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Visitor

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8 Messages

Wednesday, August 14th, 2024 12:58 AM

Xfinity X2 Upstream speeds

On August 5th I upgraded to Xfinity/Comcast Gig X2 service because my Gig+ contract had expired and being retired, my funds are limited. Gig X2 is supposed to provide 2Gbps down and 300Mbps up.

Unfortunately, after the new service was provisioned (and the contract was initiated), I discovered that my Motorola MB8611 Modem was capped at 41Mbps upload. The reason for that is that although the MB8611 is a DOCSIS 3.1 modem and capable of up to 2Gbps up, this modem would have to have received recent firmware upgrades which support orthogonal frequency division multiplexing (OFDM) on the upstream side. Presently OFDM is only supported downstream. That being said, the MB8611 has fallen off of the Xfinity recommended/preferred list since Motorola has ceased to support upgraded firmware for it.

So, I purchased the new Arris Surfboard S33 DOCSIS 3.1 modem which arrived today. I provisioned it and I have 2Gbps downstream and 41Mbps upstream which is the same upstream speed I had on the old modem.

After talking to Xfinity Technical support for two hours and being elevated to a supervisor, I learned that the upstream speed is only 300Mbps if you are using an Xfinity X-Fi Gateway. Translation: They have not updated the upstream provisioning code for customer provided modems yet. There is no timeframe for this according to the supervisor that I spoke with.  They offered to replace my UDM Pro with an X-Fi gateway which is a nonstarter with my seven VLANs, multiple site to site VPN's, 120 switch ports and so on.  I run a YouTube tech channel and my upstream speed is critical and the reason I opted for the new contract for two years.

There is nothing in the product description and nothing that the sales folks said that led me to believe that  the 300Mbps upstream was not an expected feature with the Arris modem which is listed as both a preferred and recommended device.  In fact, the sales person on the phone who updated my contract told me that in the last two weeks that Gig X2 was offering 300Mbps as a new feature and was a huge improvement over the 200Mbps offered initially.

I was told that I would get 40Mbps only because I had a customer provided modem. So, I regard this as misrepresentation of the product/service being sold. The reason the the X-Fi Gateway is pushed is because it segments off a dedicated portion of bandwidth for a "public" Xfinity Wifi service for every customer that has this gateway. Their gateway does not support VLAN's, inbound/outbound custom VPN's, failover WAN connections, site to site VPN, and a plethora of other features I require. They also indicated they would not provide any "discount" on the service. I renewed my Xfinity contract for X2 service because it was the next higher service. Had I stuck with Gig Plus, I would have been paying $141 a month.

As it is, I have to pay $30 each month for "unlimited" data because I exceed the 1200GB per month cap (upload and downloads added). So, by getting this two year contract, my bill is $115 a month which is $10 more that I was paying, but I do have twice the download speed. The catch is they advertised in writing that I would get 300Mbps downstream and not the 40Mbps downstream I have. So, their point is I could go with their X-Fi Gateway and get the 300. What is really happening here is that they recoded the provisioning file on the download side, but not the upload side. They recoded the upload side only for their X-Fi device.

This is a bait and switch which I am inclined to report to the BBB since even the graphic from the website pictured above says my service is 2000/300.  I can't use an X-fi gateway for my use case.  I am livid that I bought the new Arris Surfboard S33 for $198 and I still have only 40Mbps upstream despite Xfinity's own documentation that says they support 300Mbps.  I don't like AT&T, but their non-contract regular price for 1Gbps symmetric service is only $79 with no data cap.  My price for the X2 service is $115 because 1200GB's amonth just doesn't work for my wife and I who watch 4k streaming all day long and my YouTube channel uploads.  We are retired and have mobility issues and $115 a month is just not competitive in the market.  Even less so if Xfinity doesn't deliver what is promised. 

Gold Problem Solver

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26K Messages

3 months ago

... the upstream speed is only 300Mbps if you are using an Xfinity X-Fi Gateway ...

That's not quite correct. There are a few retail devices on their "Next Gen Speed Tier" list that are compatible with the new higher upload speeds, although neither of the modems you mentioned are on it. See:

Realize that although Comcast calls some devices "Compatible" and some "Recommended", for all but a few devices those designations only mean "compatible/recommended for use with their Internet service", and not necessarily approved for the new upload speeds.

You need one of Comcast's newer rental gateways (XB6, XB7, XB8) or one of the few retail devices shown in the "Next Gen Speed Tier" group with an upload speed rating in the "All Compatible Devices" PDF.  Also see the Reddit link, which lists the approved devices as well as other requirements for faster upload speeds.

Comcast could make all of this much clearer, but they have chosen not to do so.

Please be aware that there are 2 kinds of responses in this Forum: Replies and Comments. When you Comment on a post by scrolling down to "Comment on this post here...", I am notified of your response. But if you select Reply, I am NOT notified and may not be aware of your response.

Visitor

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8 Messages

@BruceW You missed the point.  I don't want, nor can I use a combo router device.  I have $20k of equipment in my main rack and I want a cable modem to be a modem only and not a router or an access point or "gateway" as you put it.  The Arris Surfboard S33v2 is on the official recommended list at https://assets.xfinity.com/assets/dotcom/projects/cix-4997_compatible-devices/2023.11.22%20Full%20List%20of%20Compatible%20Devices.pdf.

My issue is the deliberate throttling of my upstream speed to only 41Mbps when the advertised service speed is 300Mbps.  It is not only apparent, but obvious that the upstream portion of the provisioning file has been changed on X-Fi Gateways, but deliberately restricted to 41Mbps on customer owned devices even if they are on the list.  Nothing in the service agreement or contract says that I should expect less than the 300Mbps advertised.  The sales person knew my current modem and said that I would really appreciate the they recently upgraded the X2 service from 200Mbps to 300Mbps.

Again, my profile page even says 2000Mbps download and 300Mbps upload.

(edited)

Expert

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107.1K Messages

3 months ago

@BruceW is right. Did you see the PDF ? These are currently the only retail cable modems that they will provision for the Next Gen upload speeds;

Visitor

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8 Messages

Then what is this???  Also, is there anyone that can confirm that any modem device (not router) can provide the advertised 300Mbps upstream before I buy ten more of these to test?

(edited)

Visitor

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8 Messages

I ended up buying the Netgear CM3000.  Ultimately it worked.  When you first get it provisioned, it only gets 60Mbps up.  Wait a day and then it finally kicks in and gives you the 300Mbps.  No one at Xfinity has the right information and there are multiple of these standards tables.

Official Employee

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1.1K Messages

@user_eb4992 Thanks for the update. I am glad to know you're receiving the correct speeds with your new modem. I recommend starting at this page from our help and support site https://www.xfinity.com/support/articles/list-of-approved-cable-modems to locate the approved modems for your service. 
Did you have any additional questions for us?

 

(edited)

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Gold Problem Solver

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26K Messages

3 months ago

... I don't want, nor can I use a combo router device ...

Sorry to disappoint. Note that the retail modem list you posted is from last year. The current list, as stated above, is the one posted at https://assets.xfinity.com/assets/dotcom/projects/cix-4997_compatible-devices/2024-07-18_Full-List-of-Compatible-Devices.pdf (changes from time to time).

Also, as stated above, Comcast calls some devices "Compatible" and some "Recommended", but for all but a few devices those designations only mean "compatible/recommended for use with their Internet service", and not necessarily approved for the new upload speeds.

The retail devices compatible the new higher upload speeds are, as stated above, the ones in the "Next Gen Speed Tier" list. There are 4 "Next Gen" modem-only devices on that list which are compatible with the 2 Gbps speed tier:

Next Gen Speed Tier

Model Built-in WiFi Voice Telephone enabled DOCSIS Wired Download Speed Wired Upload Speed
Hitron CODA56 No No DOCSIS 3.1 Up to 2.33 Gbps Up to 455 Mbps
Netgear CM3000 No No DOCSIS 3.1 Up to 2.33 Gbps Up to 486 Mbps
ARRIS / Surfboard S34 No No DOCSIS 3.1 Up to 2.32 Gbps Up to 444 Mbps
Ubiquiti UCI No No DOCSIS 3.1 Up to 2.33 Gbps Up to 474 Mbps

And once again:

If you select Reply, I am NOT notified and may not be aware of your response.

(edited)

Visitor

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8 Messages

You do realize that NONE of the sales people and NONE of the online technical support have any idea that this is an issue.  In fact, when I registered the new ARRIS Surboard S33, the technical support representative told me that was the BEST choice I could have made based on their current recommendations.  I am betting that if I bought the Netgear CM3000 or the ARRIS Surboard S34 mentioned above that I would still not see anything beyond 41Mbps.  None of the script reading offshore support folks had any assurances to offer me in that regard.  My confidence is LOW that yet another modem would make any difference.  The inability to get to senior technical personnel to ask specific questions is a complete failure in both the business and the support model.  

Contributor

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16 Messages

This is an active topic on dslreports.com in the Xfinity section. Short version the list of 3rd party modems supporting >50 mb./sec or so uploads is pretty short. The Arris S34 seems pretty popular there. The Hitron CODA56 has had some hardware issues - there's some sort of fiber heat sink that has disintegrated after a few months in a few cases. Warranty on the CODA56 is 6 months so that could be an issue. People with the skills and experience have replaced the disintegrated heat sink which cured the problem. The Hitron CODA and CODA56 were on Xfinity's preferred list but had some firmware issues (The CODA56 was quite new at the time).

3 Messages

3 months ago

I also have an S34 and it is not working for mid split speeds. I was told by a rep it isn't supported.

Visitor

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8 Messages

I ultimately went with a Netgear CM3000 and I am now seeing 2292 Mbps down and 354 Mbps up on my X2.

(edited)

Problem Solver

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857 Messages

3 months ago

I'm not sure you would get the 300 Mbps with an Xfinity modem either. I was recently given a free upgrade from 75 Mbps to 150 Mbps and for some reason after doing an Xfinity app reboot I'm stuck at 50 Mbps. They told me it must be the modem which was their xb7 and to go swap it out so now I have the xb8 and I'm still stuck at 50 Mbps. Not even the 75 Mbps that I used to get before I got the free upgrade. No one can explain this to me so don't be so sure that even by using the Xfinity provided modem you'll get anything more than you're getting now.

Visitor

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8 Messages

@user_0ih2332​ Now that I am using the Netgear CM3000, I am getting the full 200 Mbps up, plus some.

(edited)

Visitor

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9 Messages

3 months ago

It would probably be most worth it to pay for xFI Complete and use their XB8, then just put it in bridge mode. Then you get unlimited data and can still have your Ubiquiti gear get a public IP.

1 Message

1 month ago

+1 I am dealing with same thing right now.  They've been pushing me to get their spam-ware filled modem

Visitor

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9 Messages

@spatel2​ If you put it in bridge mode then it really isn't a bad deal. I did move over to AT&T Fiber and the best thing they offer is passthrough, which "reissues" your public IP, with the modem still using NAT and holding the true public IP.

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