A method and apparatus constructs a preferred certificate chain, such as a
list of all certificate authorities in a shortest trusted path, based on
generated certificate chain data, such as a table of trust relationships
among certificate issuing units in a community of interest, to facilitate
rapid validity determination of the certificate by a requesting unit. In
one embodiment, requesting units, such as certificate validation units or
subscribers, send queries to a common certificate chain constructing unit.
Each query may identify a beginning and target certification authority in
the community. The certificate chain constructing unit then automatically
determines the certification chain among certification issuing units
between the beginning and target certification authorities for each query
and provides certificate chain data to the requesting unit. The requesting
unit then performs validity determination on the certificate to be
validated based on the certificate chain data.