Optimistic fair exchange for secure forwarding

Önen, Melek;Shikfa, Abdullatif;Molva, Refik
SPEUCS 2007, 1st Workshop on the Security and Privacy of Emerging Ubiquitous Communication Systems, August 10, 2007, Philadelphia, USA

Several cooperation enforcement schemes based on

rewarding mechanisms such as electronic cash or online credits

have lately been proposed to prevent selfish behavior in ad-hoc

networks. However, these schemes suffer from the lack of fairness

guarantees or the reliance on costly mechanisms such as tamperproof

hardware or the requirement for Trusted Third Parties

(TTPs) that are not suitable for ad-hoc networks.

In this paper, we present a new cooperation-enforcement

scheme that is perfectly suitable for ad-hoc delay-tolerant networks.

The protocol is based on a simple technique called hotpotato

forwarding whereby in order to receive a packet, potential

recipients must first deliver an advance reward to the sender

prior to the transmission of the packet. Thanks to this technique

cooperation among nodes becomes mandatory and poisoning

attacks and cheating actions are inherently prevented. The second

contribution in our scheme is an optimistic fair exchange protocol

that solves the fairness problem that is inherent to peer rewarding

schemes. The protocol achieves total fairness with the help of

a TTP and is optimistic in that the TTP is only involved in

case of conflict between peer nodes. Correct execution of the

protocol does not require any access to the TTP, so fairness is

achieved without any impact on well-behaving nodes. The fairness

of the protocol is validated through the exhaustive analysis of all

possible protocol traces.


Type:
Conférence
City:
Philadelphia
Date:
2007-08-10
Department:
Sécurité numérique
Eurecom Ref:
2299
Copyright:
© EURECOM. Personal use of this material is permitted. The definitive version of this paper was published in SPEUCS 2007, 1st Workshop on the Security and Privacy of Emerging Ubiquitous Communication Systems, August 10, 2007, Philadelphia, USA and is available at :

PERMALINK : https://www.eurecom.fr/publication/2299