Unable to send iOS MDM Push Notification using Push Sharp - ios

Question

I am attempting to send the an MDM push notification to an iPad using the production APN server. However, Push Sharp says that the notification failed because the identifier is equal to 1. The following code from the PushSharp code base illustrates how it comes to that conclusion...
//We now expect apple to close the connection on us anyway, so let's try and close things
// up here as well to get a head start
//Hopefully this way we have less messages written to the stream that we have to requeue
try { stream.Close(); stream.Dispose(); }
catch { }
//Get the enhanced format response
// byte 0 is always '1', byte 1 is the status, bytes 2,3,4,5 are the identifier of the notification
var identifier = IPAddress.NetworkToHostOrder(BitConverter.ToInt32(readBuffer, 2));
int failedNotificationIndex = -1;
SentNotification failedNotification = null;
//Try and find the failed notification in our sent list
for (int i = 0; i < sentNotifications.Count; i++)
{
var n = sentNotifications[i];
if (n.Identifier.Equals(identifier))
{
failedNotificationIndex = i;
failedNotification = n;
break;
}
}
Basically, after the writing the payload to the stream, it attempts to close the connection, during which it expects a response from the APN service, which I think it refers to as the notification identifier.
I have plugged the device into the iPhone Device Configuration utility, but nothing appears in the console, hence I assume that it never receives this notification.
My questions are...
What is this identifier that it is expecting ?
Is there anything that I am doing wrong ?
The device is running iOS 6. The structure of the payload is as follows...
{"aps":{},"mdm":"80369651-5802-40A2-A0AE-FCCF02F99589"}
The values in the returned byte[] of 6 bytes are as follows 8,8,0,0,0,1

Answer 1

No idea, I've never looked into the details how PushSharp deals with the APNS internals.
You shouldn't send the "aps":{} part in the notification payload, so maybe that's the reason the APNS fails the notification.
I'm sucessfully using PushSharp 1.0.17 with the following code for MDM notifications, so it definitely works in general.
var pushService = new PushService();
// attach event listeners
// override the production/development auto-detection as it doesn't
// work for MDM certificates
var cert = null; // load your push client certificate
var channel = new ApplePushChannelSettings(true, cert, true);
pushService.StartApplePushService(channel);
// create and send the notification
var notification = NotificationFactory
.Apple()
.ForDeviceToken("your-device-token-received-from-checkin")
.WithExpiry(DateTime.UtcNow.AddDays(1))
.WithCustomItem("mdm", "your-push-magic-received-in-checkin");
pushService.QueueNotification(notification);

Answer 2

For PushSharp v3.0+, you should be able to include directly in the Payload of the ApnsNotification.
public void SendIosMdm(string deviceToken, string pushMagic)
{
_apnsBroker.QueueNotification(new ApnsNotification
{
DeviceToken = deviceToken,
Payload = JObject.FromObject(new {
mdm = pushMagic
})
});
}