Each request to GP Travel HUB has to identify particular booking to be processed. For that purpose special unique identifiers are used.

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"supplier". Each actual reservation returns "supplier" identifier - the unique identifier of the booking in supplier's system. ID_Context attribute identifies the supplier. It is not necessary to pass the "supplier" identifier in all following requests; only "client" is required. But in response it is mandatory (is it correct?).

"PNR". It is an optional reference needed for online check-in. It can be presented by several references depending on airlines quantity.

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Diagram 24.1.1.1.BookingReferenceID flow

24.1.3. TRANSACTIONIDENTIFIER

Flight Reservation, Modification 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 24.1.3.1. TransactionIdentifier usage