For air traffic control, SASS-C is an acronym for "Surveillance Analysis Support System for ATC-Centre". SASS-C Service is part of Eurocontrol Communications, navigation and surveillance. Introduction SASS-C Service provides two main software suites: VERIFication: ATC surveillance infrastructure assessment. PREDICTion: performance theoretical calculation of the ATC surveillance sensors. VERIFication Usage There are two key functions of SASS-C VERIFication: evaluation of the actual performance of ATC sensors or infrastructure against different standard like Eurocontrol Specification for ATM Surveillance System Performance (ESASSP). incident investigation. SASS-C VERIFication is designed to handle all current surveillance technologies (PSR, SSR, Mode-S, ADS-B, WAM) as well as trackers. Evolutions for handling drones, Multi Static Primary Surveillance (MSPSR) and Surface Movement Area-specific sensors are considered in the future. Modules SASS-C VERIFication is divided into many modules. The key ones are: IRIS: ATC surveillance data recording, decoding and statistics. In supports many framing or coding surveillance data format. One between many: ASTERIX. OTR (Opportunity Traffic Reconstructor): build a reference trajectory based on the ATC surveillance data generated by the opportunity traffic. This module is widely inspired by the real-time tracker technologies like Kalman filter. But it takes also advantage that it works off-line: the aircraft trajectories are known over the complete dataset time window. CMP (Comparator evaluation suite): it is the hearth of VERIFication. The CMP module compares the ATC surveillance data against reference that can be generated by OTR or imported from external source. It generates performance indicators (e.g. detection probability, accuracy) suitable for assessment against standards like ESASSP. REPORT: configurable reporting and trend analysis. DISPlay: this module displays ATC surveillance data, reconstructed data and performance indicators on different supports like geographical view, scatter diagram, table or mosaic. History Since the beginning of development in 1988 based on MURATREC (1985), the SASS-C software has been under constant evolution to cope with supplementary user requirements, to cover surveillance technology upgrades and to follow software technology changes. SASS-C v6 In version 6, both suites where included in a common package just named SASS-C. This early version was supporting only PSR/SSR/Mode-S Radars and trackers. VERIFication v7 Since end of 2003 and in order to prepare SASS-C for the next decade, important software re-engineering has been undertaken in conjunction with functional upgrades, with the aim to introduce up to date technologies in all relevant fields while enhancing system quality. The main functional upgrades relate to the introduction of Aircraft Derived data (Mode S