Hi there,
we have a Arris Cadant C4 and Arris CM550A cable modems running docsis 2.0 standard
the problem is that we never get upload speeds over 1,8 mbit but download speed is very good 36Mbit.
test for 3,2Mhz-6,4Mhz channel-width and QPSK, QAM16, QAM64 modulation and lots of modem config but nothing result.
are not users it upstream. Upstream MER: 33dB, no errors.
I currently C4 config:
cable modulation-profile 5 iuc 1 mod qpsk pre-len 64 diff false fec-tbytes 0 fec-len 16 seed 338 burst-len 0 guard-time-size 8 last-cw false scrambler true docsis-mode atdma
cable modulation-profile 5 iuc 1 pre-type qpsk1 int-depth 1 int-blocksize 2048
cable modulation-profile 5 iuc 3 mod qpsk pre-len 640 diff false fec-tbytes 5 fec-len 34 seed 338 burst-len 0 guard-time-size 48 last-cw false scrambler true docsis-mode atdma
cable modulation-profile 5 iuc 3 pre-type qpsk1 int-depth 0 int-blocksize 2048
cable modulation-profile 5 iuc 4 mod qpsk pre-len 384 diff false fec-tbytes 5 fec-len 34 seed 338 burst-len 0 guard-time-size 48 last-cw false scrambler true docsis-mode atdma
cable modulation-profile 5 iuc 4 pre-type qpsk1 int-depth 0 int-blocksize 2048
cable modulation-profile 5 iuc 9 mod qam64 pre-len 104 diff false fec-tbytes 12 fec-len 81 seed 338 burst-len 11 guard-time-size 8 last-cw true scrambler true docsis-mode atdma
cable modulation-profile 5 iuc 9 pre-type qpsk1 int-depth 0 int-blocksize 2048
cable modulation-profile 5 iuc 10 mod qam64 pre-len 104 diff false fec-tbytes 16 fec-len 223 seed 338 burst-len 0 guard-time-size 8 last-cw true scrambler true docsis-mode atdma
cable modulation-profile 5 iuc 10 pre-type qpsk1 int-depth 0 int-blocksize 2048
cable modulation-profile 5 iuc 11 mod qam64 pre-len 104 diff false fec-tbytes 12 fec-len 81 seed 338 burst-len 0 guard-time-size 8 last-cw true scrambler true docsis-mode atdma
cable modulation-profile 5 iuc 11 pre-type qpsk1 int-depth 0 int-blocksize 2048
interface cable 3/0
cable downstream description "AN-3"
cable downstream frequency xy
cable downstream modulation 256qam
cable upstream 4 connector 4
cable upstream 4.0 modulation-profile 5
cable upstream 4.0 docsis-mode atdma
cable upstream 4.0 channel-width 6400000
cable upstream 4.0 frequency 27900000
cable upstream 4.0 power-level 10
cable upstream 4.0 no shutdown
cable upstream 4.1 description "QAM64_Teszt"
cable upstream 4.1 modulation-profile 5
cable upstream 4.1 docsis-mode atdma
cable upstream 4.1 channel-width 6400000
cable upstream 4.1 frequency 27900000
cable upstream 4.1 power-level 10
cable upstream 4.1 no shutdown
cable upstream 4 no shutdown
cable downstream no shutdown
no shutdown mac-port
and modem config:
Main
{
NetworkAccess 1;
DownstreamFrequency xy;
UpstreamChannelId xy;
UsServiceFlow
{
UsServiceFlowRef 1;
QosParamSetType 7;
TrafficPriority 1;
MaxRateSustained 10000000;
}
UsServiceFlow
{
UsServiceFlowRef 2;
QosParamSetType 7;
TrafficPriority 4;
MaxRateSustained 128000;
MaxConcatenatedBurst 4566;
MaxTrafficBurst 4566;
SchedulingType 2;
}
DsServiceFlow
{
DsServiceFlowRef 3;
QosParamSetType 7;
TrafficPriority 1;
MaxRateSustained 50000000;
}
DsServiceFlow
{
DsServiceFlowRef 4;
QosParamSetType 7;
TrafficPriority 4;
MaxRateSustained 128000;
}
VendorSpecific
{
.
.
.
.
}
any help would be great
kind regards
Peter