The Functional Design show the functionality of the Pet system.
This is the states that a pet can be in.
When dismissed the pet will be in a state where if resummoned the time lived will not be reset. After the DismissedLockoutTime the time lived is reset to 0. This penalty has to be taken either before logout or before summoning after login.
In the Physical Design the different parts of the functional design is allocated to different systems. Some are handled server side, other at the npcclient. Some in code and others in scripts.