U

Visitor

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7 Messages

Sunday, February 19th, 2023 6:49 PM

Closed

Verizon 4G LTE Extender Hangs on Connection to Verizon SeGW Server on Xfinity Xfi Home Network

I’m having problems getting a Verizon 4G LTE Extender to work on my Xfinity Xfi Home Network.  The 4G LTE Extender box keeps “hanging” on connecting to the Verizon SeGW Server on Port 4500.  It connects, but then disconnects and status is “Authorization Failure”.  It does this every 15 seconds.

The Extender box, upon startup, goes thru Hardware & Software Initializations, and then connects to my Xfinity Xfi Router/Modem.  It then establishes coverage from a multitude/adequate number of GPS Satellites, but then gets “hung” connecting to the Verizon SeGW Server on Port 4500.

I’ve been on the Verizon and Xfinity support lines a “gazillion” times.  They each point the “finger” at each other!  Verizon says that Xfinity needs to “unlock” certain Ports for this to work.  Xfinity says that the required Ports are not blocked.  Verizon also says that the 4G LTE Extender is “registered”, so it should have no problem getting into the SeGW Server.

Verizon provided me the following Ports/Settings that are needed to make the Extender work:

­

Ports:

  • UDP 319
  • UDP 320
  • UDP 500
  • UDP 4500
  • UDP 52428 + 20906
  • TCP/UDP 443 + 80

Other Settings:

  • Make sure ESP packets are not blocked by the firewall on the downstream
  • Enable high QoS for the Femto (LTE Extender)
  • Make sure MTU Size is set to 1448 or higher
  • Enable DMZ: recommended. NOT required.  Common on most consumer routers.

I talked to Xfinity and they say that all the above should be OK, without any problem.

I tried playing around with the Xfi Router Firewall – doesn’t make a difference.  Also, I tried Port Forwarding and Port Triggering for the above Ports and putting the Verizon 4G LTE Extender in the Router DMZ, and none of those solve the problem.

I gotta believe that across the USA that there are many people that have the Verizon 4G LTE Extender working with an Xfinity Xfi Home Network !!

Am I missing something?  I also can’t believe that Verizon and/or Xfinity can’t resolve this issue.

Any help from anyone would be much appreciated… Thanks much…

Problem Solver

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322 Messages

2 years ago

@user_ef9871 Thank you for reaching out to us, if you are still having issues with connecting your extender to your Xfinity wireless gateway please send us a direct message with your name and complete service address for assistance. 

To send a "Direct Message" to Xfinity Support:

Click "Sign In" if necessary

Click the "Direct Messaging" icon or https://comca.st/3EqVMu7

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

Expert

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108.3K Messages

2 years ago

The concern is not "Xfinity Home Security / Devices And Equipment" help related. Topic moved here to the proper help section for assistance. 

Visitor

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7 Messages

@EG​ 

OK.  Thx much for moving this.

I am a "newbie" to this Forum.  I thought I already was posting publicly.  Did I miss something?

Per the previous reply, I followed the instructions provided and did the Direct Messaging to Xfinity Support.

Thx again...

Expert

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108.3K Messages

2 years ago

@user_ef9871 

No worries ! Disregard those poorly worded sigs. You did post publicly. Yer' good !

Visitor

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7 Messages

@EG​ 

OK. Good.  Thx again for your reply to this.

Visitor

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7 Messages

Does anyone know if the Xfi Router/Modem allows for IPSec Passthrough?  And/or is NAT/PAT supported in the Xfi Router/Modem?

Problem Solver

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1.5K Messages

@user_ef9871​  I wouldn't bank on a cost reduced Xfinity gateway being able to handle jumbo frame packets (larger than 1500 MTU).  IPSec adds 20 bytes to the header, and 50-60 bytes of payload, so 1500-40=1460 bytes off the top, and then you got your payload to consider -- varies with specific protocol.

Wireshark/Pcap capture some traffic and see what you are sending.

Visitor

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7 Messages

Thx for reply.

I'm not a networking person, so I'm not sure what that all means.  Verizon told me Extender needs 1448 MTU or higher.  Extender default is 1448.  I tried setting it to 1500, which is what Xfinity told me the Xfi Modem/Router runs at.  When I set 1500 in the Extender, it didn't make a difference.

Again, I'm a Newbie on this.  How do I acquire & run Wireshark/Pcap ?

Problem Solver

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1.5K Messages

@user_ef9871​  Wireshark.org.  Take a look at the documentation.  You want to sniff the traffic coming out of the extender and see what it's sending.

Leave the extender default at 1448.  They're probably already accounting for their own packet overhead so you don't exceed 1500 for a packet size.

The other problem you get with Xfinity gear, is port forwarding is awfully screwed up, so if you end up needing it, it might work and it might not.  Results are pretty mixed here. 

First thing to check.  Is the extender even getting an IP address on your network, and do you have it set to get an IP address with DHCP?  Is it getting the address you think the port forwards are going to?  (yet another Xfinity oddity).


Visitor

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1 Message

2 years ago

@user_ef9871 Have you been able to get your extender activated and if so, did you just purchase an extender directly from Verizon?

Myself and other forum users have contacted XM support multiple times only to be told that 4g/lte extenders are not supported on XM network which I know is complete  [Edited: "Language"] since my Verizon issued extender worked great (4 to 5 bars) on XM’s network for a week or 2 when I first switched to XM. Unfortunately, VZW deactivated my extender once I deactivated my last VZW phone line.

I completely agree that it’s amazing that XM/VZW can’t put a simple process in place to support the activation. 

(edited)

Visitor

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7 Messages

@user_78efdf​ Thx for inputs..... I totally concur !!!

Problem Solver

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1.5K Messages

2 years ago

Just for a sanity check, have you tried something else on the Ethernet ports on your gateway?  A few reports of Ethernet ports not working right.  If you are on the port with the orange or red stripe and you can't get an IP address with whatever device you plug in, try another port.

Looks like your extender initiates the contact, so you really shouldn't even need to blow holes in your firewall for it.  Default pass rule should allow that.  Another quick thing is if you have "advanced security" turned on, try disabling that with the phone app.  Xfinity gear is super buggy.

Visitor

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7 Messages

@flatlander3​ Thx for your reply and inputs....

I did try plugging Extender into the other Ethernet ports on the Xfi Modem/Router and it didn't make a difference.

Also - I don't have Advance Security on.  Never have.  Was thinking about it, but wasn't sure if I really needed it without some additional looks at it !

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