Go through Reachability class by Apple. It has all the functions you need. Your best bet here is to use a domain (like Google) to check for actual internet connectivity.
Summarised sample code:
Add observer in didFinishLaunchingWithOptions:
[[NSNotificationCenter defaultCenter] addObserver:self
selector:@selector(checkNetworkStatus:)
name:kReachabilityChangedNotification
object:nil];
internetReachable = [[Reachability reachabilityForInternetConnection] retain];
[internetReachable startNotifier];
// check if a pathway to a random host exists
hostReachable = [Reachability reachabilityWithHostname:@"SOME_HOST"];
[hostReachable startNotifier];
Then, in the target method:
- (void) checkNetworkStatus:(NSNotification *)notice {
NetworkStatus internetStatus = [internetReachable currentReachabilityStatus];
switch (internetStatus)
{
case NotReachable:
{
NSLog(@"The internet is down.");
break;
}
case ReachableViaWiFi:
{
NSLog(@"The internet is working via WIFI.");
break;
}
case ReachableViaWWAN:
{
NSLog(@"The internet is working via WWAN.");
break;
}
}
NetworkStatus hostStatus = [hostReachable currentReachabilityStatus];
switch (hostStatus)
{
case NotReachable:
{
NSLog(@"A gateway to the host server is down.");
break;
}
case ReachableViaWiFi:
{
NSLog(@"A gateway to the host server is working via WIFI.");
break;
}
case ReachableViaWWAN:
{
NSLog(@"A gateway to the host server is working via WWAN.");
break;
}
}
}