Multipeer Connection issue with ipv6 don't get an invitation - ios

Question

My App was rejected by Apple because it can't connect to other device running iOS 10.1.1 on Wi-Fi connected to an IPv6 network.
When I tap on connect, the app continues to search for invitees and no further user action is produced.
I use Multi-peer Connectivity and I never tested my App being connected to an IPv6(It's my first release). But the App run very fine without having any connection or being connected to IPv4 network.
I don't know why the App is running and connecting fine using the IPv4 and doesn't connect to peer if the iPad is connected to an IPv6 network.
So my Question: Is it possible to use Multi-peer Connectivity with IPv6 so that Apple can approve the App or how should I handle this Issue ?
Here is my Code, maybe it is something wrong there.
#interface ConnectionManageriOS7 () <MCSessionDelegate, MCBrowserViewControllerDelegate>
{
UILocalNotification *_expireNotification;
UIBackgroundTaskIdentifier _taskId;
}
#property (nonatomic, strong) MCSession *session;
#property (nonatomic, strong) MCPeerID *localPeerID;
#property (nonatomic, strong) MCBrowserViewController *browserVC;
#property (nonatomic, strong) MCAdvertiserAssistant *advertiser;
#end
static ConnectionManageriOS7 *_manager = nil;
#implementation ConnectionManageriOS7
+ (ConnectionManageriOS7 *)connectManager {
#synchronized([ConnectionManageriOS7 class]){
if (_manager == nil) {
_manager = [[ConnectionManageriOS7 alloc] init];
}
return _manager;
}
return nil;
}
- (id)init {
self = [super init];
if (self) {
[self setupSessionAndAdvertiser];
}
return self;
}
- (void)setupSessionAndAdvertiser {
_localPeerID = [[MCPeerID alloc] initWithDisplayName:[UIDevice currentDevice].name];;
_session = [[MCSession alloc] initWithPeer:_localPeerID];
_session.delegate = self;
}
- (void)connectWithDelegate:(id)delegate {
_delegate = delegate;
if (_session.connectedPeers.count) {
if ([_delegate respondsToSelector:#selector(didConntectedWithManager:)]) {
[_delegate didConntectedWithManager:self];
}
} else {
if (_advertiser == nil) {
_advertiser = [[MCAdvertiserAssistant alloc] initWithServiceType:VISUS_Service
discoveryInfo:nil
session:_session];
_isConnected = NO;
[_advertiser start];
}
if (_browserVC == nil) {
_browserVC = [[MCBrowserViewController alloc] initWithServiceType:VISUS_Service session:_session];
_browserVC.delegate = self;
}
[(UIViewController *)delegate presentViewController:_browserVC
animated:YES completion:nil];
}
}
- (void)sendMessage:(NSString *)message {
NSData *textData = [message dataUsingEncoding:NSASCIIStringEncoding];
NSLog(#"Send Data: %#", message);
NSError *error = nil;
[_session sendData:textData
toPeers:_session.connectedPeers
withMode:MCSessionSendDataReliable
error:&error];
if (error) {
// 
[self session:_session peer:nil didChangeState:MCSessionStateNotConnected];
NSLog(#"error %#", error.userInfo);
}
}
- (void)stopService {
NSLog(#"Stop Service");
[_advertiser stop];
_advertiser = nil;
_browserVC = nil;
}
#pragma marks -
#pragma marks MCBrowserViewControllerDelegate
- (void) dismissBrowserVC{
[_browserVC dismissViewControllerAnimated:YES completion:nil];
}
// Notifies the delegate, when the user taps the done button
- (void)browserViewControllerDidFinish:(MCBrowserViewController *)browserViewController {
if ([_delegate respondsToSelector:#selector(didConntectedWithManager:)]) {
[_delegate didConntectedWithManager:self];
}
[self dismissBrowserVC];
}
// Notifies delegate that the user taps the cancel button.
- (void)browserViewControllerWasCancelled:(MCBrowserViewController *)browserViewController{
if (_browserVC == nil) {
[browserViewController dismissViewControllerAnimated:YES completion:nil];
}else {
[self dismissBrowserVC];
}
}
#pragma marks -
#pragma marks MCBrowserViewControllerDelegate
- (void)session:(MCSession *)session peer:(MCPeerID *)peerID didChangeState:(MCSessionState)state {
if (state != MCSessionStateConnecting) {
if (state == MCSessionStateConnected) {
_isConnected = true;
if ([_delegate respondsToSelector:#selector(willConntectedWithManager:)]) {
[_delegate willConntectedWithManager:self];
}
}
else {
_isConnected = false;
[self stopService];
if ([_delegate respondsToSelector:#selector(didDisconntectedWithManager:)]) {
[_delegate didDisconntectedWithManager:self];
}
}
}
}
// Received data from remote peer
- (void)session:(MCSession *)session didReceiveData:(NSData *)data fromPeer:(MCPeerID *)peerID{
// Decode data back to NSString
NSString *message = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
NSLog(#"Receive Data: %#", message);
// append message to text box:
dispatch_async(dispatch_get_main_queue(), ^{
if ([_delegate respondsToSelector:#selector(connectionManager:receivedString:)]) {
[_delegate connectionManager:self receivedString:message];
}
});
}
- (void)session:(MCSession *)session didFinishReceivingResourceWithName:(NSString *)resourceName fromPeer:(MCPeerID *)peerID atURL:(NSURL *)localURL withError:(NSError *)error {
_isConnected = false;
[self stopService];
NSLog(#"----- Error ----- %#", error.localizedDescription);
}
// Received a byte stream from remote peer
- (void)session:(MCSession *)session didReceiveStream:(NSInputStream *)stream withName:(NSString *)streamName fromPeer:(MCPeerID *)peerID {
}
// Start receiving a resource from remote peer
- (void)session:(MCSession *)session didStartReceivingResourceWithName:(NSString *)resourceName fromPeer:(MCPeerID *)peerID withProgress:(NSProgress *)progress {
}
- (void) session:(MCSession *)session didReceiveCertificate:(NSArray *)certificate fromPeer:(MCPeerID *)peerID certificateHandler:(void (^)(BOOL accept))certificateHandler
{
certificateHandler(YES);
}
- (void) createExpireNotification
{
[self killExpireNotification];
if (_session.connectedPeers.count != 0) // if peers connected, setup kill switch
{
NSTimeInterval gracePeriod = 20.0f;
// create notification that will get the user back into the app when the background process time is about to expire
NSTimeInterval msgTime = UIApplication.sharedApplication.backgroundTimeRemaining - gracePeriod;
UILocalNotification* n = [[UILocalNotification alloc] init];
_expireNotification = n;
_expireNotification.fireDate = [NSDate dateWithTimeIntervalSinceNow:msgTime];
_expireNotification.alertBody = #"Bluetooth Connectivity is about to disconnect. Open the app to resume Test";
_expireNotification.soundName = UILocalNotificationDefaultSoundName;
_expireNotification.applicationIconBadgeNumber = 1;
[UIApplication.sharedApplication scheduleLocalNotification:_expireNotification];
}
}
- (void) killExpireNotification
{
if (_expireNotification != nil)
{
[UIApplication.sharedApplication cancelLocalNotification:_expireNotification];
_expireNotification = nil;
}
}
- (void)bacgroundHandling {
_taskId = [[UIApplication sharedApplication] beginBackgroundTaskWithExpirationHandler:^
{
[self stopService];
[[UIApplication sharedApplication] endBackgroundTask:_taskId];
_taskId = UIBackgroundTaskInvalid;
}];
[self createExpireNotification];
}
- (void)advertiser:(MCNearbyServiceAdvertiser *)advertiser didReceiveInvitationFromPeer:(MCPeerID *)peerID withContext:(NSData *)context invitationHandler:(void(^)(BOOL accept, MCSession *session))invitationHandler
{
// http://down.vcnc.co.kr/WWDC_2013/Video/708.pdf -- wwdc tutorial, this part is towards the end (p119)
// self.arrayInvitationHandler = [NSArray arrayWithObject:[invitationHandler copy]];
// ask the user
UIAlertView *alertView = [[UIAlertView alloc]
initWithTitle:peerID.displayName
message:#"Would like to create a session with you"
delegate:self
cancelButtonTitle:#"Decline" otherButtonTitles:#"Accept", nil];
[alertView show];
}
- (void) alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex
{
// retrieve the invitationHandler and check whether the user accepted or declined the invitation...
BOOL accept = (buttonIndex != alertView.cancelButtonIndex) ? YES : NO;
// respond
if(accept) {
// void (^invitationHandler)(BOOL, MCSession *) = [self.arrayInvitationHandler objectAtIndex:0];
// invitationHandler(accept, self.mySession);
}
else
{
NSLog(#"Session disallowed");
}
}
- (void)terminate {
[self killExpireNotification];
[self stopService];
}
#end

Answer 1

I have solved the problem. For everybody with simular problem:
It wasn't a problem with IPv6, it is a matter of how to use Multipeer connectivity. In my Case I tryied to the the IPv6 connection with a iPad and a Simulator. And I used my Macbook for creating a nat64 network. And the reason why the simulator and iPad never saw each other the fact that they where not connected to same wifi network.
Solution:
Just take for testing two iPads and use your mac as nat64 network accesspoint.