  Abadi has introduced a logic to explicate the meaning of local names in SDSI,
the Simple Distributed Security Infrastructure proposed by Rivest and Lampson.
Abadi's logic does not correspond precisely to SDSI, however; it draws
conclusions about local names that do not follow from SDSI's name resolution
algorithm. Moreover, its semantics is somewhat unintuitive. This paper presents
the Logic of Local Name Containment, which does not suffer from these
deficiencies. It has a clear semantics and provides a tight characterization of
SDSI name resolution. The semantics is shown to be closely related to that of
logic programs, leading to an approach to the efficient implementation of
queries concerning local names. A complete axiomatization of the logic is also
provided.
