Receiving DOCSIS 3.1 Service?

[Topology]

Is there a way to determine whether a Netgear CM1200 modem (V1.02.02) is receiving DOCSIS 3.1 (rather than 3.0) service?

The cable connection information reported by the modem has remained unchanged, after successfully upgrading from 275 Mbps to 1000 Mbps service (Xfinity).  Specifically, the downstream bonded channels 1-32 are all locked (QAM256), the upstream bonded channels 1-4 are locked (ATDMA), downstream OFDM channel 1 is locked, and no upstream OFDMA channels are locked.

Xfinity gigabit service actually has a “maximum download speed {of} 940 Mbps when hardwired via Ethernet,” which is within the DOCSIS 3.0 specifications of 960 Mbps.  Thus, it is possible that Xfinity customers on the gigabit plan might be receiving DOCSIS 3.0 service and missing DOCSIS 3.1 features such as Active Queue Management.

Thank you for your assistance.

[plemans · Accepted solution]

The OFDMA channel locked is the docsis 3.1 service. 

Only the downstream locks as its the only one needed. 

I've got the same service and it basically is setup the same. 

Are you having an issue or just checking? 

[plemans · Accepted solution]

The OFDMA channel locked is the docsis 3.1 service. 

Only the downstream locks as its the only one needed. 

I've got the same service and it basically is setup the same. 

Are you having an issue or just checking? 

[Topology]

Plemans, thank you for your reply. Yes, I suspected that the OFDM channel lock was indicative of DOCSIS 3.1 service.

In addition, for Xfinity customers, it is possible to confirm the version of DOCSIS service at an address by:

1. Opening https://www.xfinity.com/support/devices/
2. Entering the service address, picking a download speed of 1000Mbps, and selecting “Find Devices.”
3. In the list of compatible cable modems that next appears, select “View Details” for the modem you have (or intend to purchase).
4. The DOCSIS version is displayed on the page which then appears.

Finally, the following article states that DOCSIS 3.1 is required for Xfinity 1000Mbps service: https://www.xfinity.com/support/articles/requirements-to-run-xfinity-internet-service. Hence, Xfinity customers with a 1000Mbps connection must therefore be receiving DOCSIS 3.1 service.

P.S.: No issues – “just checking.”