Router not letting Wi-Fi Calling through

[Deleted member 58331]

Hello,
I have an ASUS RT-AC3100 router on ASUSwrt Merlin 384.4_2, and something seems to be preventing my iPhone from using Wi-Fi Calling.
When on any other network, it works fine, but on my network, the "Wi-Fi Calling" carrier signal shows up only for a second, as if the VPN tunnel is terminated.
I know for sure my network is the problem because I have a personal and a work iPhone on different carriers and the exact same issue is happening.
My ISP is Bell Fibre (Toronto), and it is connecting using PPPoE.
Things I have tried:
- Disabling Firewall on router (so all ports including 500 and 4500 are open)
- Enabling VPN passthrough on router (including IPSec)
- Changing DNS on router
- Enabling IGMP snooping

A TELUS network engineered told me that the request does not even reach their gateway and thus there must be something in the router blocking that.

Anyone can help?

 

[CaptainSTX]

If you are running a VPN client on your router and your Iphone is connecting using the VPN tunnel just for grins connect the iphone to your WiFi without using the VPN.

I should not be causing the problem as I connect my iphone using the VPN and WiFi calling works but in your case maybe something is interferring. If this solves your problem them at least you know the problem is either with your client setup or the VPN provider you are using.

 

[jrmwvu04]

I can’t help, but I have been having issues with this as well. I’m on a different carrier, router, and firmware. I just recently noticed the change, which coincided with installing iOS 11.3 and I assumed that was the cause. But I have no idea really. Will follow the thread to see what is uncovered. No VPN for me, by the way.

 

[FreshJR]

Do you have sip pass through enabled under wan -> Nat passthrough.

Try that.

If that fails, try a port forwarding temporarily.

Also as the user above posted, iOS 11.3 has been set to favor cellular networks and falls back to WiFi calling only in extremely poor signal areas.

Apple in all their wisdom as always made this non configurable since they know best and don't want to confuse the user....

https://www.reddit.com/r/tmobile/comments/7xz4g0/wifi_calling_configured_for_cellularpreferred_on/

It's a terrible change since the bars do not indicate call quality. In fringe areas I can have 2-3 bars but my outgoing connection (my voice) will intermitantly drop for a few seconds at a time.

 

[jrmwvu04]

https://www.reddit.com/r/tmobile/comments/7xz4g0/wifi_calling_configured_for_cellularpreferred_on/

It's a terrible change since the bars do not indicate call quality. In fringe areas I can have 2-3 bars but my outgoing connection (my voice) will intermitantly drop for a few seconds at a time.

I just got done reading that thread as well, interestingly. Mystety solved, at least.

 

[Deleted member 58331]

If you are running a VPN client on your router and your Iphone is connecting using the VPN tunnel just for grins connect the iphone to your WiFi without using the VPN.

I should not be causing the problem as I connect my iphone using the VPN and WiFi calling works but in your case maybe something is interferring. If this solves your problem them at least you know the problem is either with your client setup or the VPN provider you are using.

I am not running a VPN client on my router.

Do you have sip pass through enabled under wan -> Nat passthrough.

Try that.

If that fails, try a port forwarding temporarily.

Also as the user above posted, iOS 11.3 has been set to favor cellular networks and falls back to WiFi calling only in extremely poor signal areas.

Apple in all their wisdom as always made this non configurable since they know best and don't want to confuse the user....

https://www.reddit.com/r/tmobile/comments/7xz4g0/wifi_calling_configured_for_cellularpreferred_on/

It's a terrible change since the bars do not indicate call quality. In fringe areas I can have 2-3 bars but my outgoing connection (my voice) will intermitantly drop for a few seconds at a time.

Passthrought for everything is already enabled, and I tried disabling the Firewall like stated in my OP.
Also, putting in Airplane Mode forces Wi-Fi Calling in iOS no matter the signal level, confirmed by a TELUS network engineered.

I just got done reading that thread as well, interestingly. Mystety solved, at least.

... The mystery is not solved. If I connect to my neighbour's Wi-Fi from the same location, the Wi-Fi Calling kicks in, so it's not about the cellular signal level.

 

[RMerlin]

Hello,
I have an ASUS RT-AC3100 router on ASUSwrt Merlin 384.4_2, and something seems to be preventing my iPhone from using Wi-Fi Calling.
When on any other network, it works fine, but on my network, the "Wi-Fi Calling" carrier signal shows up only for a second, as if the VPN tunnel is terminated.
I know for sure my network is the problem because I have a personal and a work iPhone on different carriers and the exact same issue is happening.
My ISP is Bell Fibre (Toronto), and it is connecting using PPPoE.
Things I have tried:
- Disabling Firewall on router (so all ports including 500 and 4500 are open)
- Enabling VPN passthrough on router (including IPSec)
- Changing DNS on router
- Enabling IGMP snooping

A TELUS network engineered told me that the request does not even reach their gateway and thus there must be something in the router blocking that.

Anyone can help?

Try enabling IPSEC passthrough under WAN -> NAT Passthrough.

 

[Deleted member 58331]

Try enabling IPSEC passthrough under WAN -> NAT Passthrough.

It's already on

 

[Striker317]

FWIW iphones using the same router as the OP on Rogers internet here connect no problem to Wifi calling.

 

[FreshJR]

FWIW iphones using the same router as the OP on Rogers internet here connect no problem to Wifi calling.

The wifi calling change introduced in 11.3 is carrier specific and part of the provider supplied carrier bundle under general -> about

 

[Deleted member 58331]

The wifi calling change introduced in 11.3 is carrier specific and part of the provider supplied carrier bundle under general -> about

Both of my iPhones, on two different carriers are having the same issue.

 

[FreshJR]

Both of my iPhones, on two different carriers are having the same issue.

First apply a port forward on 500,4500 applied to one of the iPhones to see if it's a iOS change or a router NAT issue.

 

[jrmwvu04]

The mystery is not solved.

Well, mine is. The change was included in iOS 11.3 for T-Mobile and is now expected behavior, so that’s that on my end.

 

[Deleted member 58331]

First apply a port forward on 500,4500 leading to one of the iPhones to see if it's a iOS change or a router NAT issue.

Lmao sorry y'all, but please read my original post!
I took the time to list everything I have already tried but everyone is suggesting me things I have already tried and listed there!

 

[FreshJR]

Lmao sorry y'all, but please read my original post!
I took the time to list everything I have already tried but everyone is suggesting me things I have already tried and listed there!

I did.

Disabling firewall and port forwarding are completely different things.

Disabling the firewall will not open ports.

 

[netwrks]

What mode is the Asus in? What mode is the Bell device in? Have you tried bypassing the Asus using the Bell device?

 

[Deleted member 58331]

I did.

Disabling firewall and port forwarding are completely different things.

Disabling the firewall will not open ports.

Oh sorry about that poor wording! I had tried both disabling the firewall, and enabling UDP/TCP 500 and 4500 unsucessfully

 

[Deleted member 58331]

What mode is the Asus in? What mode is the Bell device in? Have you tried bypassing the Asus using the Bell device?

I removed their equipment and plugged a TP-Link SFP to Ethernet, which is then directly connected to the ASUS router.

 

[pattiri]

Currently my AC88u lets wi-fi calling for my iphone x running with ios 11.3.

Regarding my previous experiences; sometimes it's works sometimes not and I have no idea what the problem is

 

[Deleted member 58331]

Hi all,

After extensive tests, I can confirm that neither my ISP or Merlin is the issue.
The issue is either with my actual router, or ASUSwrt.

When the router was removed and replaced by another one, Wi-Fi Calling worked properly.
A reset and flash to stock firmware of my RT-3100 did not work.

So... should I report the issue directly with ASUS?