You can investigate protocols on paper, using the Microsoft "Open Specifications" available on the MSDN web site.
Activesync is documented - see the Microsoft specification information.
Some early (from before the documentation was released) investigations are documented in Activesync investigation.
Automatic service discovery¶
The mailbox discovery information is document in [MS-OXDISCO] and [MS-OXDSCLI]. Our investigation is documented in Autodiscover investigation.