1 3 AN IATA Airport or IATA City Code. For test-bed nodes, provider specific code. 2 1 AN Provider code : - A ARINC - B IBS - C Ink Aviation - D BagDrop Systems - E Edge Airport - I AirIT - K IIAC and Asiana IDT - R RESA - S SITA - T Travelsky - U Ultra 3 1 AN If testbed node, set to \Z", otherwise use any character except for \Z". 4 7 AN Additional free-form characters. Provider- and/or installation specific. 5* 2 AN Device type code from Table 2.3 on page 12 6* 1 N Device Index. Provider- and/or installation specific.