1. Anonymous Connections and Onion Routing
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2. Is Internet
communication
private?
Anonymous Connections and Onion Routing
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3. Types of Attacks
Active Attacks
Passive Attacks
Anonymous Connections and Onion
Routing
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4. Active Attack
Anonymous Connections and Onion
Routing
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5. Passive Attack
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Routing
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6. Eavesdropping
What is going
on inside?????
Eavesdropping is the act of secretly
listening to the private conversation of
others without their consent.
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7. Onion Routing
Sender and the receiver nodes communicate
with each other anonymously by means of
some intermediate nodes called as onion
routers.
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8. Network
Infrastructure
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9. Proxy Interfaces
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10. Anonymous Connections and Onion Routing
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11. Defining a route
Constructing an anonymous connection and
onion
Moving onion through an anonymous
connection
Destroying the anonymous connection
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12. Anonymous Connections and Onion Routing
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13. E4pu (3’s IP address, E3pu ((5’s IP address,
(E5pu (recipient’s IP address, data)))))
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14. Anonymous Connections and Onion Routing
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15. Anonymous Connections and Onion Routing
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16. Anonymous Connections and Onion Routing
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17. The size of the onion reduces as it nears
the destination
Every onion router has details of only its
previous and next hop
An attacker might compromise a router,
acquires private key and decrypts data.
Packet delivery is not ensured
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18. Anonymous Chatting
Web Browsing
Electronic
Mail
Remote Login
Anonymous Cash
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19. •The purpose of onion Routing is to protect the
anonymity of a user who wants to communicate
over a network.
•Resistant to Eavesdropping.
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20. References
http://www.ietf.org/rfc/rfc793.txt
M. Reed, P. Syverson, D. Goldschlag, "Anonymous
Connections and Onion Routing",
IEEE Symposium on Security and Privacy (1997)
http://tor.eff.org/tor-design.pdf
http://tor.eff.org/
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