Master of Science thesis Fighting Spam

5.6.1 Økonomisk misbrug ..................................................................................49
5.6.2 Netværkstrusler .........................................................................................50
5.6.3 Fysiske trusler ...........................................................................................51
6 Design .......................................................................................................................53
6.1 Systemstruktur...................................................................................................53
6.1.1 Infrastruktur...............................................................................................53
6.2 Autentifikation ..................................................................................................54
6.2.1 Oprettelse ..................................................................................................54
6.2.1.a Traditionelt certifikatsystem ................................................................. 55
6.2.1.b SpamCash certifikatsystem ...................................................................55
6.2.2 Pengeoverførsler........................................................................................56
6.3 Design af elektroniske penge ............................................................................56
6.3.1 Betaling .....................................................................................................57
6.3.2 Møntstruktur..............................................................................................58
6.3.2.a Transaktionslisten..................................................................................59
6.3.3 Økonomisk misbrug ..................................................................................61
6.3.3.a Modifikation..........................................................................................61
6.3.3.b Tyveri ....................................................................................................62
6.4 Blacklisting .......................................................................................................63
6.4.1 Opdatering af blacklist ..............................................................................64
6.4.2 Detektion af kopier....................................................................................66
6.4.2.a Detektion i pengeserver.........................................................................66
6.4.2.b Detektion i klient...................................................................................66
6.5 Anonymitet........................................................................................................67
6.5.1 Anonymitet overfor systemet....................................................................67
6.5.2 Anonymitet overfor andre brugere............................................................68
6.6 Use-cases...........................................................................................................69
6.6.1 Use Case 1a: Start program.......................................................................69
6.6.2 Use Case 1b: Start program.......................................................................70
6.6.3 Use Case 2: Konfigurer program ..............................................................70
6.6.4 Use Case 3: Penge-status...........................................................................70
6.6.5 Use Case 4a: Afsend email .......................................................................71
6.6.6 Use Case 4b: Afsend email .......................................................................71
6.6.7 Use Case 5: Modtag email ........................................................................71
6.6.8 Use Case 6: Indkasser SpamCash ..........................................................72
6.6.9 Use Case 7: Hæv Penge ............................................................................72
6.6.10 Use Case 8: Indløs penge ..........................................................................73
6.6.11 Use Case 9: Tilføj email til whitelist.........................................................73
6.6.12 Use Case 10: Fjern email fra whitelist ......................................................73
6.6.13 Use Case 11: Luk program........................................................................74
6.7 Sikkerhed...........................................................................................................74
6.7.1 Lokal sikkerhed.........................................................................................74
6.7.2 Netværkssikkerhed....................................................................................75
6.7.3 Nøglestørrelser ..........................................................................................75
6.8 Kommunikationsprotokoller og serverdesign ...................................................77
6.8.1 Servere.......................................................................................................77
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