PKIX1 { }
DEFINITIONS IMPLICIT TAGS ::=
BEGIN
id-ce OBJECT IDENTIFIER  ::=  {joint-iso-ccitt(2) ds(5) 29}
id-ce-authorityKeyIdentifier OBJECT IDENTIFIER ::=  { id-Ce 35 }
AuthorityKeyIdentifier ::= SEQUENCE {
      keyIdentifier             [0] KeyIdentifier            OPTIONAL,
      authorityCertIssuer       [1] GeneralNames             OPTIONAL  ,
    authorityCertSerialNumber [2] CertificateSerialNumber  OPTIONAL }
    -- authensions OPTIONAL }
RevokedInfo ::= SEQUENCE {
    revocationTime       n OPTIONAL }
UnknownInfo ::= NULL -- this can be replaced with an enumeration
END