how to restrict mobile app access to only wifi

In enterprise application , the need for apps to use only wifi comes to picture sometimes as they can access intranet through wifi.

But with the advent of wifi-assist.It's possible sometimes Mobile data will be used for internet connectivity simultaneously along with wifi.

so how to stop this from happening so that app can use only wifi not mobile data.

allowscellularaccess property of NSMutableURLRequest solves the issue.

so if set this value to NO then if there is no wifi then it'll ignore the mobile data and return internet connect offline error message

Here is sample code to test

    NSMutableURLRequest *request=[[NSMutableURLRequest alloc]initWithURL:[NSURL URLWithString:@"https://www.google.com"]];    [request setAllowsCellularAccess:NO];    NSError *error;
        NSURLSessionConfiguration *configuration = [NSURLSessionConfiguration defaultSessionConfiguration];    NSURLSession *session = [NSURLSession sessionWithConfiguration:configuration delegate:self delegateQueue:nil];        [request setHTTPMethod:@"GET"];
        NSURLSessionDataTask *postDataTask = [session dataTaskWithRequest:request completionHandler:^(NSData *data, NSURLResponse *response, NSError *error) {
        NSLog(@"error:%@",error);
        NSLog(@"success:%@",response);
    }];
        [postDataTask resume];

Here is the sample error message we get

Error Domain=NSURLErrorDomain Code=-1009 "The Internet connection appears to be offline." UserInfo={NSUnderlyingError=0x1c004b700 {Error Domain=kCFErrorDomainCFNetwork Code=-1009 "(null)" UserInfo={_kCFStreamErrorCodeKey=50, _kCFStreamErrorDomainKey=1}}, NSErrorFailingURLStringKey=https://www.google.com/, NSErrorFailingURLKey=https://www.google.com/, _kCFStreamErrorDomainKey=1, _kCFStreamErrorCodeKey=50, NSLocalizedDescription=The Internet connection appears to be offline.}

Multipath tcp in iOS

Multipath TCP enables iOS to use both wifi and data connection simultaneously which increases the user experience and works around common problem network latency,network connection drop out,etc.

It was introduced in iOS 7 itself and it was used by only Siri but it is released for developers.
since iOS 11.

This can be lot more useful when it comes to streaming of audio and video.

One can opt multipath tcp in NSURLSession

var multipathserviceType:URLSessionConfiguration.MultipathServiceType
none =0
handover = 1
interactive=2

None:

It never used multipath acts as usual

Handover:

acts more like how wifi assit works i.e only when wifi is weak it uses data and if wifi signal gets stronger then it uses wifi

Interactive:

It uses both wifi and data at a same time but it will not be very aggressive on data network.
Siri uses interactive mode

Aggregate:

Same as interactive but it'll use data network aggressively