GDS is:
Global Distribution System and it is a
computer reservations system CRS that provides access for
airlines,
car hire groups and
hotel chains. The GDS provides information for
travel agents on
fares,
availablity,
schedules and general travel
industry related features including visa and passport requirements. All seating, meal and special requests are dealt with through a GDS. Some systems have evolved from programmes designed for army matters, but in general it is a system designed and used by travel corporations pre internet bookings.
Various airlines use different systems. The main servers are WORLDSPAN, Amadeus, Sabre and Galileo. Although quite interesting names the systems are in fact visually bland and consist of short hand codes instead of internet based programmes that give instant information a GDS requires training and patience as each system has a different entry.
All flights are booked into the system under a PNR a passenger name record and for correspondance with an airline regarding a flight for each reservation there is a RL a record locator. The airline will not see your travel agency's PNR so you have to find the RL in order to conduct inquiries.
So although it is easy to book a flight online the actual data you enter into neat databases is then translated by the booking engine, which in the majority of cases is Corre, into GDS entries. These entries are then deciphered out of trade jargon into consumer friendly titbits. Through a series of Queues within the GDS an airline can communicate with the booking/travel agent about changes to a passengers flight. Users of the GDS have to access the Q's and translate the code in order to see if an airline has granted a schedule change or meal request for a passenger.
Then this gobbleygook is magically transported into a consise language and sent to the passenger usually via email. The whole process is universal, efficient and clear cut EXCEPT when an entry cannot be understood and it takes ages to work it out and involves calling airlines numerous times in order to work out what the hell it means! The GDS is also a great way to log out of your annoying telephone and waste half an hour...all legit as well! Call centre victims of the world unite!