ADDRESS MAPPING (MULTIPLE CHANNELS) C Row (14 bits) Bank (3 bits) Column (11 bits) Byte in bus (3 bits) Row (14 bits) C Bank (3 bits) Column (11 bits) Byte in bus (3 bits) Row (14 bits) Bank (3 bits) Column (11 bits) Byte in bus (3 bits) Row (14 bits) Bank (3 bits) C Column (11 bits) C Byte in bus (3 bits) • Where are consecutive cache blocks? C Row (14 bits) High Column Bank (3 bits) C High Column Bank (3 bits) High Column C Bank (3 bits) High Column Bank (3 bits) High Column 8 bits Low Col. Byte in bus (3 bits) C Low Col. Byte in bus (3 bits) 3 bits 8 bits Row (14 bits) Byte in bus (3 bits) 3 bits 8 bits Row (14 bits) Low Col. 3 bits 8 bits Row (14 bits) Byte in bus (3 bits) 3 bits 8 bits Row (14 bits) Low Col. Bank (3 bits) Low Col. C Byte in bus (3 bits) 3 bits 47
View full slide show




Ron’s Code or Rivest Codes Scorecard Description RC2 RC4 RC5 RC6 Timeline 1987 1987 1994 1998 Type of Algorithm Block cipher Stream cipher Block cipher Block cipher Key size (in bits) 40 and 64 1 - 256 0 to 2040 bits (128 suggested) 128, 192, or 256 Variable key-size block cipher that was designed as a "drop-in" replacement for DES. Use Most widely used stream cipher based on a variable key-size Vernam stream cipher. It is often used in file encryption products and secure communications, such as within SSL. The cipher can be expected to run very quickly in software and is considered secure. © 2012 Cisco and/or its affiliates. All rights reserved. A fast block cipher that has a variable block size and key size. It can be used as a dropin replacement for DES if the block size is set to 64-bit. An AES finalist (Rijndael won). A 128-bit to 256- bit block cipher that was designed by Rivest, Sidney, and Yin and is based on RC5. Its main design goal was to meet the requirement of AES. 104
View full slide show




Output FeedBack (OFB)  message is treated as a stream of bits  output of cipher is added to message  output is then feed back (hence name)  feedback is independent of message  So feedback can be computed in advance
View full slide show




Substitution Cryptosystems  How many possible keys does an affine cipher on have? 7. Encrypt using a rotation cipher over with . 8. Encrypt using an affine cipher over with 9. Cipher X consists of a rotation, and then an affine cipher. What type of cipher is X? 10. Cipher Y is a substitution cipher over . Cipher consists of applying Y twenty-four times. What type of cipher is X? Be as specific as possible. 6.
View full slide show




An Ontology level is needed XML Ontology 256 imports Ontologies add • Structure • Constraints • mappings imports XML Ontology 1 XML Ontology 42 = <> We need a way to define ontologies in XML So we can relate them So machines can understand (to some degree) their meaning
View full slide show




MIPS R-format for the add instruction op rs rt rd shamt funct 6 bits 5 bits 5 bits 5 bits 5 bits 6 bits • For add, $t0, $s1, $s2 – – – – – – op = 0 (for add) rs = $s1, register 17 rt = $s2, register 18 rd = $t0, register 8 shamt = 0 (for add) funct = 32 (for add) add instruction syntax: add rd, rs, rt (See the green card in the textbook) Q1: why 5 bits for register values??? 0 17 18 8 0 32 6 bits 5 bits 5 bits 5 bits 5 bits 6 bits 000000 10001 10010 01000 00000 100000 6 bits 5 bits 5 bits 5 bits 5 bits 6 bits Q2: What is the hex equivalent?
View full slide show




Stream versions of list functions (define (snth n stream) (if (= n 0) (scar stream) (snth (sub1 n) (scdr stream)))) (define (smap f stream) (if (snull? stream) sempty (scons (f (scar stream)) (smap f (scdr stream))))) (define (sfilter f stream) (cond ((snull? stream) sempty) ((f (scar stream)) (scons (scar stream) (sfilter f (scdr stream)))) (else (sfilter f (scdr stream)))))
View full slide show




Stream versions of list functions (define (snth n stream) (if (= n 0) (scar stream) (snth (sub1 n) (scdr stream)))) (define (smap f stream) (if (snull? stream) sempty (scons (f (scar stream)) (smap f (scdr stream))))) (define (sfilter f stream) (cond ((snull? stream) sempty) ((f (scar stream)) (scons (scar stream) (sfilter f (scdr stream)))) (else (sfilter f (scdr stream)))))
View full slide show




We’ll need stream versions of other familiar list manipulation functions (define (snth n stream) (if (= n 0) (scar stream) (snth (sub1 n) (scdr stream)))) (define (smap f stream) (if (snull? stream) sempty (scons (f (scar stream)) (smap f (scdr stream))))) (define (sfilter f stream) (cond ((snull? stream) sempty) ((f (scar stream)) (scons (scar stream) (sfilter f (scdr stream)))) (else (sfilter f (scdr stream)))))
View full slide show




1. Insert students’ names in alphabetical order Name Name Name Name Name Name Name Name Name Name Name Name Name Name Name Name Name Name Name Name Name Name Name Name Name
View full slide show




We’ll need stream versions of other familiar list manipulation functions (define (snth n stream) (if (= n 0) (scar stream) (snth (sub1 n) (scdr stream)))) (define (smap f stream) (if (snull? stream) sempty (scons (f (scar stream)) (smap f (scdr stream))))) (define (sfilter f stream) (cond ((snull? stream) sempty) ((f (scar stream)) (scons (scar f) (sfilter f (scdr stream)))) (#t (sfilter f (scdr stream)))))
View full slide show




Cipher Block Chaining • cipher block: if input block repeated, will produce same cipher text: t=1 … m(17) = “HTTP/1.1” t=17 • cipher block chaining: XOR ith input block, m(i), with previous block of cipher text, c(i-1) – c(0) transmitted to receiver in clear m(1) = “HTTP/1.1” block cipher c(1) block cipher c(17) m(i) c(i-1) + block cipher c(i) = “k329aM02” = “k329aM02”
View full slide show




Cipher FeedBack (CFB)    message is treated as a stream of bits or bytes result is feed back for next stage (hence name) standard allows any number of bit (1,8, 64 or 128 etc) to be feed back   denoted CFB-1, CFB-8, CFB-64, CFB-128 etc most efficient to use all bits in block (64 or 128) Ci = Pi XOR EK(Ci-1) C-1 = IV  Used for stream data encryption
View full slide show




C Data Types Data type bool char signed char unsigned char signed short unsigned short signed int unsigned int signed long unsigned long signed long long unsigned long long Size 8 bits 8 bits 8 bits 8 bits 16 bits 16 bits 16 bits 16 bits 32 bits 32 bits 64 bits 64 bits float double double 32 bits 32 bits 64 bits Range Alignment 0 to 1 1 to 255 1 -128 to 127 1 0 to 255 1 -32768 to 32767 2 0 to 65535 2 -32768 to 32767 2 0 to 65535 2 -231 to 231-1 2 0 to 232-1 2 63 63 -2 to 2 -1 2 64 0 to 2 -1 2 2 2 (*) CPE 323 Intro2EmbeddedSys 40
View full slide show