Robust Software Engineering

Rlblty ngnrng s sb-dscpln f systms ngnrng tht mphszs th blty f qpmnt t fnctn wtht flr. Rlblty s dfnd s th prbblty tht prdct, systm, r srvc wll prfrm ts ntndd fnctn dqtly fr spcfd prd f tm, R wll prt n dfnd nvrnmnt wtht flr. Rlblty s clsly rltd t vlblty, whch s typclly dscrbd s th blty f cmpnnt r systm t fnctn t spcfd mmnt r ntrvl f tm. Th rlblty fnctn s thrtclly dfnd s th prbblty f sccss. n prctc, t s clcltd sng dffrnt tchnqs, nd ts vl rngs btwn 0 nd 1, whr 0 ndcts n prbblty f sccss whl 1 ndcts dfnt sccss. Ths prbblty s stmtd frm dtld (physcs f flr) nlyss, prvs dt sts, r thrgh rlblty tstng nd rlblty mdlng. vlblty, tstblty, mntnblty, nd mntnnc r ftn dfnd s prt f "rlblty ngnrng" n rlblty prgrms. Rlblty ftn plys ky rl n th cst-ffctvnss f systms. Rlblty ngnrng dls wth th prdctn, prvntn, nd mngmnt f hgh lvls f "lftm" ngnrng ncrtnty nd rsks f flr. lthgh stchstc prmtrs dfn nd ffct rlblty, rlblty s nt nly chvd by mthmtcs nd sttstcs. "Nrly ll tchng nd ltrtr n th sbjct mphsz ths spcts nd gnr th rlty tht th rngs f ncrtnty nvlvd lrgly nvldt qntttv mthds fr prdctn nd msrmnt." Fr xmpl, t s sy t rprsnt "prbblty f flr" s symbl r vl n n qtn, bt t s lmst mpssbl t prdct ts tr mgntd n prctc, whch s mssvly mltvrt, s hvng th qtn fr rlblty ds nt bgn t ql hvng n ccrt prdctv msrmnt f rlblty. Rlblty ngnrng rlts clsly t Qlty ngnrng, sfty ngnrng, nd systm sfty, n tht thy s cmmn mthds fr thr nlyss nd my rqr npt frm ch thr. t cn b sd tht systm mst b rlbly sf. Rlblty ngnrng fcss n th csts f flr csd by systm dwntm, cst f sprs, rpr qpmnt, prsnnl, nd cst f wrrnty clms.