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Why r@(doesnt the Clark-Wilson Model do this? s x( 25 points ) Consider the following protection mechanism. Each object and each process is assigned a number. A 0nprocess can only access an object if the object has a higher number than the process. Which of the mechanisms hdiscussed in class (ACL, capabilities, lock-and-key, the MULTICS ring protection scheme) does this most @dclosely resemble, and why? In what essential way does it differ from the scheme discussed in class? t u( 25 points ) Assume the Clark-Wilson model is implemented on a computer system. Could a computer virus that 0oscrambled constrained data items be introduced into the system? Why or why not? Specifically, if not, identify mthe precise control that would prevent it from being intorduced, and say why it would prevent the virus from tbeing introduced; if yes, identify the specific control or controls that allow it to be introduced and say why they @fail to keep it out. w` Extra Credit u`,( 10 points ) Chapter 7, exercise 4 Aj`9( 5 points ) Chapter 7, supplementary exercise 1 HHˆ5HHˆl}: G eParagraph Format }:!G e Comments }l: )lGe2 d9#'H$ 9"%H$ $$ l H$ 9"H$ #WhT XDecember 3, 1999 Y ECS 153 F ALL  1999 Page  [1 \ HUV 9"#'HUV && l HUV 9"HUV %W l6Version of   aNovember 28, 1999 11:29 pm U HHˆ9"%HHˆ(( l HHˆ9"HHˆ'W ` }:!*GUTe Heading1 }:)uGe d:8-- $$:9+$$0a-0XSNID?:50+& }x l^bf~zvrnjUX[IMQ.14FC@=:7GBm ` _ ^ ] Z W $$:;+$$%,,l}$ :>iT1$ jWeCharacter Macros }l :@il jWe } :Bi jWe }$H:Di.2$HjW e Character }l:Fi13ljW e Replace With }:Hi24jW e Comments }$H:Ji35$HjW e }l:Li46ljW e¢ }:Ni5FjW e }$H:{i<8$HjW e }l:}i79ljW e... }:i8jW e }$H:i?;$HjW e }l:i:<ljW e- }:i;7jW  e }$H:iB>$Hj W! e }l:i=?lj W" e-- }:i>:j W# e }$H:iEA$Hj W$ e }l:i@Blj W% e° }:iA=j W& e }$H:iHD$Hj W' e }l:iCElj W( e® }:iD@j W) e }$H:i6G$Hj W* e }l:iFHlj W+ e© }:iGCj W, e }$Z :i]M$Z j W-eGeneral Macros }Z :iZ j W.e }Z :iZ j W/e }\Z :i\Z j W0e }$jh:iIN$jhjW1 e Macro Name }jh:iMOjhjW2 e Replace With }jh:iNPjhjW3 eHead }\j:iOQ\jjW4 e Comments }$zh:iPR$zhjW5 e }zh:iQSzhjW6 e }zh:iRTzhjW7 e }\z:iS.\zjW8 e }$$ ;imX$$ j W9eCross-Reference Macros }$ ;i$ j W:e }D$ ;iD$ j W;e }$4;iUY$4j W< e Macro Name }4; iXZ4j W= e Replace With }D4;"iY[D4j W> e Comments }$D;$iZ\$Dj W? 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