The Air Data System get its information through 10 external sensors installed in the plane fuselage skin: 3 Pitot tubes (or probes) to get the Total Air Pressure (static plus dynamic), 6 Static Ports (to get air static pressure only) and 1 Outside Air Temperature (OAT) sensor. The Pitot probes and Static ports are connected to several Air Data Computers (ADC) as this diagram shows:

NOTE: I think there's an error in the labelling. From this diagram you get that the plane has only 3 Static ports: 1 (Captain), 2 (Copilot) and 3 (Standby). I think all sensors on the left should have been labelled as Captain and all sensors on the right should have been labelled as Copilot. In this way there are 1 Pitot probe + 2 Static ports in the port side of the plane's skin, 1 Pitot probe + 2 Static ports in her starboard side plus a Pitot probe and a Static port in the port side (both Standby) and a Static port in the starboard side (Standby too). The OAT sensor is not shown.

Abbreviations:

ADM: Air Data Module. It's a specialised transducer that converts pressure values to electric current.

ADIRU: Air Data Inertial Reference Unit. From the electrical inputs of the ADM's plus the Inertial Reference got from the aircraft INS (Inertial Navigation System) calculates all Air Data referred previously plus the wind vector in each moment

ISIS: Integrated Standby Instruments System. Gets its air data information directly by a pneumatic way from the standby sensors, Pitot probe 3, Static port 3 (captain) and Static port 3 (copilot)...