Apple

I am working on development of accessory that uses the Authentication Processor 2.0C.
During the authentication of the accessory by the device (iPhone5), I see the following sequence of operation with a sniffer:

1. GetAccessoryAuthenticationInfo' (0x14) Device to Accessory
2. ReturnAccessoryAuthenticationInfo (0x15)
3. iPodAck (0x02)
4. ReturnAccessoryAuthenticationInfo (0x15) .... this goes no until i get an
5. 'AckAccessoryAuthenticationInfo' (0x16) with a 'Success' status.
6. Subsequently, I can see the 'GetAccessoryAuthenticationSignature' (0x17) being sent by the iPhone5.
7. The accessory is responding with 'RetAccessoryAuthenticationSignature' (0x18).

After this the iPhone5 does not send the 'AckAccessoryAuthenticationStatus' (0x19) message. Neither with success or failure.
The iPhone then waits for 75 seconds and (re)starts the whole authentication process beginning with 'GetAccessoryAuthenticationInfo' (0x14).
Sometimes the iPhone goes through the whole authentication process (steps 1 to 7) two times and sometimes it goes through the process 3 times before disconnecting the device.
But during every authentication attempt the iPhone does not send the 'AckAccessoryAuthenticationStatus' (0x19) message.

I checked the timings between the 'GetAccessoryAuthenticationSignature' (0x17) being sent by the iPhone5 and the 'RetAccessoryAuthenticationSignature' (0x18) response from the accessory. It is less than one second which is within the IAP specification of 2 seconds.

I tried replacing the iPhone with the iPad and that too shows the same behavior.

Any insight in understanding the circumstances under which the iPhone will not send the 'AckAccessoryAuthenticationStatus' message will be of great help.

Also, are there any tools available that will allow me to log the events on the iPhone to track the problem?

Thanks in advance
Subodh