1 / 16

Encoding and encryption

Encoding and encryption. Overview of encodings and ciphers in real life. Juraj Vančo 93. p rístav vodných skaut o v a skautiek Tortuga Trenčín Sep 2013. Agenda. Encoding and encryption Encodings in real life Morse code Where to find Q codes QSL SSL encryption Digital signature.

cicero
Download Presentation

Encoding and encryption

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Encoding and encryption Overview of encodings and ciphers in real life Juraj Vančo 93. prístav vodných skautov a skautiek Tortuga Trenčín Sep 2013

  2. Agenda • Encoding and encryption • Encodings in real life • Morse code • Where to find • Q codes • QSL • SSL encryption • Digital signature

  3. Encoding and encryption • Encoding • procedure with goal to change information to be easier in practise • every information needed to proceed is available for everyone • example: Morse code • Encryption • procedure with goal to hide information that cannot be read from those who do not have the knowledge how to extract (decrypt) the useful information • example: private translation table

  4. Encodings in real life • Pictograms, abbreviations with the only meaning • Morse code • Where? Telegraph + air communication: aviation, navy, HAM radio • Information: table + procedure • Lossless compression / decompression (LZHA = zip, gzip, bzip, rar) (information accumulation) • Information: procedure = algorithm • Email encodings with base64 algorithm • Information: procedure = algorithm

  5. Morse code • What for? Frequency band and filtering • Timing encrypted • Consequences: messaging (transmitting) procedure can take much time compared to speech => issues with oscillators characteristics bias in time • Solution: timing as fast as human can (200 letters / min) • Solution: using Q-codes (encodings) • Dots and lines? No use case in real life… • Replacement: phone (codes and spelling alphabet)

  6. Q codes • 3 letters codes replacing more complex information • Examples: • QSL • QTH • QSO • QRA • QRL

  7. Example of QSO »QRL? »CQ CQCQ de OM4ATN «OM4ATN de HB9ASD K »HB9ASD de OM4ATN TNX FER QSO QTH QTH TRENCIN RST 577 NAME JURAJ PSE QSL K «OM4ATN de HB9ASD TNX UR RST 599 QTH QTH GENEVA NAME JEAN WX CLOUDY PSE UR WX UR WX K »HB9ASD DE OM4ATN TNX FER QSL WX WX SUNNY 23C K «OM4ATN DE HB9ASD R R OK DR JURAJ TNX CU K »HB9ASD DE OM4ATN TNX CU SK

  8. Encryption in real life • Private translation table (can have additional key= shift etc.) • Code Navaho (table= key) • Security = Privacy, Integrity, Authentication • Symmetric and asymmetric encryption algorithms (AES, DES, 3DES, DSA, RSA…)- (known algorithm, unknown key) • Challenge: decrypt! • Scouting: messages that are “easy” to decrypt but take time (“4 ohne, Boj o pokladkapitána pirátov”) • IT- compute power: bunch of methods => easy to find the translation • Algorithm based encryption= no key= vulnerable algorithm • Key based= algorithm is known= find the key (brutal force attack)

  9. Encryption: symmetric and asymmetric • Keys: both must know the key, how to?

  10. Authentication: certificates & PKI

  11. Example of certificate #1

  12. Example of certificate #2

  13. Example of certificate #3

  14. Digital signature • Hash = Digitally encoded „abstract“ • integrity number, no real information inside • Digital signature = hash + certificate

  15. Other risks • Unsecured WiFi network • Running untrusted software without certification (Windows) • Use sigverif.exe in Windows command prompt • Unknown hardware • Keyboards, computers, fingerprint scanners…

  16. Q & A • Thanks for watching

More Related