def encode
            elems = []
            elems << OpenSSL::ASN1::ASN1Data.new([encode_pvno], 0, :CONTEXT_SPECIFIC)
            elems << OpenSSL::ASN1::ASN1Data.new([encode_msg_type], 1, :CONTEXT_SPECIFIC)
            elems << OpenSSL::ASN1::ASN1Data.new([encode_tickets], 2, :CONTEXT_SPECIFIC)