cm600 won't negotiate 800down/100up

[greeno]

hi,

gear: cm600, firmware V1.01.22, latest approved by xfinity.

router is ubiquiti ER-X (1gig cable aggregate).

xfinity super fast, 800down/100up, purchased plan.  we just went from a triple play to a double play so i'm paying attention to the plan and what i'm actually getting.

i've been through 2 rounds of xfinity cs. on the wired connection my system speed tests at 300-500 down, 20-25up on a newer macbook pro 1gig capable.

they claim the provisioning went normally and i'm all 'green' at their end.  yet i'm not getting what i paid for.  they're trying to point the finger at at netgear and the cm600. so here i am asking for community help.

on the cable modem signal levels on the downstream channels are fine, 3.5dBmV.  only 4 of 8 upstream channels are bonded.  those are also at 3.5dBmV.

is this a known issue?  is xfinity just pointing a finger?  i did get them to send a tech to check the lines outside the house because i didn't receive the text message after the first round of trouble shooting was complete, the 1 hour long testing.

i am tempted to buy the cm700 to show them the issue is with them.  i do not want nor should i have to use their modem, and pay for it.  

other thoughts?  i've attached screenshots of the the cable modem diagnostics.

thanks,

jeff

[plemans]

I'd be betting on it being that modem. Xfinity just bumped up their upload speeds but only on midsplit/highsplit devices. 

The cm600 (and the cm700) won't cut it currently. 

knowledgebase/next-generation-internet - Comcast_Xfinity (reddit.com)

If you're shopping for a new modem, I'd look for at least a docsis 3.1 device.

[greeno]

thank you for that link.  the modem is 1gig capable and docsis 3.0 (3.1 isn't that different).  i see a  cm1100 for a pretty good price on amazon.  i'll buy it and try it.  thanks for the reply.

jeff

[plemans]

the cm600 is only a 24x8 docsis 3.0 device. While the specs say up to 1 gig, xfinity doesn't certify it to those speeds. 

Its only the docsis 3.1 devices they certify up to 1 gig. Even the cm700, which is a 32x8 modem, isn't gigabit certified. It can hit 900mbps but itsn't certified for it through xifnity. 

A CM1100 is a good option. I've got one and its a solid device

[greeno]

I just order the cm1100.
It’s still annoying that they’ve essentially blacklisted my cm600 so they it can’t be provisioned to 400/100.

[greeno]

i'm in a similar situation with a CM600.  the modem is locked to a 400mbps down/ 20mbps up profile and cannot be re-provisitioned to the 800/100 i pay for.  CM600 is docsis 3.0.  to get the profile/speed i pay for i have to upgrade to a docsis 3.1 model.  just purchased a CM1100.

best,

jeff

[plemans]

Hope it works well for you!

[greeno]

Comcast tech came out. First informed me that only their modem and some hitrons will give more than 25mbps up. Comcast locks it at this. Vendors and Comcast have not agreed on a spec for the upstream bonding.
We verified at the modem I’m getting more than 800mbps down. At the router I’m getting have that. The switch in the edgerouter-x is cutting the bandwidth.
I dropped in openwrt and that removed the switch overhead.
So we wait for netgear and comcast to agree on the upstream spec.
Best,
Jeff

[plemans]

Crapcast tech's are known to be FOSs. I've got a CM1100 and hit 40 Mbps with it. No problem at all. So the 25mbps is bs. 

They're slowly rolling out increased upload speeds. 

but with what he said, I'd be suspicious of anything else he/she said to you. 

https://assets.xfinity.com/assets/dotcom/projects/cix-4997_compatible-devices/2023.09.17%20Full%20Li...

[greeno]

Believe me I’m suspicious. I showed him that page and he said notice they don’t state an upspeed, just down. If you’re getting more I’m jealous.
And in case netgear is listening, I have an option that is cheaper and guaranteed to work, hitron coda. $100. Hitron CODA DOCSIS 3.1 Modem | Pairs with Any WiFi Router or Mesh WiFi | Certified with Comcast Xfinity, Charter Spectrum, Cox | 10x Faster Than DOCSIS 3.0 | Cable Modem with 2X 1 Gbps Ethernet Ports https://www.amazon.com/dp/B0981553MT?ref_=cm_sw_r_apin_dp_V4YPNV9QSP95ACHA4X3D&language=en-US
I paid $155 for a brand new cm1100 directly from Amazon…
As a customer I’m unhappy regardless of the real reason. I’m a brand loyal guy and netgear for cable modems has been my go to for the last 2 products. Wireless ap’s before that…
I can see it in the logs that the cm1100 is unhappy with the upstream comcast node… I posted the critical message previously.

[greeno]

Oh and I’ll add that when cm1100 ‘works’ on Comcast’s network, it’ll easily beat the Hitron up speeds. So I’m inclined to wait a bit. I’m getting the full 800mbps to the lan after dropping openwrt into my ubiquiti er-x yesterday which is a working/correct hw offload for the er-x switch. So that’s a success!

[greeno]

Meanwhile I’m not getting the product I’m paying for, the upload speed. It’s been months 3 months (that I know of) and counting…

[FURRYe38]

And is the CM1100 the model modem your currently using with your ISP? 

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@greeno wrote:
Meanwhile I’m not getting the product I’m paying for, the upload speed. It’s been months 3 months (that I know of) and counting…

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[greeno]

Yes, NETGEAR Nighthawk Multi-Gig Cable Modem (CM1100) - Compatible With All Cable Providers Incl. Xfinity, Spectrum, Cox - For Cable Plans Up To 2Gbps – 2 x 1G Ethernet Ports - DOCSIS 3.1 https://a.co/d/03URddu

[FURRYe38]

What Firmware version is currently loaded?
Please post a copy and paste of the modems connection status and event log page.
https://kb.netgear.com/30007/How-do-I-obtain-the-cable-connection-information-from-a-NETGEAR-cable-m...
https://kb.netgear.com/30008/How-do-I-view-or-clear-the-event-logs-on-my-NETGEAR-cable-modem-or-mode...

Yes I have this modem as well, though not currently online. 

Be sure your using a good quality LAN cable between the modem and router. CAT6 is recommended. 
What is the brand and model of the host wifi router connected to the modem?

[greeno]

I’ll post the currrent firmware and connection status when I’m home.

I’m connected to an edge router-x running openwrt current stable release. I moved from edge os because using the internal switch between ports was costing me 2x in bandwidth. No hit with openwrt.
I get full 800mbps down connected to the router and to the modem. 25 up with either connection. Cables are all cat6. WiFi is served with ubiquiti APs served by a cloudkey 2.

[FURRYe38]

So with a direct connection to the CM1100 modem and no router connected, PC is not getting to spec speeds?

Please post the two data logs when you get time.

[plemans]

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@greeno wrote:

I get full 800mbps down connected to the router and to the modem. 25 up with either connection. Cables are all cat6. WiFi is served with ubiquiti APs served by a cloudkey 2.

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If you're gettign 800mbps download and you pay for 800mbps then you're upload is only 20mbps (25mbps with over provisioning). 

https://www.reddit.com/r/Comcast_Xfinity/wiki/knowledgebase/next-generation-internet/

The cm1100 isn't a "next generation" device. It might get added but it isn't approved currently. 

So if you're getting 800/25, you're hitting your paid for speeds. 

[FURRYe38]

Some correctables that should be zeros. 

Any Criticals, Errors or Warnings seen in the event logs needs to be reviewed and resolved by the ISP. Indicates a signal issue on the ISP line up to the modem.