Trust and Reputation Based mechanisms for CIP
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Transcript of Trust and Reputation Based mechanisms for CIP
Trust and Reputation Based mechanisms for CIP
Uniparthenope, UniRC, Polito
(Fai della Paganella, 10-12 Febbraio 2014)
Objectives
• To enhance the cyber security of Wireless Sensor Networks (WSNs) deployed to protect CIs by exploiting Trust and Reputation Model based techniques – Intrusion Tolerance at the routing level
Security of WSNs
• WSNs have low computational resources and energy supply– Limit the number of exchanged messages– Limit the usage of cryptographic mechanisms
• WSNs are deployed in unattended, hostile, environments
Trust and Reputation
A trust and reputation model is proposed to improve cyber defense. Say Node 3 wants to estimate trust and reputation perceived about Node 2:• Node 3 estimates a trust score of Node 2 through a direct measure
related to Node 2• Node 3 estimates a reputation score of Node 2 through indirect
measurements, e.g. by observing the trust level perceived by Node 1 wrt Node 2
Attack Model: Sinkhole Attack
• Trust and reputation-based scores to ensure resilience against attacks such as sinkhole
No attack
Node 3 successfully attacks(BS = Base Station)
Trust and Reputation Model
The model proposed acts as follows:1. When Node 3 starts an attack, by pretending to
have the best route toward destination, we need:1. A reliable way to check
if it is lying (to measure trust)2. A way to share this
information (to update neighbourns reputation)
(BS = Base Station)
Test of Trustworthiness
Assuming to have a routing protocol enabling parties authentication 1. Node 4 forces a ping through two alternate paths one of
which includes the node under test2. Node 4 chooses the route with lower round trip time 3. If the selected path does not use the tested node as
gateway the trust level of node 3 is lowered – T43(t+1) = k* T43(t) k < 1
3
Reputation
• If a change in the trust level of node 3 is going to occour, node 4 forwards a feedback to each of the nodes in its neightbour list.
• Each node receiving the feedback accordingly corrects the reputation of node 3– Ri3(t+1) = f(Ri3(t), ΔT43)
Intrusion Tolerance
• When a node must select a parent to reach the BS this evaluation will be based on: quality of the channel, trust level, and reputation level of the candidate node.– That is a Dependability function is evaluated for
each candidate and the new parent will be the one with highest dependability value:• For each j in N: Dij(t+1) = f(Qij(t), Tij(t),Rij(t)) (N set of
neighbours)• The node j such that Dij(t+1) =Max(Dij(t+1)) is selected as
the parent one
AODV Routing Protocol
• Ad hoc On Demand Distance Vector (AODV) is a standard routing protocol defined by RFC 3561 (http://www.ietf.org/rfc/rfc3561.txt)
• AODV is widely adopted e.g. in Bluetooth and Zigbee
http://www.bluetooth.com/
http://www.zigbee.org/
Implementation
• A WSN was simulated through NS-3
• NS3 is a command-line, open source (GNU GPL v2) network simulator
• Programming languages: C++, Python• Different WSNs routing protocols are implemented
such as Optimized Link State Routing Protocol (OLSR) and Ad hoc On Demand Distance Vector (AODV)http://www.nsnam.org/
Future Steps
• To complete implementation
• To test the effectiveness of the proposed model under different testbed configurations, and parameters tuning
• To extend the approach to manage other kind of attacks