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There are identifiers that are used on different request/response chains.

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13.1.1. EXCURSIONRESERVATIONIDS

The ExcursionReservationIDs is used as unique identifier of a booking.

The next values of ResID_Source attribute defines three possible types of HotelReservationID ExcursionReservationID element:

"client". It is mandatory identifier required in all requests/responses. It can be any character string, but it must be unique in your system. This element allows GP Travel HUB to identify your booking within it.

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"supplier". Each actual reservation returns "supplier" identifier - the unique identifier of the booking in supplier's system. Normally this value should be further used in hotel voucher.  ResID_SourceContext attribute identifies the supplier. It is not necessary to pass the "supplier" identifier in all following requests; only "client" is required.

You have to store all values of HotelReservationIDs ExcursionReservationIDs in your system, and use it unchanged through whole booking's life cycle.

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Diagram 1113.1.1.1. ExcursionReservationIDs flow

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<ExcursionReservationIDs>
  <ExcursionReservationID ResID_Source="agent" ResID_Value="hjo8dfg"/>
  <ExcursionReservationID ResID_Source="client" ResID_Value="34rf4g3frre45"/>
  <ExcursionReservationID ResID_Source="supplier" ResID_SourceContext="supplierCode" ResID_Value="164-4732160"/>
</ExcursionReservationIDs>

13.1.2. BOOKINGCODE

The BookingCode attribute in ExcursionRate element is used as unique identifier of an offer starting Excursion Availability response and till the time the booking is confirmed. The BookingCode is valid for limited time (normally 15 minutes); if the reservation was not confirmed (or at least initiated) during this time limit, then new search should be performed again.

As the unique offer identifier, BookingCode should also be used in Excursion Charges and Excursion Descriptive Info requests.

BookingCode may change between Availability search and Reservation Initiate response (it depends on supplier specific). In Reservation Confirmation request, the BookingCode must be taken from the Reservation Initiate response.

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Diagram 13.1.2.1. BookingCode usage

Since an excursion booked, the BookingCode does not play role for the reservation anymore. The ExcursionReservationIDs should be used for the booking cancellation.

13.1.3. TRANSACTIONIDENTIFIER

Excursion Reservation and Cancellation should always be done in two steps: 1) Initiation (request/response) and 2)Confirmation or Ignore (request/response). Both these steps have to be done within one transaction.

The TransactionIdentifier allows to recognize which Confirmation or Ignore request relates to the Initiation response.

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Diagram 13.1.3.1. TransactionIdentifier usage