XB-7 does not provide HIGH SPEED, reverts to the slower speed

I upgraded from a XB-3 to XB-7. I've had the same IP address for 7 years....but upon the upgrade it issued me a new IP address, but the Ubiquiti router does not recognize that 174.xx.xxx.xxx address and reverts back to the OLD WAN address 73.x.xxx.xx- which is based on a slower Internet speed.

All the above is based on a LAN not WiFi.

When we revert to NON BRIDGE MODE, the speed is in excess of 900mb/s in Bridge mode it is about 350mb/s which was the internet speed before the XB7.

Any chance one of you company or volunteer techs can help identify the problem?

I've resorted back to the old IP and Speed, but would really like to get the higher speed I'm willing to pay for.

Thanks

Responses

Accepted Solution

Phast1

Contributor

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24 Messages

3 years ago

Problem SOLVED....now at over 700mb/s with the 600mb/s service....

Issue was in MY router which required a change to operating system.

thanks all for your replies.

Phil

Hemingray42

Contributor

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76 Messages

3 years ago

Xfinity's IPv4 addresses commonly start with either 68 or 73.

174 sounds like a Verizon Wireless IP. Did you put the XB7 in bridge mode?

Phast1

Contributor

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24 Messages

@Hemingray42 Just for the record....do a search for the 174.xxx. WAN address and you will see it is assigned to Comcast in Jacksonville FL.

3 years ago

BruceW

Gold Problem Solver

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26.2K Messages

3 years ago

Xfinity's IPv4 addresses commonly start with either 68 or 73 ...

A number of "174" IPs are assigned to Comcast. All of 174.60.x.y, for example, along with several other ranges.

BruceW

Gold Problem Solver

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26.2K Messages

3 years ago

... I upgraded from a XB-3 to XB-7 ... it issued me a new IP address ... 174.xx.xxx.xxx address ... reverts back to ... 73.x.xxx.xx- which is based on a slower Internet speed. ...

I don't know why your speed is dropping when you switch from router mode to bridge mode, but the change in IP address is incidental -- it's not a cause of the problem. The IP address is not at all related to speed.

The IP address assigned in cable Internet depends on the first MAC address the modem "sees". When an all-in-one modem/router gateway device like the XB3 or XB7 is in router mode, its modem component "sees" the MAC address of the gateway's internal router. When the gateway is in bridge mode, the internal router is disabled and the modem component "sees" the MAC address of your external router.

When the "seen" MAC address changes, the IP address changes. That's normal and expected, and it's why your IP address changes when you switch between router mode and bridge mode.

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...") the author of the post you are Commenting on is notified of your response. But if you select Reply, the author of the post you are Replying to is NOT notified and may not be aware of your response.

(edited)

Phast1

Contributor

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24 Messages

@BruceW Good info Bruce.....understanding the problem is the first step in fixing the problem.

Putting this project behind me, so I can go on to other new issues....

Your input was very helpful.

Phil

3 years ago

Phast1

Contributor

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24 Messages

3 years ago

Hi Bruce,

MORE INFO:

I have the XB7 in Bridge mode....plugged into a Windows laptop, I get the 900+ speed and the IP is shown as xxx.xx.224.191, of course the laptop has different MAC address than the Ubiquiti router I'm using use....which is set for the WAN port as DHCP.

When I reboot the Xb7, and plug in the Ubiquiti router, it reverts back to the OLD IP of xx.0.xxx.84 - and the slower speed.

My GUESS is the Comcast network is recognizing the MAC address of the Ubiquiti router and 'connects' it to the OLD IP address which is provisioned for the XB3 at the slower speed.

So, what I need is someone at the Comcast side to clear out the OLD MAC address from the system and allow the DHCP of the XB7 to request a NEW WAN IP address.

Thoughts?

BTW I'm a retired fiber engineer, and my expertise is in the physical layer not the IP layer...so I'm hoping someone can figure this out for me - so far calls to Tech Support have got me nowhere...they keep pointing to MY equipment as the issue.

thanks

Phil

EG

Expert

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108.3K Messages

@Phast1

My GUESS is the Comcast network is recognizing the MAC address of the Ubiquiti router and 'connects' it to the OLD IP address which is provisioned for the XB3 at the slower speed.

FWIW. Speed provisioning and IP addresses are unrelated. The connection speed is controlled by the configuration file / boot file that is loaded into the cable modem regardless of the IP address.

Something else is going on here but I don't know what that may be exactly. Sorry.

(edited)

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3 years ago

BruceW

Gold Problem Solver

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26.2K Messages

3 years ago

... and 'connects' it to the OLD IP address which is provisioned for the XB3 at the slower speed. ...

I'm not familiar with Ubiquiti, but most routers provide a way to change their MAC addresses. Since your PC seems to get the speed you are expecting, can you assign your PC's MAC address to the Ubiquiti? It would then pull the same IP address as your PC was using, and you could test you thesis that your Internet speed is connected to your IP address.

(edited)

Phast1

Contributor

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24 Messages

3 years ago

I'm hoping the issue is that I have NOT returned my XB-3 modem, and it is still shown assigned to my account/premise. I'm going to return it tomorrow, Monday, but I'm going to contact my advanced tech support folks....and see if the MAC address of my router is pulling the wrong provisioning - which again I'm guessing is assigned to the XB3. I've tried forcing the WAN IP address of the router to the IP of the laptop, xxxxx.91, which did not not at all, but I'm still thinking it is the MAC address the culprit.

ARE THERE ANY COMCAST ENGINEERS MONITORING THIS THREAD? You input would be helpful.

Bruce....the Ubiquity 10X is a managed router - https://dl.ubnt.com/ds/edgeswitch_x_ds

CCDaryl

Problem Solver

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828 Messages

@Phast1

I wanted to reach out to you about your experience. You mentioned that you were going to return your XB3 a day ago, hoping that would resolve the issue you were experiencing. I wanted to see if you had the chance to do that, and if it worked out the way you wanted it to?

I no longer work for Comcast.

3 years ago

Phast1

Contributor

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24 Messages

HI, Sorry, it did not....I returned the XB-3 yesterday.....today I have two WAN addresses. the 174.xxx is in the XB-7. However the Router is getting the old 73.xxx WAN address and my speed is below 400mb/s. If I Disable Bridge mode and plug in my Windows laptop, I get the rated 900+mb/s speed.

My router is set for the WAN as DHCP, so I would assume it would provision the connection to the new WAN IP and support the higher speed.

Thanks for checking in..... Is there a Tech Support group that can address this issue? It will take someone with the knowledge of IP and inner workings of a router to address the problem......whether it is my issue or Comcast's system.

3 years ago

XfinityEva

Official Employee

•

1.5K Messages

Sorry to hear that did not work out. We'd like to further assist in direct message. Please send us a direct message with your full name and service address to get started.

Click "Sign In" if necessary
Click the "Direct Messaging" icon or https://comca.st/3kajO4e
Click the "New message" (pencil and paper) icon
The "To:" line prompts you to "Type the name of a person". Instead, type "Xfinity Support" there
- As you are typing a drop-down list appears. Select "Xfinity Support" from that list
- An "Xfinity Support" graphic replaces the "To:" line
Type your message in the text area near the bottom of the window
Press Enter to send it

See https://comca.st/2XfS9FQ for an example.

(Full credit to @BruceW for this excellent explanation!)

I am an Official Xfinity Employee.
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3 years ago

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XB-7 does not provide HIGH SPEED, reverts to the slower speed

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