Hello I'm working for small company, We have around 3000 users. But we have problem with speed.
Our packet are
512/256
1024/256
1524/256
2048/256
But our costumers have problem with speed
Even if we set speed 1524/256, but the speed that they have is 512K to 700K. We have 5 CMTS arris 1500 and 6 nortel 1000.
Bigest problem is on one optical island.
55 TX
********
15 RX
********
39 SNR
********
On that Nortel 1000, we have on that CMTS 6 upstream channels. But speed is low 0.7MBps
Nortel 1000
USERS : 401
DOWNSTREAM: QAM 256 ( ONLY 1 DOWNSTREAM )
UPSTREAM : QPSK
UPSTREAM WIDTH : 3.3MHz
Users per UPSTREAM: 65
ROUTER PROCENT USAGE = 7%
LINK USAGE = 60 %
---------------------------------------------
DOWNLOAD / UPLOAD
[img]http://img535.imageshack.us/img535/5862/graphimg.png[/img]
----------------------------------------------------------------------
CONFIG OF MODEM
[img]http://img291.imageshack.us/img291/3259/trisata.jpg[/img]
[img]http://img94.imageshack.us/img94/1572/copyoftrisata.jpg[/img]
Idk what is problem. Did anyone have problem like this ? IS there any solution ?
Is the software for CMTS problem ?
Arris DOCSIS CMTS, Hardware rev. 14, Software rev. 3.3.335 (built 10/17/02 16:38:22 )
Also we are using SB5101E cable modem with software SB5101E-2.7.5.0-GA-00-NOSH.
Thanks
Faruk
Since it's Euro, what is the downstream modulation? upstream channel width and modulation? number of modems per upstream/downstream?
modem file, is there a max burst configured? firmware looks fine
~Carl
Nortel 1000
USERS : 401
DOWNSTREAM: QAM 256 ( ONLY 1 DOWNSTREAM )
UPSTREAM : QPSK
UPSTREAM WIDTH : 3.3MHz
Users per UPSTREAM: 65
Here is full cfg file
[URL=http://img291.imageshack.us/i/trisata.jpg/][IMG]http://img291.imageshack...
[URL=http://img94.imageshack.us/i/copyoftrisata.jpg/][IMG]http://img94.images...
Hi.
1)check upstream SNR
2)check upstream usage
3)check downstram usage
4)check router cpu usage,
5)check LAN/WAN links usage
John
HERE IS UPSTREAM / DOWNSTREAM USAGE
Green is downstream and red line is upstream. Maximum usage that we get on that CMTS is 15 MBPS download...
[URL=http://img689.imageshack.us/i/copyoftrisata.jpg/][IMG]http://img689.imag...
Link usage is 40 %
Ill have to chk CPU usage on router
check upstream snr - the chart looks as if something bad happened between 19-24. Similar charts can be seen after significant ingress noise is present in reverse path.
Chart shows that your upstream was maxed out at qpsk before it went bad. yes, downstream was high as well, but maxed upstream will result in slow downstream. if your snr is over 21, change your modulation to 16qam, you should be fine then. your cmts can't do 6.4 Mhz wide, so your only option is to go to 16qam speed wise. you should try going to a higher channel like 58Mhz, or what's clean enough to support 16qam
~Carl
no :( that chat had problem with link :) chat is usaly ok ill post new one
Oh OK.
I'm afraid Carl is right - change US modulation to 16QAM.
Is the speed low at all times ? or just at peak hours?
Are there errors on Ethernet interface of CMTS?
Ok we got solution, for now on QPSK ... It's very strange, i copied config from this nortel 1000 to other nortel 1000... And the other nortel 1000 is working fine. So it's probly the problem is in CMTS ...
here is DL/UL from old cmts and new. Speed is now ok on this CMTS.
OLD CMTS DAY BEFORE
[img]http://img651.imageshack.us/img651/1223/1804.jpg[/img]
OTHER CMTS NORETL 1000
[img]http://img94.imageshack.us/img94/4815/1904f.jpg[/img]
HERE IS INFO ABOUT CMTS
OLD
Arris DOCSIS CMTS, Hardware rev. 14, Software rev. 3.3.335 (built 10/17/02 16:38:22 )
NEW
Arris DOCSIS CMTS, Hardware rev. 11, Software rev. 3.7.305 (built 11/20/03 11:10:14 )
Can you please tell me is there any way to get newest software for nortel cmts 1000. Becose i think that software is problem...
And thx for advice next week we are switching modulation to 16QAM...
I edited my first post... now you can see all ... i posted wrog graf here is right graf ... IDK what is problem with this CMTS ....
+15 may be a bit strong for receive power levels. It's possible the modem may be getting overpowered and taking uncorrected FECs... ?
Also, what's the downstream channel utilization look like?
Downstream Signal Quality
IncludesContention Unerroreds Corrected Uncorrectables Microreflections
2 70338112 0 0 34
Upstream info :
Width ModProf SlotSize TXTimingOff RNGBckStart RNGBckEnd TXBckStart TXBckEnd
3.2 0 4 5847 2 5 3 10
We have problem with alot of users same have power level 6 or 0 so it's not power level problem
Speed is to lowest in peak time but it changes to much
example it says 0.7 now and 1 min later 0.4 then it foes 0.9 and so on ...
No ethernet errors...