Gigabit Extra upload speed dropped from ~40 Mbps to ~20 Mbps after Xfinity network upgrade — severe upload latency

I have Xfinity Gigabit Extra. Before the recent Xfinity network upgrade in my area, I consistently received approximately 40 Mbps upload. Since the upgrade, my upload speed has consistently been approximately 20 Mbps, regardless of the time of day.

I recently ran Waveform's Bufferbloat test and found a significant difference between my two Internet connections:

Xfinity: approximately 559 ms upload latency under load

AT&T: approximately 63 ms upload latency under load

I have both Xfinity and AT&T Internet/Wi-Fi in my home. I ran the tests on the same computer, in the same home, using the same Waveform test. The Internet connection is the primary variable that changes between the two tests.

My Xfinity idle latency is otherwise good (approximately 41 ms), and my download speed is approximately 250 Mbps. My Zoom video calls also work normally, so I am not experiencing an obvious day-to-day service problem. However, the combination of the consistent 20 Mbps upload ceiling and the very high upload latency under load concerns me.

Because the upload speed decreased from approximately 40 Mbps to approximately 20 Mbps following the Xfinity network upgrade, and because the AT&T connection does not exhibit the same severe upload latency, I would like to have Xfinity investigate whether there is an upstream provisioning, modem configuration, or network configuration issue associated with my Gigabit Extra service.

Could an Xfinity technical representative please verify that my account and modem are correctly provisioned for the upstream service available in my area, and determine why my upload speed is now limited to approximately 20 Mbps?

I am happy to provide account-specific information through a private Xfinity Support message if necessary.

Responses

Oldest First

Selected Oldest First

XfinityPaula

Official Employee

•

2.4K Messages

7 days ago

user_hn6lfu Hello there! Thank you for reaching out to us about the slow upload trouble we are having since the work was completed in the area. I'm sorry that the speed has decreased by half for the upload. I'm sure this is putting a damper on something functioning even if it's not that apparent for your typical uses. I am also concerned with the download speed that you shared considering you have our gigabit extra speed tier. The download should be over a gigabit or at least close to it even with a compatible Wi-Fi device.

When I start to notice connection and speed issues the first thing I do is turn off the modem and wireless mesh system that we use. Allowing the modem to reboot allows it to check for the latest firmware, if a new one is available and obtain the latest account service especially if your area was recently enhanced to obtain the new speeds.

I love that you have the two connections available in your home, that makes testing and troubleshooting easier especially is we are seeing issues with a specific device or web address.

With your Xfinity internet connections, do you have a wireless router or wireless mesh system connected to the modem, or are you using a wireless gateway? I would like, if possible, to test the Xfinity connect with an ethernet cable connected directly to the modem or gateway. This helps us remove any other potential device issues from the connection to get a solid reading on service that is reaching the modem.

5

0

U

user_hn6lfu

Visitor

•

4 Messages

Hi Paula,

Thanks for your response.

As you suggested, I turned off the cable modem and the wi-Fi router. I reran both Speedtest by Ookla and Bufferbloat by Waveform after that, and the results did not change from what I had in my original post.

I don't have a wireless mesh system.

Here is the equipment that I have:

Netgear Router

AC1750 Smart WiFi Router

Model R6400

Netgear Cable Modem

Model CM1000

Unfortunately, I have a Lenovo ThinkPad laptop that does not have an Ethernet port.

I am not a technical expert, but the fact that uploads used to run twice as fast and with normal latency with the same cable modem and Wi-Fi router before you did an upgrade to your network would indicate to me that the problem might be related to my modem/gateway configuration, upstream provisioning, DOCSIS connection, or other parts of the Xfinity network itself.

If you need any additional information to troubleshoot further, please let me know. Otherwise, I look forward to your suggestions on next steps.

Like

Reply

7 days ago

0

XfinityPaula

Official Employee

•

2.4K Messages

user_hn6lfu Please forgive our delay. Thank you for taking the time to reset the modem and router. I completely understand how the trouble seems isolated to the area work that was completed considering the timing of the slow speeds starting.

I would love to take a closer look into things and help get us back to the speeds we should see.

Can you please send us a direct message with your name and service address?

From there I can verify the account and check on the provisioning and see if there are any other issues being reported for the area.

Here are the detailed steps to direct message us:
Click "Sign In" if necessary
Click the "Direct Messaging" icon
Click the "Start new conversation" (pencil and paper) icon
In the "To:" line, type "Xfinity Support"
As you type, a drop-down list will appear. Select "Xfinity Support" from that list.
A "Xfinity Support" graphic will replace the "To:" line.
Type your message in the text area near the bottom of the window.
Press Enter to send it.
How to: https://forums.xfinity.com/conversations/guidelines/how-to-direct-messaging-within-the-forum/697ba1e570934d009185c514

I am an Official Xfinity Employee.
Official Employees are from multiple teams within Xfinity: CARE, Product, Leadership.
We ask that you post publicly so people with similar questions may benefit from the conversation.
Was your question answered? Please mark as Best Answer. tick

Like

Reply

5 days ago

0

U

user_hn6lfu

Visitor

•

4 Messages

You should have the information you requested on your side via direct message. Thank you!

Like

Reply

5 days ago

0

XfinityPaula

Official Employee

•

2.4K Messages

user_hn6lfu Thank you, I am following up with you in the direct message now.

I am an Official Xfinity Employee.
Official Employees are from multiple teams within Xfinity: CARE, Product, Leadership.
We ask that you post publicly so people with similar questions may benefit from the conversation.
Was your question answered? Please mark as Best Answer. tick

Like

Reply

5 days ago

0

Your Home Network

user_hn6lfu

Gigabit Extra upload speed dropped from ~40 Mbps to ~20 Mbps after Xfinity network upgrade — severe upload latency

XfinityPaula

user_hn6lfu

XfinityPaula

user_hn6lfu

XfinityPaula

New to the Community?