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Extreme 400 Tier: DOCSIS 3.0 or 3.1?

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Extreme 400 Tier: DOCSIS 3.0 or 3.1?

I have Netgear CM500 currently, which apparently doesn't support 400Mbps. (I was never told this by the agent when I was upgrading the plan.)

 

So I want to upgrade the modem, but I want to know:

 

1) if I buy a DOCSIS 3.1 modem like Netgear CM1000, will the physical layer of the service I get also DOCSIS 3.1? (OFDM, etc...)

2) or will it work as a backward compatible mode on DOCSIS 3.0 instead?

 

I know Xfinity 1Gbps is DOCSIS 3.1 only, but it seems like Xfinity 400Mbps (Extreme 400) also supports DOCSIS 3.0, so I want to clarify this.

Because if I buy a 3.1 modem but it works on 3.0 mode then I don't have to waste money on it.

Silver Problem Solver

Re: Extreme 400 Tier: DOCSIS 3.0 or 3.1?


@dreamdew wrote:

I have Netgear CM500 currently, which apparently doesn't support 400Mbps. (I was never told this by the agent when I was upgrading the plan.)

 

So I want to upgrade the modem, but I want to know:

 

1) if I buy a DOCSIS 3.1 modem like Netgear CM1000, will the physical layer of the service I get also DOCSIS 3.1? (OFDM, etc...)

2) or will it work as a backward compatible mode on DOCSIS 3.0 instead?

 

I know Xfinity 1Gbps is DOCSIS 3.1 only, but it seems like Xfinity 400Mbps (Extreme 400) also supports DOCSIS 3.0, so I want to clarify this.

Because if I buy a 3.1 modem but it works on 3.0 mode then I don't have to waste money on it.


I have the Arris XB6 which supports D3.1.  My plan is 400/10.  Any D3.1 will work with tiers that are lower than 1GB.  

 

If you purchase a D3.1 modem for your tier, you won't have to replace it when 1GB is available.

https://www.xfinity.com/gig#RolloutPlan

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Expert

Re: Extreme 400 Tier: DOCSIS 3.0 or 3.1?

@dreamdew wrote:

 

2) or will it work as a backward compatible mode on DOCSIS 3.0 instead?


Yes. It's backward compatible.



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Expert

Re: Extreme 400 Tier: DOCSIS 3.0 or 3.1?

@dreamdew

Go ahead and get the 3.1 modem. If it’s not provisioned for 1Gig but it’s a 3.1 modem it will use still use 3.1/the OFDM channel. 


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We ask that you post publicly so people with similar questions may benefit from the conversation.
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Silver Problem Solver

Re: Extreme 400 Tier: DOCSIS 3.0 or 3.1?

Looks like the OP kept his CM500, surprised they provisioned it, if not approved. It will be maxed out at that speed, any congestion will slow it down.

https://www.dslreports.com/forum/r32123089-