3CX on 3G/4G

[SVanBC]

Hi

As our customer keeps complaining about not receiving his phone calls on his iPhone, I start to wonder how reliable the 3CX client is on the 3G/4G network.

Apperently when our client moves off-site and connects to the 3G/4G network, his calls will not always connect to his iPhone and not receive any PUSH notification; although 3CX is allowed to use his mobile data on his iPhone.

Made a call to our license distributor and he told us that 3CX is not the product to offer as an off-site VOIP solution due to (possibly) bad 3G/4G coverage in the area. When I test the 3G network at the client side, I can browse and stream YouTube with no issues. But why is the 3CX only receiving PUSH notifications from time to time and not 24/7? Dynamic IP issue? Port issue? 3G/4G issue?

Not sure if anyone else has this specific issue; where he is using 3CX completly on his mobile device and whether or not he is missing some incoming calls? Is this normal behavior that not every call will connect to the iPhone?

If anyone has any experience with this, i'd love to hear it

Regards,

Sven

 

[Vali_3CX]

Hi Sven

If he receives the "missed call" notification, that means there is no problem with the push "transmission channel".

For a push call, there is a different story:
- First of all, if he has on his extension several mobile devices (Android/iOS) configured for push, then these devices will "steal" the push from each other: only the last registered device will receive the push call.
- Second, the push call is shown as call ONLY when the client is properly SIP registered to the PBX, therefore only when user is able to answer it. As an extreme case as example, if client's SIP password is wrong, then the call will not be shown, even the push payload has been received, because SIP registration failed in the background.

 

[SVanBC]

I'm seeing many register/unregister events in the event log on the PBX. These are coming from the 2 extensions that are loaded on the iPhone.

Not a single extension is used twice. 3 Users have their own extension: User 1 has Extension 1 on his iPhone, User 2 has extension 2 on his iPhone and User 3 has her extension on a SNOM320 (with no issues at all).

The iPhones occasionally receive a PUSH notification, not always, usually not when on the 3G/4G network.

 

[Vali_3CX]

Push (as a signal, message, payload, whatever name it) once sent is never lost. So, either PBX has a reason to don't send it (for instance, device is registered), either send it to a different device (as described above) or the device which receive it has a reason to don't show the call (again, as described above).

Also, there might be a client-related reason which prevents the PBX to send push: device's network changing: client registers to the PBX as coming from WiFi; now, if client's device switch in the background to 3G or a different WiFi, for max 2 minutes (registration timeout) it will not receive push, since it still appear as registered on the PBX.

 

[AWS2P]

Hi, i have same problem, lots of register/unregister events in log sometimes in 1 second, I have only one Iphone 6 on the PBX , no other 3G phones.
Iphone is not seen in phones item in console but visible in extensions.

 

[SVanBC]

I see, that explains the register/unregister events in the log. In about 1min and few seconds the unregistered extension, registers again. First it registers as 127.0.0.1 and then it unregisters as 127.0.0.1, registers as 10.10.80.x and unregisters as 10.10.80.x ...


As far as I know, our client is using it on WiFi and cellular (both enabled at the same time).

Is there any workaround to get this 3CX iOS issue resolved?

 

[eddv123]

I find that very odd that your 3CX Distributor is actively not promoting the use of the 3CX Client - not good!

I have had known of similar issues with customers myself however it is always normally related to the network that either 3CX is running on (non RFC Complaint internal subnet) or the 3/4G signal wireless that the client is currently running.

 

[Vali_3CX]

Svan, no, there is no workaround, it would involve mainly the PBX (specifically the dialer) to be modified. The main reason of the current implementation is to avoid complications generated by two "incoming call" notifications (one SIP and one PUSH) being sent to the client for the same call; not only the client should be able to distinguish that the second notification is for a call which it already answered, but also there is not a new call coming from the same caller - things like this.

 

[AWS2P]

Is this kind of situation you have ?

 

[SVanBC]

View attachment 6894
Is this kind of situation you have ?

Exactly my issue!

 

[SVanBC]

I find that very odd that your 3CX Distributor is actively not promoting the use of the 3CX Client - not good!

I have had known of similar issues with customers myself however it is always normally related to the network that either 3CX is running on (non RFC Complaint internal subnet) or the 3/4G signal wireless that the client is currently running.

Sorry,he does recommend the product but told us that poor 3G/4G coverage (or driving in the car) may cause problems with connectivity to the client on the iPhone. Therefor it's not the best way if you want to be available 24/7 whilest off site.

 

[SVanBC]

Svan, no, there is no workaround, it would involve mainly the PBX (specifically the dialer) to be modified. The main reason of the current implementation is to avoid complications generated by two "incoming call" notifications (one SIP and one PUSH) being sent to the client for the same call; not only the client should be able to distinguish that the second notification is for a call which it already answered, but also there is not a new call coming from the same caller - things like this.

Hmm.. I'm a little confused but I think I understand.

Too bad we can't offer the product as a solution for clients that are active on multiple locations with only 3G/4G connectivity. (construction workers, ...)

 

[eddv123]

Hi SVanBC,

But when have you ever known any mobile device to be reliable 100% of the time ? unless it is a military grade SAT phone or something like that Even your GSM mobile experiences blind spots if you are in an area with poor coverage.

As a distributor of the product where I am happy they have been realistic they should not disregard the 3CX Client as it is a good bit of software which I have found it works better than most of the big "brand" name PBX offerings out on the market.

 

[SVanBC]

Hi Eddv,

You are completely right and I understand.

I love 3CX, seriously, but our client wants to receive his calls on his iPhone 24/7 and not 50% chance when using 3G/4G. I myself am pretty new to the product and that brings me here, at the forums, looking for possible solutions

 

[Vali_3CX]

Svan, to make it clear: the problem doesn't occur when the device is on a stable network (doesn't matter is WiFi or 3G); it occurs for max 2 mins when switching networks. Therefore, if you're in a car and your device is on 3G it will work.

 

[SVanBC]

Svan, to make it clear: the problem doesn't occur when the device is on a stable network (doesn't matter is WiFi or 3G); it occurs for max 2 mins when switching networks. Therefore, if you're in a car and your device is on 3G it will work.

Thanks. I will advice my client to make sure he uses WiFi on site and turns it off as he leaves, so his WiFi won't connect to other known SSIDS in the area and retriggering the 2 minut timer so his 3G takes over for the rest of the day (off site).

 

[mtech1]

We have had success by setting 3cx client to login on WiFi only and then use twin or forwarding when on cellular

 

[SVanBC]

I'm sorry but wat do you exactly mean with 'twin'? Did you configure these settings on the extension itself?

 

[jbryant84]

I stopped recommending the client a long while ago. The client is very good at acting like its registered when it isn't. You can have the client open, it shows on hook, and do a test call to the extension, straight to vmail. Hopping from lte/wi-fi kills it, and it doesn't successfully reregister. I tell customers to turn it on to make an outbound call (mask callerid) but turn it right back off, and instead use forwarding rules (typically away status button on desk phone that forwards calls to mobile number). They don't like losing the ability to transfer calls, but like calls going straight to voicemail because of a broken client even less.

 

[accentlogic]

We have found most of the issues occur when driving. 3G/4G is great for streaming audio or video, where it can buffer a few seconds - but not so much for VoIP.

We counsel users to configure calls to Forward to Mobile when they are out, and if they are driving down the freeway to ignore the 3CX push notice and let the call roll to the cell. Not an option for all, but it helps.

The "twin" feature @mtech1 mentioned is the "Ring my mobile simultaneously" under the extension forwarding rules for some of the Status options. If the user does not/cannot use the app this can be useful, but if they have the 3CX mobile app it would not make sense to do both at the same time.