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I've built an application with integrated telephony that has users in Ireland, so we have an Irish call number in our communications service. So far, so good. The telephony works fine. However, the app is being extended to have users in Chicago too, so we bought and added a Chicago based number to the the comms service. Irish users will not be calling the US, nor vice versa. My query is this: for outgoing calls from the application, how does the comms service know which calling number to use? Must it be explicitly stated in the API request that initiates the call, or does it automatically figure it out based on the recipient number?
An Azure communication platform for deploying applications across devices and platforms.
Hi @Dylan Olney which Azure Communication Services API are you using for making calls (Calling SDK, Voice SDK)? Are you using direct calling or PSTN calling?
The outbound caller ID (the number shown to the recipient) needs to be explicitly specified in the API call. It doesn't automatically determine which number to use based on the recipient's location.
Thanks , I'm not 100% sure, but I think I'm using the voice calling SDK with PSTN calling. In the front-end of my app (React JS), I'm using the @azure/communication-calling library (npm), and the line of code below initiates an outgoing call:
const call = await CallAPI.callAgent.startCall([{ phoneNumber: <number to call> }], { alternateCallerId: { phoneNumber: <calling number> } });
As you can see, the startCall() function takes an alternateCallerId parameter where you may specify a calling number. The docs aren't really clear on this parameter though, so I thought it might be just for specifying a fallback number to use if the API isn't automatically able to determine which number to use based on the recipient's number. When we had just one number, I put that in there, but now that we have two, I guess it's just a case of deciding which one to use based on the caller's location. Thankfully, my app is able to differentiate between Irish and Chicago users. I just hope this parameter will be enough for it to know which calling number to use. Do you think it will?