ubr7246VXR with use 8 downstream full only 150 Mb/s | docsis.org

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ubr7246VXR with use 8 downstream full only 150 Mb/s

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ubr7246VXR with use 8 downstream full only 150 Mb/s

help, use 8 channels downstream, but my maximum consumption only reflects 150mb / s.Mi ISP provides me 250 Mb / s, someone can explain what happens or how I can leverage my internet.

Can you publish your CMTS

Can you publish your CMTS running configuration (remove any passwords)


config file

File attachments: 
OK the most obvious way to

OK the most obvious way to increase your downstream throughput is

change this :
cable downstream modulation 64qam
to this :
cable downstream modulation 256qam

64QAM @ 6MHz width = about 26Mbps. 8 channels = 208Mbps total capacity.
256QAM @ 6MHz width = about 38Mbps. 8 channels = 304Mbps total capacity.

Assuming your plant is clean enough for 256 QAM downstream (usually not a problem).

thak you

I appreciate the attention given to solve the problems of others and not abuse it, but that all modem are connected to my CMTS DOCSIS 1.1 provisioned only when I have pure cable modem D3.0, I understand that the CMTS is D2.0 and D3.0 I will not say that, but at least if you have to stock up D2.0. What will be my problem?

There is the DOCSIS MAC

There is the DOCSIS MAC version, which will be 3.0, 2.0, 1.1, or 1.0

Separate to this, there is the QoS provisioned mode, which will be 1.1 or 1.0.
It is a common thing for people to see the 1.1 and think something is wrong.
But no, it is normal.

Try "show cable modem docsis version" to see both values for each modem.

DS in 256

Hi, i use 256QAM with uBR 7246 and work fine. I saw your running config and i can notice one thing. you are use the same frequency on all upstream port in all interfaces. Why?

upstream speeds

Just food for thought. downstream should be 256Qam and you can't go past 150Mb, but what's your upstream speed set at?
for 100Mb down, the lowest you can go is 4Mb. you need a min of 4 to get the 100 down. so 200Mb down, I set upstream at 18 to 20Mb for example.
have you posted your modem file? could be your max burst are too low. from the running config, looks like your only bonding on the downstream, not the upstream.


Upstream Speeds and QOS Profiles

Hi, I am new to the CMTS world and have had to create QOS Profiles to achieve desired Downstream Rates but I am stuck on 768Kbps for my Upstream. Could someone look at my config and please point me in the right direction? Thank you.

upstream speeds

now way will you ever reach 150Mb down with only 768Kb up.
the config shows a 64Qam on the upstream. at 3.2Mhz wide, it's around 13Mb Shared bandwidth..
Keep in mind with 64Qam upstream, your SNR has to be 28 and higher.
you need to post the SNR on the upstream and a copy of the modem file. I think the issue is with max burst setting in the modem. but an SNR of 18 will cause issues too, why we need to know what the upstream signal to noise is and what your modem file looks like.
rule of thumb.. 100Mb down needs a min of 4Mb up


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