public DEREncodable getId() {
    if (id instanceof ASN1TaggedObject) {
      return ASN1OctetString.getInstance((ASN1TaggedObject) id, false);
    }

    return IssuerAndSerialNumber.getInstance(id);
  }
 public static SubjectKeyIdentifier getInstance(ASN1TaggedObject obj, boolean explicit) {
   return getInstance(ASN1OctetString.getInstance(obj, explicit));
 }