  Parking spaces are resources that can be pooled together and shared,
especially when there are complementary day-time and night-time users. We
answer two design questions. First, given a quality of service requirement, how
many spaces should be set aside as contingency during day-time for night-time
users? Next, how can we replace the first-come-first-served access method by
one that aims at optimal efficiency while keeping user preferences private?
