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/L/L 5L⊕)/L.L Input.KÖÝLWDÑRKRDÛQYÔL1=RoRo+F+F+F³DÝRNKÖÝLWDÑRKRÛDQYÔ2XWSXWLoR1 = Lo + F(R1,K1)L15 = R14R2 = L1 + F(R1,K2)L2 = R1R15 = L14 + F(R14,K15)+FR16 = L15 + F(R15,K16)L16 = R151,2,3, . 64 1,2,3, . 64 1,2,3, . 32K1K2KnK16Hình 1: Encryption computation1,2,3, . 32 &KRÑQKRÛDQYÔ/HIW6KLIW /HIW6KLIW/HIW6KLIW/HIW6KLIW/HIW6KLIW /HIW6KLIW&KRÑQKRÛDQYÔ&KRÑQKRDÛQYÔ&KRÑQKRDÛQYÔ1,2,3, . 641,2,3, . 28 1,2,3, . 28K1KnK16+ÎQK Key Schedule CalculationKeyKey KeyC1D1Cn DnC16D16 S1S2S3S6S5S7S4S8P32 bits+E48 bitsK (48 bits)5ELWVHình 3 : Calculation of f(R,K)64 %DÝQJD%DÝQJKRDÛQYÔÓDÂXWLHÄQ,3  %DÝQJE%DÝQJKRDÛQYÔFXRÃLFXÚQJ,3%DÝQJ%DÝQJFKRÑQEÏW( %DÝQJ%DÝQJKRDÛQYÔ3%DÝQJ%DÝQJKRDÛQYÔNKRÛD3& %DÝQJ%DÝQJKRDÛQYÔNKRÛD3&                        &ROXPQ5RZ%R[66666666%DÝQJ%DÝQJFKRÑQ6ER[H[ '(6,Q(OHFWURQLF&RGH%RRN0RGH(&%ảẵPRGHQD\FDFNKRLGDWDGỉệLGDẹQJURíFOHDUWH[WểỉệẹFểỉDYDRLQSXWFXíD'(6&DFNKRLNHWTXDíGỉệLGDẹQJPDặWPDìFLSKHUWH[WFRWKHầểỉệẹFVỉíGXẹQJFKRFDFỉQJGXẹQJNKDF4XDWUẻQKELHQểRầLGLHQUDQKỉVDXKẻQK&OHDUWH[Wặ,QSXWEORFNặ'(6ặ2XWSXWEORFNặ&LSKHUWH[W(&%HQFU\SWLRQ (&%GHFULSWLRQ+ẻQK(OHFWURQLF&RGHERRN0RGH(&%'(6,Q&LSKHU%ORFN&KDLQLQJ0RGH&%&.KRLGDWDFDQPDìKRDểỉệẹFFKLDWKDQKFDFNKRL%%g%QYệLNẽFKWKỉệFPRLNKRLODELWV9HFWệNKệíLWDẹR,9ELWVểỉệẹFFKRẹQ6ệểRPDặWPDìểỉRẹFFKRWURQJKẻQK4XDWUẻQKPDìKRD,9%&&OHDUWH[W''',QSXWEORFN,,g,'(6HQFU\SW2XWSXWEORFN22g2&LSKHUWH[W&&g&&OHDUWH[W'''&LSKHUWH[W&&g&,QSXWEORFN,,g,'(6GHFU\SW2XWSXWEORFN22g20Dì KRD &⊕%& Q&Q⊕%Q&Q 4XDÛWUÎQKJLDÝLPD×& ,9⊕%,9⊕%⊕,9 %& &⊕%&⊕%⊕& % &Q&Q⊕%Q&Q⊕%Q⊕&Q %Q+ÎQK&LSKHU%ORFN&KDLQLQJ&%&PRGH*LDÝL PD×,9 %%%3 Time = 1 Time = 2Time = n + + +,,,'(6HQFU\ '(6HQFU\ '(6HQFU\&&&Q ., , ,'(6GHFU\ '(6GHFU\ '(6GHFU\,9 + + +%%%3 0D×KRÛD*LDÝLPD× 123doc.vn

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