SIP Client app - Push notification unavailable

Hello Team,

We have developed an SIP Client application, where the connection is through SIP Server.

  1. We are unable to handle incoming calls when app is in the background. The local servers are blocked by firewall due to which the push notification is unavailable and is only available via VPN connection. Requesting you to please guide us on how we can receive incoming calls without push notification.
  2. We also would like to know how we can receive incoming calls when the app is completely terminated or closed from background and how to auto-start the app to receive incoming calls.

Replies

Hi,

Other than PushKit, the only voip API option available is the Local Push Connectivity Extension.

That API uses an App Extension to maintain a network connection to your call server, allowing you to replicate the same general behavior as PushKit on isolated network. Note that it will only function on specific Wifi networks your app configures, not Wifi in general. This approach also handles #2 in the same way PushKit does.

One other note on t this statement:

"...where the connection is through SIP Server."

From past experience, many developers start voip app design with the assumption that the SIP server's implementation cannot be modified, so the client will have to adapt to it's design. In my experience, that simply doesn't work. Like most background categories, the "voip" category defines exactly how apps are expected to behave and your app will need to fit within those requirements. That may very well mean that you can't make a voip apps that works with your current server, in which case you may very well need to change your servers implementation.

-Kevin Elliott
DTS Engineer, CoreOS/Hardware

Hi Kevin,

Thanks for your solution.