Hi
Please help to configure a modulation-profile that allows to have more upload bandwidth considering the upstream signal-quality(USSNR) of the node connected to the Upstream port of the CMTS
which is the best configuration option to use to have a good operation
For example I have port 11/10 which has an average upstream signal-quality of 33 (I only use 4 channels, currently the nodes only support 40 Mhz)
CASA-C100G#show upstream signal-quality | include 11/10
11/10.0/0 35.1
11/10.0/1 0.0
11/10.1/0 34.4
11/10.1/1 0.0
11/10.2/0 33.4
11/10.2/1 0.0
11/10.3/0 32.4
Current configuration modulation-profile
modulation-profile 10
request atdma qpsk off 64 0 16 338 0 16 fixed on 1 1536 qpsk0
initial atdma qpsk off 640 5 34 338 0 48 fixed on 1 1536 qpsk0
station atdma qpsk off 384 5 34 338 0 48 fixed on 1 1536 qpsk0
a-short atdma qpsk off 104 12 75 338 6 16 shortened on 1 1536 qpsk1
a-long atdma qpsk off 104 16 220 338 0 16 shortened on 1 1536 qpsk1
modulation-profile 16
request atdma qpsk off 64 0 16 338 0 16 fixed on 1 1536 qpsk0
initial atdma qpsk off 640 5 34 338 0 48 fixed on 1 1536 qpsk0
station atdma qpsk off 384 5 34 338 0 48 fixed on 1 1536 qpsk0
a-short atdma 16qam off 104 12 75 338 6 16 shortened on 1 1536 qpsk1
a-long atdma 16qam off 104 16 220 338 0 16 shortened on 1 1536 qpsk1
modulation-profile 64
request atdma qpsk off 64 0 16 338 0 16 fixed on 1 1536 qpsk0
initial atdma qpsk off 640 5 34 338 0 48 fixed on 1 1536 qpsk0
station atdma qpsk off 384 5 34 338 0 48 fixed on 1 1536 qpsk0
a-short atdma 64qam off 104 12 75 338 6 16 shortened on 1 1536 qpsk1
a-long atdma 64qam off 104 16 220 338 0 16 shortened on 1 1536 qpsk1
This is the interface upstream configuration
CASA-C100G#show interface upstream 11/10 brief
interface upstream 11/10.0
description "El Firme"
spectrum-rule 1
frequency 40000000
channel-width 3200000
power-level 8
ingress-cancellation
logical-channel 0 description "El Firme"
logical-channel 0 profile 64
logical-channel 0 minislot 2
logical-channel 0 ranging-backoff 2 8
logical-channel 0 pre-equalization
no logical-channel 0 shutdown
logical-channel 1 profile 2
logical-channel 1 minislot 2
logical-channel 1 shutdown
no shutdown
interface upstream 11/10.1
description "El Firme"
spectrum-rule 1
frequency 36000000
channel-width 3200000
power-level 8
ingress-cancellation
logical-channel 0 description "El Firme"
logical-channel 0 profile 64
logical-channel 0 minislot 2
logical-channel 0 ranging-backoff 2 8
logical-channel 0 pre-equalization
no logical-channel 0 shutdown
logical-channel 1 profile 2
logical-channel 1 minislot 2
logical-channel 1 shutdown
no shutdown
interface upstream 11/10.2
description "El Firme"
spectrum-rule 1
frequency 32000000
channel-width 3200000
power-level 8
ingress-cancellation
logical-channel 0 description "El Firme"
logical-channel 0 profile 64
logical-channel 0 minislot 2
logical-channel 0 ranging-backoff 2 8
logical-channel 0 pre-equalization
no logical-channel 0 shutdown
logical-channel 1 profile 2
logical-channel 1 minislot 2
logical-channel 1 shutdown
no shutdown
interface upstream 11/10.3
description "El Firme"
spectrum-rule 1
frequency 28000000
channel-width 3200000
power-level 8
ingress-cancellation
logical-channel 0 description "El Firme"
logical-channel 0 profile 64 secondary-profile 16
logical-channel 0 minislot 2
logical-channel 0 ranging-backoff 2 8
logical-channel 0 pre-equalization
no logical-channel 0 shutdown
logical-channel 1 profile 2
logical-channel 1 minislot 2
logical-channel 1 shutdown
no shutdown
Considering the quality of the upstream signal, (Average of 33) I can change the channel width to 6.4MH and use QPSK, 16-QAM, 64-QAM
Please I await your help to increase the bandwidth per upload port, I have ports that have 100% Utilization for periods of time
what is the best recommended configuration
this configuration is on a CMTS C100 Casa Systems
I am attentive to the comments to have help
regards
I generally configure the lowest carrier at 3.2Mhz and the three higher carriers at 6.4Mhz. with spectrum management you can set it lower the modulation profile if it goes below a set snr.
Upstream Total-BW Utilization Online Secondary Channel
Slot/Port.Channel (Mb/Sec) Percentage Modems Modems Description
-----------------------------------------------------------------------------
11/0.0 (36320000 Hz) 30.7 14 49 63 Node-4
11/0.1 (29820000 Hz) 30.7 15 33 84 Node-4
11/0.2 (23420000 Hz) 30.7 14 14 97 Node-4
11/0.3 (18620000 Hz) 15.4 22 23 85 Node-4
post your email, can help with sample config
Hi, also you can take a look on this topic: https://docsis.org/comment/8126#comment-8126
Hi
For example a node that averages these SNR values as Interface upstream 10/6
CASA-C100G#show upstream signal-quality | include 10/6
10/6.0/0 32.8
10/6.0/1 0.0
10/6.1/0 32.6
10/6.1/1 0.0
10/6.2/0 31.7
10/6.2/1 0.0
10/6.3/0 31.9
Question:
I can use a channel-width of 6.4Mhz and not generate problems ?
Currently all my Upstream ports are configured with channel-width 3.2 Mhz, I want to expand to channel-width 6.4Mhz to offer more upload speed
I am attentive to more comments that can help me
I recommend 3 @ 6.4Mhz 64Qam and 1 @ 3.2Mhz 16Qam or qpsk if snr is below 21 for two reasons. 1st your lower carrier will be closer to the low end with noise and second you'll always have some modems at max transmit levels and should be able to stay online.
test it on a single node for a few days or when you feel comfortable to deploy it system wide. worse case, a few nodes at a time and monitor and the move onto next few set of nodes.