Best Practice Modulation Profiles

The following modulation profiles were taken from:

The suggestions are for ATDMA and TDMA-ATDMA mixed mode. The profile are ordered from good, average to bad upstream SNRs. We provide profiles for both Cisco and Casa syntax.

Best Practice Modulation Profiles (Cisco Syntax)

# ATDMA: good SNR
cable modulation-profile 221 request 0 16 0 22 16qam scrambler 152 no-diff 32 fixed qpsk1 1 2048
cable modulation-profile 221 initial 5 34 0 48 16qam scrambler 152 no-diff 384 fixed qpsk1 1 2048
cable modulation-profile 221 station 5 34 0 48 16qam scrambler 152 no-diff 384 fixed qpsk1 1 2048
cable modulation-profile 221 a-short 6 76 6 22 64qam scrambler 152 no-diff 64 shortened qpsk1 0 2048
cable modulation-profile 221 a-long 9 232 0 22 64qam scrambler 152 no-diff 64 shortened qpsk1 0 2048
cable modulation-profile 221 a-ugs 9 232 0 22 64qam scrambler 152 no-diff 64 shortened qpsk1 1 2048

# ATDMA: average SNR
cable modulation-profile 222 request 0 16 0 22 16qam scrambler 152 no-diff 32 fixed qpsk1 1 2048
cable modulation-profile 222 initial 5 34 0 48 16qam scrambler 152 no-diff 384 fixed qpsk1 1 2048
cable modulation-profile 222 station 5 34 0 48 16qam scrambler 152 no-diff 384 fixed qpsk1 1 2048
cable modulation-profile 222 a-short 4 76 7 22 16qam scrambler 152 no-diff 64 shortened qpsk1 0 2048
cable modulation-profile 222 a-long 9 232 0 22 16qam scrambler 152 no-diff 64 shortened qpsk1 0 2048
cable modulation-profile 222 a-ugs 9 232 0 22 16qam scrambler 152 no-diff 64 shortened qpsk1 1 2048

# ATDMA: bad SNR
cable modulation-profile 223 request 0 16 0 22 qpsk scrambler 152 no-diff 32 fixed qpsk0 1 2048
cable modulation-profile 223 initial 5 34 0 48 qpsk scrambler 152 no-diff 384 fixed qpsk0 1 2048
cable modulation-profile 223 station 5 34 0 48 qpsk scrambler 152 no-diff 384 fixed qpsk0 1 2048
cable modulation-profile 223 a-short 4 76 7 22 qpsk scrambler 152 no-diff 64 shortened qpsk0 0 2048
cable modulation-profile 223 a-long 9 232 0 22 qpsk scrambler 152 no-diff 64 shortened qpsk0 0 2048
cable modulation-profile 223 a-ugs 9 232 0 22 qpsk scrambler 152 no-diff 64 shortened qpsk0 1 2048


# TDMA-ATDMA: good SNR
cable modulation-profile 121 request 0 16 0 22 16qam scrambler 152 no-diff 36 fixed
cable modulation-profile 121 initial 5 34 0 48 16qam scrambler 152 no-diff 256 fixed
cable modulation-profile 121 station 5 34 0 48 16qam scrambler 152 no-diff 256 fixed
cable modulation-profile 121 short 3 76 12 22 16qam scrambler 152 no-diff 64 shortened
cable modulation-profile 121 long 9 232 0 22 16qam scrambler 152 no-diff 64 shortened
cable modulation-profile 121 a-short 6 76 6 22 64qam scrambler 152 no-diff 64 shortened qpsk0 1 2048
cable modulation-profile 121 a-long 9 232 0 22 64qam scrambler 152 no-diff 64 shortened qpsk0 1 2048
cable modulation-profile 121 a-ugs 9 232 0 22 64qam scrambler 152 no-diff 64 shortened qpsk1 1 2048

# TDMA-ATDMA: average SNR
cable modulation-profile 122 request 0 16 0 22 16qam scrambler 152 no-diff 36 fixed  
cable modulation-profile 122 initial 5 34 0 48 16qam scrambler 152 no-diff 256 fixed  
cable modulation-profile 122 station 5 34 0 48 16qam scrambler 152 no-diff 256 fixed  
cable modulation-profile 122 short 3 76 12 22 16qam scrambler 152 no-diff 64 shortened  
cable modulation-profile 122 long 9 232 0 22 16qam scrambler 152 no-diff 64 shortened  
cable modulation-profile 122 a-short 4 76 7 22 16qam scrambler 152 no-diff 64 shortened qpsk1 0 2048  
cable modulation-profile 122 a-long 9 232 0 22 16qam scrambler 152 no-diff 64 shortened qpsk1 0 2048  
cable modulation-profile 122 a-ugs 9 232 0 22 16qam scrambler 152 no-diff 64 shortened qpsk1 1 2048

# TDMA-ATDMA: bad SNR
cable modulation-profile 123 request 0 16 0 22 qpsk scrambler 152 no-diff 36 fixed  
cable modulation-profile 123 initial 5 34 0 48 qpsk scrambler 152 no-diff 256 fixed  
cable modulation-profile 123 station 5 34 0 48 qpsk scrambler 152 no-diff 256 fixed  
cable modulation-profile 123 short 3 76 12 22 qpsk scrambler 152 no-diff 64 shortened  
cable modulation-profile 123 long 9 232 0 22 qpsk scrambler 152 no-diff 64 shortened  
cable modulation-profile 123 a-short 3 76 12 22 qpsk scrambler 152 no-diff 64 shortened qpsk0 0 2048  
cable modulation-profile 123 a-long 9 232 0 22 qpsk scrambler 152 no-diff 64 shortened qpsk0 0 2048  
cable modulation-profile 123 a-ugs 9 232 0 22 qpsk scrambler 152 no-diff 64 shortened qpsk0 1 2048

Best Practice Modulation Profiles (Casa Syntax)

# ATDMA: good SNR
modulation-profile 6
 request atdma 16qam off 32 0 16 152 0 22 fixed on 1 2048 qpsk1
 initial atdma 16qam off 384 5 34 152 0 48 fixed on 1 2048 qpsk1
 station atdma 16qam off 384 5 34 152 0 48 fixed on 1 2048 qpsk1
 a-short atdma 64qam off 64 6 76 152 6 22 shortened on 0 2048 qpsk1
 a-long atdma 64qam off 64 9 232 152 0 22 shortened on 0 2048 qpsk1
 ugs atdma 64qam off 64 9 232 152 0 22 shortened on 1 2048 qpsk1

# ATDMA: average SNR
modulation-profile 7
 request atdma 16qam off 32 0 16 152 0 22 fixed on 1 2048 qpsk1
 initial atdma 16qam off 384 5 34 152 0 48 fixed on 1 2048 qpsk1
 station atdma 16qam off 384 5 34 152 0 48 fixed on 1 2048 qpsk1
 a-short atdma 16qam off 64 4 76 152 7 22 shortened on 0 2048 qpsk1
 a-long atdma 16qam off 64 9 232 152 0 22 shortened on 0 2048 qpsk1
 ugs atdma 16qam off 64 9 232 152 0 22 shortened on 1 2048 qpsk1

# ATDMA: bad SNR
modulation-profile 8
 request atdma qpsk off 32 0 16 152 0 22 fixed on 1 2048 qpsk0
 initial atdma qpsk off 384 5 34 152 0 48 fixed on 1 2048 qpsk0
 station atdma qpsk off 384 5 34 152 0 48 fixed on 1 2048 qpsk0
 a-short atdma qpsk off 64 4 76 152 7 22 shortened on 0 2048 qpsk0
 a-long atdma qpsk off 64 9 232 152 0 22 shortened on 0 2048 qpsk0
 ugs atdma qpsk off 64 9 232 152 0 22 shortened on 1 2048 qpsk0


# TDMA-ATDMA: good SNR
modulation-profile 9
 request tdma 16qam off 36 0 16 152 0 22 fixed on
 initial tdma 16qam off 256 5 34 152 0 48 fixed on
 station tdma 16qam off 256 5 34 152 0 48 fixed on
 short tdma 16qam off 64 3 76 152 12 22 shortened on
 long tdma 16qam off 64 9 232 152 0 22 shortened on
 a-short atdma 64qam off 64 6 76 152 6 22 shortened on 1 2048 qpsk0
 a-long atdma 64qam off 64 9 232 152 0 22 shortened on 1 2048 qpsk0
 ugs atdma 64qam off 64 9 232 152 0 22 shortened on 1 2048 qpsk1

# TDMA-ATDMA: average SNR
modulation-profile 10
 request tdma 16qam off 36 0 16 152 0 22 fixed on
 initial tdma 16qam off 256 5 34 152 0 48 fixed on
 station tdma 16qam off 256 5 34 152 0 48 fixed on
 short tdma 16qam off 64 3 76 152 12 22 shortened on
 long tdma 16qam off 64 9 232 152 0 22 shortened on
 a-short atdma 16qam off 64 4 76 152 7 22 shortened on 0 2048 qpsk1
 a-long atdma 16qam off 64 9 232 152 0 22 shortened on 0 2048 qpsk1
 ugs atdma 16qam off 64 9 232 152 0 22 shortened on 1 2048 qpsk1

# TDMA-ATDMA: bad SNR
modulation-profile 11
 request tdma qpsk off 36 0 16 152 0 22 fixed on
 initial tdma qpsk off 256 5 34 152 0 48 fixed on
 station tdma qpsk off 256 5 34 152 0 48 fixed on
 short tdma qpsk off 64 3 76 152 12 22 shortened on
 long tdma qpsk off 64 9 232 152 0 22 shortened on
 a-short atdma qpsk off 64 3 76 152 12 22 shortened on 0 2048 qpsk0
 a-long atdma qpsk off 64 9 232 152 0 22 shortened on 0 2048 qpsk0
 ugs atdma qpsk off 64 9 232 152 0 22 shortened on 1 2048 qpsk0

Assignment to Upstreams (Cisco Syntax)

cable upstream 0 threshold snr-profiles 28 16
# TDMA-ATDMA
cable upstream 0 modulation-profile 121 122 123
# ATDMA
cable upstream 0 modulation-profile 221 222 223

Assignment to Upstreams (Casa Syntax)

# TDMA-ATDMA
logical-channel 0 profile 9 secondary-profile 10,11
# ATDMA
logical-channel 0 profile 6 secondary-profile 7,8

Notes on live system change

This table contains an overview of CMTSs and if sth happens e.g. to the modems (online) when changing the modulation profile. In general all modems should stay online when changing the modulation profile on a live system.

CMTS	Interruption of online modems	Notes
Cisco ubr10k

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Notes on live system change

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Angel Kozew