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# CTRadioAccessTechnologyDidChangeNotification

The name of the notification indicating that the radio access technology changed for one of the services.

```
extern NSString * const CTRadioAccessTechnologyDidChangeNotification;
```

## Discussion

The notification’s <doc://com.apple.documentation/documentation/Foundation/NSNotification/object> is an <doc://com.apple.documentation/documentation/Foundation/NSString> that represents the service identifier of the service whose radio access technology has changed. Use this string as the key in [`serviceCurrentRadioAccessTechnology`](/documentation/CoreTelephony/CTTelephonyNetworkInfo/serviceCurrentRadioAccessTechnology) to get the value of the new radio access technology for the service.

---

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