One Time Password Onno W Purbo Onnoindo net

One Time Password Onno W. Purbo Onno@indo. net. id

Referensi n Buku “Keamanan Jaringan Internet”, Elexmedia Komputindo

Login Normal Red Hat Linux release 6. 0 (Hedwig) Kernel 2. 2. 5 -15 on an i 486 tony login:

Problem n n Password & userid plan text Rentan sniffer Solusi n Password hanya digunakan satu kali n Password berubah setiap kali

Penemu. . n Ide n n Leslie Lamport Software OTP – S/KEY 1991 n n n Phil Karn, KA 9 Q – Bellcore Neil Haler John Walden

Challenge Red Hat Linux release 6. 0 (Hedwig) Kernel 2. 2. 5 -15 on an 1486 tony login: Challenge: 994 672 jar Password:

Challenge dari Server n n Iterasi Seed

Kalkulator Pada Client n n n Seed Iterasi Frasa rahasia client

Kalkulator pada Klien

Responds. . n Tiap client / user akan memberikan kalkulasi responds yang beda karena frasa rahasianya berbeda.

Red Hat Linux release 6. 0 (Hedwig) Kernel 2. 2. 5 -15 on an i 486 tony login: tony Challenge: 994 672 jar Password: Login incorrect login: tony Challenge: 983 672 jar Password: (turning echo on) Password: was leo cal amy tire of Last login: Sun Nov 21 23: 03: 19 from tony [tony @ tony]$

Instalasi OTP n n n Mendapatkan installer OTP untuk sistem Mendapatkan kalkulator untuk client Mengkompile dan melakukan instalasi komponen-komponen OTP Melakukan inisialisasi user dengan kunci masing-masing Meng-enable OTP

Inisialisasi OTP tony. cisitu. net > keyinit Adding wanda: Reminder you need the 6 english words from the skey command Enter sequence count from 1 to 9999: 1000 Enter new key [default nd 12043]: heather S/key 1000 heather S/key access password: ORB HURD LENT CRAM MELD HOSE ID wanda s/key is 1000 heather ORB HURD LENT CRAM MELD HOSE

X Windows tony. cisitu. net login: tony Callenge: 974 672 jar Password: