engBoisvert, VArmstrong, SBaines, J T MBee, C PBiglietti, MBogaerts, ABosman, MBrandt, SCaron, BCasado, M PCataldi, GCavalli, DCervetto, MComune, GCorso-Radu, ADi Mattia, ADíaz-Gómez, MDos Anjos, ADrohan, JEllis, NickElsing, MEpp, BEtienne, FFalciano, SFarilla, AGeorge, SGhete, V MGonzález, SGrothe, MKaczmarska, AKarr, K MKhomich, AKonstantinidis, N PKrasny, WLi, WLowe, ALuminari, LMa, HMeessen, CMello, A GMerino, GMorettini, PMoyse, ENairz, ANegri, ANikitin, N VNisati, APadilla, CParodi, FPérez-Réale, VPinfold, J LPinto, PPolesello, GQian, ZRajagopalan, SResconi, SRosati, SScannicchio, D ASchiavi, CSchörner-Sadenius, TSegura, EDe Seixas, J MShears, T GSivoklokov, S YuSmizanska, MSoluk, R AStanescu, CTapprogge, StefanTouchard, FVercesi, VWatson, AWengler, TWerner, PWheeler, SWickens, F JWiedenmann, WWielers, MZobernig, GA New Implementation of the Region-of-Interest Strategy for the ATLAS Second Level TriggerDetectors and Experimental TechniquesATL-DAQ-2003-034Among the many challenges presented by the future ATLAS detector at the LHC are the high data taking rate and volume and the derivation of a rapid trigger decis ion with limited resources. To address this challenge within the ATLAS second le vel trigger system, a Region-of-Interest mechanism has been adopted which dramat ically reduces the relevant fiducial volume necessary to be readout and processe d to small regions guided by the hardware-based first level trigger. Software ha s been developed to allow fast translation between arbitrary geometric regions a nd identifiers of small collections of the event data. This facilitates on-deman d data retrieval and collection building. The system is optimized to minimize th e amount of data transferred and unnecessary building of complex objects. Detail s of the design and implementation are presented along with preliminary performance results.2003-06-11http://cds.cern.ch/record/685509DAQ and Triggerhttp://cds.cern.ch/record/685509oai:cds.cern.ch:685509