João Porto de Albuquerque Heiko Krumm Paulo Lício de Geus On Scalability and Modularisation in the Modelling of Network Security Systems. 287-304 2005 conf/esorics/2005 ESORICS http://dx.doi.org/10.1007/11555827_17 db/conf/esorics/esorics2005.html#AlbuquerqueKG05