Routing Table and Messages Extensions e Add three fields into original routing table ■ Positive events a Negative events ■ Opinion New routing table format DestlP DestSeq HopCount Lifetime Positive Negative Opinion Events Events o Add trust information into original aodv outing messages a RREQ>Trusted RREQ (TRREQ) a RREP> Trusted RREP (TRREP 21 May 29, 2009 CSE CUHK
21 May 29, 2009 CSE CUHK Routing Table and Messages Extensions ◆ Add three fields into original routing table: ◼ Positive events ◼ Negative events ◼ Opinion ◆ New routing table format ◆ Add trust information into original AODV routing messages. ◼ RREQ → Trusted RREQ (TRREQ) ◼ RREP → Trusted RREP (TRREP) DestIP DestSeq ... HopCount ... Lifetime Positive Events Negative Events Opinion
Trust Judging Rules o Predefined trust judging rules b d u Actions >h Request and verify digital signature >h Distrust a node for an expire time h Trust a node and continue routing ≤h≤h Request and verify digital signature b- belief d-disbelief u-uncertaint h-threshold which can be adjusted to meet different applications (default h=0.5) 22 May 29, 2009 CSE CUHK
22 May 29, 2009 CSE CUHK Trust Judging Rules b – belief d – disbelief u – uncertainty h – threshold which can be adjusted to meet different applications (default h=0.5) b d u Actions > h Request and verify digital signature > h Distrust a node for an expire time > h Trust a node and continue routing ≤ h ≤ h Request and verify digital signature ◆ Predefined trust judging rules
Trust Updating Policies ◆ Update of evidences Successful communication> Positive events Increased a Failed communication Negative events increased a Mapping from opinion space ◆ Update of opinions a Combination from recommendations a Mapping from evidence space 23 May 29, 2009 CSE CUHK
23 May 29, 2009 CSE CUHK Trust Updating Policies ◆ Update of evidences ◼ Successful communication → Positive events increased ◼ Failed communication → Negative events increased ◼ Mapping from opinion space ◆ Update of opinions ◼ Combination from recommendations ◼ Mapping from evidence space
Trust Recommendation Protocol Exchange trust information o Three types of messages ■TREQ: Trust REQuest TREP: Trust REPly TWARN: Trust WARNing Message structure Type Requestor Recommender Recommendee Opinion Class Expiry 0--TREO belief disbelief uncertainty 1-- TREP 2-- TWARN 24 May 29, 2009 CSE CUHK
24 May 29, 2009 CSE CUHK Trust Recommendation Protocol ◆ Exchange trust information ◆ Three types of messages: ◼ TREQ: Trust REQuest ◼ TREP: Trust REPly ◼ TWARN: Trust WARNing ◆ Message structure:
Trusted Routing Discovery (1 Scenario 1-Beginning of a TAODV MANET 0A(c=00.1) 0A+0c=(0.330067) Oa=(0.0.1) O0g=03006 O)g=(01) O=(0.33067) Initial opinions are all(,0, 1), set threshold h=0.5 a node a broadcasts trreq to discover a route to c Node b will authenticate a and c because of high uncertainty values(u=1)in its opinions to A and c a Finally if the authentication and the discovery succeed, the opinions all become(0. 33, 0,0.67) 25 May 29, 2009 CSE CUHK
25 May 29, 2009 CSE CUHK Trusted Routing Discovery (1) ◆ Scenario I - Beginning of a TAODV MANET ◼ Initial opinions are all (0,0,1), set threshold h = 0.5 ◼ Node A broadcasts TRREQ to discover a route to C ◼ Node B will authenticate A and C because of high uncertainty values (u=1) in its opinions to A and C ◼ Finally, if the authentication and the discovery succeed, the opinions all become (0.33,0,0.67)