Covert Channels and Anonymous Communication in Ad-hoc Networks

Ad-hoc wireless networks distinguish themselves from their traditional wired counterparts by three unique characteristics: mobility, lack of infrastructure, and shared wireless channel. These properties have gained popularity in various military and civilian applications, but have also introduced challenging problems in terms of ensuring satisfying network performance and network security. Ad hoc networks are a fertile ground for new threats and security problems. We start by demonstrating how new covert attacks can be launched by using the ad hoc network protocols. In particular, nodes in ad-hoc wireless networks have to cooperate with each other in order to accomplish many networking functions such as routing and channel access. We observe that covert information can be conveyed during the cooperation procedure. It is very difficult to eliminate or even detect these covert channels. Simulation results show that performance of these covert channels depends on various network characte…

Author: Li, Song

Source: University of Maryland

Download Link: Click Here To Download This Report

Reference URL: Visit Now

Reference URL: Visit Now

Contents

1 Introduction
1.1 Covert Channels in Ad Hoc Networks
1.2 Anonymous Communication in Ad Hoc Networks
1.3 Anonymous Authentication with Distributed Anonymity Revocation
1.4 Outline of Thesis
2 Covert Channels in Ad Hoc Networks
2.1 Motivation
2.2 Covert Operations through the Use of Reactive Routing Protocols
2.2.1 Overview of AODV
2.2.1.1 The On-demand Mechanism
2.2.1.2 Sequence Number
2.2.1.3 Route Table Management
2.2.1.4 Route Maintenance
2.2.1.5 Expanding Ring Search Technique
2.2.2 Covert Channels in AODV
2.2.2.1 Timing the Route Request
2.2.2.2 The Source Sequence Number in the Route Request
2.2.2.3 The Lifetime Field in the Route Reply
2.2.2.4 The Destination ID Field in the Route Request
2.2.3 Performance Evaluation
2.2.3.1 Simulation
2.2.3.2 Simulation Results
2.2.4 Detectability
2.2.5 Covert Channels in Other Reactive Routing Protocols
3 Covert Operation through the Use of Splitting Algorithms
2.3.1 Overview of the Splitting Algorithm
2.3.1.1 The Basic Binary Tree Algorithm
2.3.1.2 Improvement 1
2.3.1.3 Improvement 2
2.3.1.4 Unblocked algorithms
2.3.2 Covert Operations through the Use of Splitting Algorithms
2.3.2.1 The Conservative Mode of Covert Operation
2.3.2.2 The Aggressive Mode of Covert Operation
2.3.2.3 The Strategic Mode of Covert Operation
2.3.3 Properties of the Covert Channel in Splitting Algorithms
2.3.4 Detectability
2.3.5 Performance Evaluation
2.3.6 Covert Channels in Other MAC Protocols
2.4 Conclusion
3 Anonymous Communication in Ad Hoc Networks
3.1 Motivation
3.2 Cryptographic Primitives
3.2.1 Hash Function
3.2.2 Trapdoor Function
3.2.3 Pairing Function
3.3 Pairing-based Trapdoor
3.3.1 The Bootstrapping Phase
3.3.2 Pairing-based Trapdoor Construction
3.3.3 Open Trapdoor
3.3.4 Proof of Opening Trapdoor
3.4 Perfect Anonymity vs. Computational Anonymity
3.5 Anonymous Authentication and Key Establishment
3.6 Related Work
3.6.1 Secret Handshakes
4 Anonymous Authentication with Distributed Anonymity Revocation
4.1 Motivation
4.2 Secret Handshakes
4.3 Basic Idea and the Threshold Secret Sharing
4.3.1 Threshold secret sharing
4.4 The AADAR Protocol
4.4.1 Pseudonym generation
4.4.2 Anonymous Authentication
4.4.3 Anonymity Revocation
4.4.4 Blacklist Exchange
4.4.5 Packet-based Pseudonyms
4.5 Discussion
4.5.1 Two Rounds of Secret Handshakes
4.5.2 Distributed Adversary Identiļ¬cation
4.5.3 Threshold
4.5.4 Pseudonym Reloading
4.5.5 An example application of Secure and anonymous routing
4.6 Conclusion
5 Conclusion
Bibliography

Leave a Comment