The connectivity performance offered from an airport (airport connectivity) is made up of all connections offered from the airport either direct or indirect via an intermediate hub. Hubconnectivity represents the connectivity offered via (with a transfer at) the airport.

Traditionally, connectivity is represented by the number of destinations or the number of direct flights offered from an airport. Although valuable in itself, this does not provide insight into the indirect and hub connectivity provided by the airports. The SEO NetScan connectivity model follows a more comprehensive approach and takes all three types of connectivity into account.

The NetScan model first identifies all direct and indirect (one-stop) connections available on an airport-pair. The model uses OAG passenger flight schedule data on direct flights as input. The flight schedules for the third week of June are used. Indirect connections are created within the model by connecting two direct flights taking into account minimum and maximum connecting times. Indirect connections are possible at any given airport between:

• flights of the same airline;
• flights of airlines working together in an alliance or through a codeshare agreement. The alliance and codeshare compositions are specified for the specific year of analysis.

As indirect connections are less attractive to the passenger than direct connections, due to the transfer and circuity time involved, each connection is weighted for its quality. The quality of a connection ranges between zero and one. A direct, non-stop flight operated by a jet aircraft is given the maximum quality of one. The quality of an indirect connection will always be lower than one since travel time is added due to transfer time and circuity time. The same holds true for a direct multi-stop connection or a direct connection operated by a turboprop: passengers face a lower network quality because of a longer travel time. Connections with a too long travel time relative to the theoretical direct flight time will be assigned a quality of 0. As such, these connections are considered to be unrealistic travel options for the passenger.
 
Summing the quality adjusted connectivity values offered by an airport on a certain airport-pair gives the total connectivity on the airport-pair. Summing direct and indirect connectivity offered from an airport yields the airport connectivity, which measures the connectivity available to passengers departing from the airport. Adding up hubconnectivity by transfer (hub) airport yields the connectivity offered via the airport, which gives an indication of the performance of an airport as a transfer point.

Since 1997, NetScan has been applied in many consultancy studies for different stakeholders and has been widely published in the international peer-reviewed academic journals.