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Casa DS8x96 SC-QAM and OFDM configuration limits

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imix84
Casa DS8x96 SC-QAM and OFDM configuration limits

Dear community,
I am considering a CMTS upgrade, specifically looking to move to a Casa C40G. Based on the datasheets, I haven't been able to fully understand the configurability of the DS8x96 downstream card.Here is what I would like to achieve: 16 unique SC-QAM channels on each of the 8 ports, plus a shared OFDM block that is split across all 8 ports. Alternatively, sharing two OFDM blocks across 4 ports each would also work for me.Is the DS8x96 card capable of this specific configuration?Any insights or configuration examples would be greatly appreciated. Thanks in advance!

kwesibrunee
It has been a long time, but

It has been a long time, but if I remember right OFDM is split into 2 groups with four ports each, each group can be up to 96 MHz. but using this card strands you on software release 7.2 at the most which is about 8 years old now. The shared-ofdm is very awkward to configure.

If you can I would highly recommend just using a 8x192 card, the cost differential should be pretty minimal but the capabilities are very different. 8x192 can do 48/64 SC-Qams + 2 OFDM 192 MHz per port. It is also compatible with newer 8.x releases (8.x is not compatible with DS 8x96, US 16x4 or SMM 2x10)

imix84
Thank You!

Thank you very much for both the information and the advice!

cmcaldas
real numbers

the 8x96 ofdm supports 256, 512 and 1024Qam (shared bandwidth, ports 0,1,2,3 =1/0 and 4,5,6,7 =1/1)
C100G_2# show docsis down chan ut
Downstream Total-BW Utilization Reserved-BW Online Secondary Channel
Channel (Mb/Sec) Percentage Utilization Modems Modems Description
-------------------------------------------------------------------------------------------
1/0w (423M-519M Hz) 866.0 33 0 0 482 shared-ofdm
1/1w (423M-519M Hz) 866.0 10 0 0 130 shared-ofdm

the 8x192 supports 2 ofdm per port 256, 512, 1024, 2048 and 4096Qam
2/2/0w (471M-660M Hz) 2123.3 5 0 0 24 ofdm
2/2/1w (666M-855M Hz) 2123.3 3 0 0 24 ofdm

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