasn't returned since (knock wood).


koitsu
Premium,MVM
join:2002-07-16
Mountain View, CA
kudos:23
That issue (if it is an issue) may or may not have been fixed in 1.0.6.8. Explained here (in this same thread): »Re: [Connectivity] New SB6120/6121 Firmware Released

I saw this behaviour happen quite a few times with 1.0.6.6, but I haven't (so far) seen it happen with 1.0.6.8. I haven't done enough testing to state with complete certainty that it was a firmware issue however, but the 1.0.6.8 release notes do touch base somewhat on the topic.
--
Making life hard for others since 1977.
I speak for myself and not my employer/affiliates of my employer.