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Top Speed of Arris CM820a ?

Regular Contributor

Top Speed of Arris CM820a ?

Hi, I've had an Arris CM820a for years now, and it's been rock solid.

I'm thinking about upgrading it, but I'd first like to know what are the speed specs on this modem?

Here's the firmware, etc.

 

ARRIS DOCSIS 3.0 Touchstone WideBand Cable Modem
HW_REV: 1
VENDOR: Arris Interactive, L.L.C.
BOOTR: 1.2.1.52
SW_REV: 9.1.103M2AJ.CT
MODEL: CM820A

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Regular Contributor

Re: Top Speed of Arris CM820a ?


@anon86290 wrote:

Hi, I've had an Arris CM820a for years now, and it's been rock solid.

I'm thinking about upgrading it, but I'd first like to know what are the speed specs on this modem?

Here's the firmware, etc.

 

ARRIS DOCSIS 3.0 Touchstone WideBand Cable Modem
HW_REV: 1
VENDOR: Arris Interactive, L.L.C.
BOOTR: 1.2.1.52
SW_REV: 9.1.103M2AJ.CT
MODEL: CM820A


I think I found some info for it her:

https://mydeviceinfo.xfinity.com/device/arris-cm820a-425

285Mbps up

no down spec

 

But if you feel different, please respond.

Gold Problem Solver

Re: Top Speed of Arris CM820a ?


@anon86290 wrote: ... 285Mbps up no down spec ...

285 Mbps is the max rated download speed. The "up" is part of Comcast's "up to" caveat:

 


Actual plan speeds vary and are not guaranteed

Note that the spec reads "Wired Download Speed        Up to 285 Mbps".

Expert

Re: Top Speed of Arris CM820a ?

It's 285 down, not up. And FWIW, Comcast's rating is the only rating that truly matters.



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Regular Contributor

Re: Top Speed of Arris CM820a ?


@BruceW wrote:

@anon86290 wrote: ... 285Mbps up no down spec ...

285 Mbps is the max rated download speed. The "up" is part of Comcast's "up to" caveat:

 


Actual plan speeds vary and are not guaranteed

Note that the spec reads "Wired Download Speed        Up to 285 Mbps".


My mistake.  I know better than that.  Yes, 285 down.

Not sure why they specify 'wired', as I'm not aware that you could connect the moden to your pc via wierless.  I guess they just want to be sure that if the modem goes to a router first, and then wirelessly to your pc, all speeds are dependent on your router.

Regular Contributor

Re: Top Speed of Arris CM820a ?


@EG wrote:

It's 285 down, not up. And FWIW, Comcast's rating is the only rating that truly matters.


Any idea why there's no rating for upload speed?

 

Expert

Re: Top Speed of Arris CM820a ?

Because with cable systems it's so much slower compared to the downstream speed that it really doesn't matter anyway. Devices / ports download capabilities will always exceed the upload speed.



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I am a Customer Expert volunteering my time to help other customers here in the Forums.
We ask that you post publicly so people with similar questions may benefit from the conversation.
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Expert

Re: Top Speed of Arris CM820a ?


@anon86290 wrote:

Not sure why they specify 'wired', as I'm not aware that you could connect the moden to your pc via wierless.  I guess they just want to be sure that if the modem goes to a router first, and then wirelessly to your pc, all speeds are dependent on your router.


Because WiFi is subject to so many variables that only wired ethernet can be held to be accountable.



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I am a Customer Expert volunteering my time to help other customers here in the Forums.
We ask that you post publicly so people with similar questions may benefit from the conversation.
Was your question answered? Mark the post as Best Answer!
Gold Problem Solver

Re: Top Speed of Arris CM820a ?


@anon86290 wrote: ... Any idea why there's no rating for upload speed?

Also, most of their Internet plans are limited to 5 - 10 Mbps upstream. Even Gigabit is just 35. Comcast requires newly registered modems to be DOCSIS 3.0 or 3.1, and all such modems (AFAIK) are capable of upstream speeds around 100 Mbps or better. So, as stated, until and unless the technology changes dramatically, a modem upstream speed spec isn't needed.