What is happening with 3G?
BarbaraC1977's profile

Contributor

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3 Messages

Saturday, August 29th, 2015 9:53 PM

Solution for Microcell with Xfinity Modem & Linksys router

I had trouble activating my microcell--it was stuck doing NOTHING, after following directions carefully three or four times.  AT&T secondary support verified I was doing all the required steps, and sent me to my ISP.  It took a while to get to their (really) technical support, but after I did, Joe listened to the requirements AT&T posted on this page: AT&T Microcell Firewall and Router Settings for Advanced Installations.  He took a different approach, and changed our Xfinity Modem, connected directly to our Linksys Wifi & Ethernet router, to "Bridge Mode."

 

After doing all the power-down, restarts of the modem, router, and Microcell, I then disconnected the microcell from my AT&T account, and re-linked it, starting the process again.  SUCCESS!!!

 

I'm posting this to help others, rather than to ask a question.

Accepted Solution

Official Solution

Avedis53

Professor

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2.2K Messages

7 years ago

You do not mention the make and models of your "modem" and router but from what you've described, I would say that your "modem" is a gateway (combined modem/router).

 

Connecting a router to a gateway with both units having DHCP server capabilities enabled can create what is called a double NAT conflict.  The Mcell does not play well with a double NAT network.

 

The Comcast tech put the Xfinity gateway into bridge mode which disables its DHCP server and allows your Linksys router to handle all the DHCP duties.

 

We have seen this many times around here.  Thank you for your post!!

Contributor

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3 Messages

7 years ago

By the way, my phone went from 1-2 bars in the house to 5!  I'm SO pleased, finally.

Avedis53

Professor

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2.2K Messages

7 years ago

Glad to hear that your Mcell is working for you now.  If you have any questions or problems, you know where to find us.

Contributor

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3 Messages

7 years ago

Modem is an Arris TG862, and Router is Linksys EA6350.  Sorry for not including those.  Microcell is Cisco DPH-154.

Avedis53

Professor

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2.2K Messages

7 years ago

That confirms my original suspicion.  The Arris TG862 is a telephony gateway (hence the TG) and would need to be put into bridge mode to resolve your NAT conflict.  Thanks for the info.

OttoPylot

ACE - Expert

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19.6K Messages

7 years ago

Whoo Hoo! Thanks Avedis53. A double NAT gets them everytime.

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