State University of Telecommunications

1. State University of Telecommunications Line cipher demonstration for educational purposes P.M. Tutunnick, paul_3@front.ru Advisor: D.V. Kushnir

2. Outline • Cryptology basics: • Subject and main directions • Binary functions • The overview of “Virtual University” complex creation history • Main principles of PC-based laboratory exercise • “LogiCon” experimentation tool introduction: • Nature and general purpose • Main features list • Engine functionality basics • Interface capablities • Application example: • “Exploration of Line-Recurrent Register” exercise • Key generator projects contest • Complex adapation posiblities • Alternative use directions • Progress perspectives

3. Cryptology Subject Science about safety of communications Cryptography Cryptanalysis The science studying principles, methods and means of transformation of the information for its protection against unauthorized access and distortion. The science studyingprinciples of possible cryptoatacks, and measuring defensive potential of cryptosystems.

4. Cryptography directions • Types of important information, that needs to be protected: • State secret • Military secret • Commercial secret • Jurisprudential Secret • Medical secret • etc. It provides: • Secrecy of stored private information • Safety of messaging • Users autentification • Security of algorithms • Passwords & keys management • Objects to protect : • Encryption and decryption algorithm • Transmitting channels • Encryption details • User co-ordinates • Fact of encrypted transmittion

5. Tipical Cryptosystem Model Simple Ciphers: Main Types of Attacks : • Replacement ciphers (Lisandr, “Scitala”) • Switching ciphers (“Caesar cipher”) • Statistical (“linguoanalysis”) attac • Algorithm (“exploit”) attack • Chosen content (“user”) attack • Block-revealing (“vocabulary”) attack • Power (“all-key”) attack • Destructive (“heating”) attack • etc.

6. Binary Functions y=F(x1,x2,..xn) Decimal (Multiplexing) Binary (OR operation) Binary Basis 3D Basis “NOT” “AND” “OR”

7. Basis Functions Combining Example:“XOR” Operator x1 x2 y 0 0 0 0 1 1 1 0 1 1 1 0

8. “Virtual university” project complex • Started: 1993 • Developed by: teachers and students of SUT ITTERC • Meant to: assist the educational courses by interactive demonstration of it’s subjects and systematyse already existing thematical computing researches • Now allows to: • Provide high-quality visual & interactive representings of described physical & logical processes • Fully automatyse technicaly aspects of educational processes • Stimulate new researches by integrating it in earlier application packages • Complete practical tasks remotely via internet • Use virtual laboratories for performing topical experiments of any kind without any additional equipment

9. Cryptography Steganography Programming on C Language Programming on Assembler Language High Level Programming Computing Support of Engeneering ElectroCommunications Theory SchemoTechnics Basics Digital Processing of Signals Military practice Subjects of University, in which project components are employed: Most of program complexes developed by ITTERC are integrated in the common database system that provides user access, basing on a Smart-Card technology, and contains student practice real-time statistics.

10. PC-based practice program properties: • Educational utility • Clear work plan • Interactive elucidative texts • Not too formal and easy to perform • Acceptable visualization quality • Unified interface functionality • Wide experimental capabilities • Controling and score-counting tools • Integrated client-server system • Modification abilities

11. Virtual Logical Models Constructor Utilityaka LogiCon - Multipurposal educational desighning toolset package, that allows to create, redact and analyse fully operational logical schemes of different sorts. - Was developed in 2004 for demonstration of cryptography basic algorithms. - Upgraded to provide experience of exploring and development of abstract logic schemes, allowing to applicate it more effectively and widely. - Is currently bypassing final adaptation and tests before getting into exploitation.

12. LogiCon Project main features list • Flexible logical functionality • User-friendly interface • Drag’n’drpop-based workspase • Rich set of pre-programed logical elements • Nearly unlimited number of construction blocks • Blocks flexible tuning ability • Multi-level logic desighn • File-level exchange • Built-in script sublanguage • Abitity to model occasionaly events • Statistic analiser tools • Interactive guiding informer • Smart result-checking system

13. LogiCon Engine functionality basics: “block” • Primary construction element • Low-level defined visual object • Provides inner data processing • Input/Output • Registers • Functions • Custom Operators Each kind of element is supported with a individual settings system with a simple access by a pop-up menu, allowing to change block options swiftly without replacing it.

14. LogiCon Engine functionality basics: “link” • Single-sided connection between blocks • Defined as a block logical property • Delivers the binary calculation results User-established links define a scheme graph virtual matrix, allowing it to perform logical operations. LogiCon Engine functionality basics: “phase” • Standart, constantive state of a scheme • Untill switched all digital values remain unchanged Proceeding to the next phase allows to spectate sceme operating step-by-step and to receive the intermediate resultsof process.

15. Logicon Interface Components Stand-Alone Component System Menu Availible Components Zoom-In/Out Switch to Next/Previous Phase Desighn Space

16. Block Ciphering Stream (Line) Ciphering Joining Algorithm

17. Simple stream cipher algorithm Encryption Decryption

18. LogiCon representation Decryption Encryption Transmission

19. Linear recurrent register shift algorithm n B0,2=F(B2,1,B7,1) T=2n-1

20. Modified (switching) key generator T=T1.T2.T3

21. Thank you for attention!Спасибо за внимание! LogiCon paul_3@front.ru www.uicitt-sut.spb.ru