1. Protocol Steganography Norka Lucena and Steve Chapin Syracuse University May 27, 2004

2. What is Protocol Steganography? Embedding information within messages and network control protocols used by common applications Embedding information within messages and network control protocols used by common applications UDP FTP TCP SSH HTTP SMTP Etc.

3. Sender sends message m Sender sends message m Protocol Steganography Framework Alice intercepts m, hides some information on it, and sends m’ Alice intercepts m, hides some information on it, and sends m’ Bob received m’ and sends either m or m’ Bob received m’ and sends either m or m’ SenderReceiver AliceBob m m or m’ m’Eve/Mallory

4. Protocol Steganography Framework Six possible sets of agent roles Six possible sets of agent roles

5. Problem: Appropriate Location of the Agents How to guarantee that Bob will actually get the stegopacket sent by Alice ? How to guarantee that Bob will actually get the stegopacket sent by Alice ? How to place Alice and Bob such that the susceptibility traffic analysis is minimized? How to place Alice and Bob such that the susceptibility traffic analysis is minimized?

6. Any questions or insights?