CryBlock 2019 G-IOTA: Fair and Confidence Aware Tangle Authors: Gewu - PowerPoint PPT Presentation

CryBlock 2019 G-IOTA: Fair and Confidence Aware Tangle Authors: Gewu BU, Önder GURCAN (CEA LIST) and Maria POTOP-BUTUCARU 1

Fairness ? CryBlock 2019 2 Gewu BU

IOTA CryBlock 2019 3 Gewu BU

IOTA Bitcoin Miners CryBlock 2019 4 Gewu BU

IOTA Bitcoin Users Miners CryBlock 2019 5 Gewu BU

[1] IOTA-Tangle: a Transactions-DAG (DAG: Directed acyclic graph) CryBlock 2019 6 Gewu BU [1] Popov S. The tangle[J]. cit. on, 2016: 131.https://www.iota.org

[1] IOTA-Tangle: a Transactions-DAG (DAG: Directed acyclic graph) CryBlock 2019 7 Gewu BU [1] Popov S. The tangle[J]. cit. on, 2016: 131.https://www.iota.org

[1] IOTA-Tangle: a Transactions-DAG (DAG: Directed acyclic graph) CryBlock 2019 8 Gewu BU [1] Popov S. The tangle[J]. cit. on, 2016: 131.https://www.iota.org

[1] IOTA-Tangle: a Transactions-DAG (DAG: Directed acyclic graph) tips tips CryBlock 2019 9 Gewu BU [1] Popov S. The tangle[J]. cit. on, 2016: 131.https://www.iota.org

Tips selection Algorithm [1] (TSA) T3 T1 ? T5 T2 T4 CryBlock 2019 10 Gewu BU [1] Popov S. The tangle[J]. cit. on, 2016: 131.https://www.iota.org

[1] Level of Confidence Ta T3 T1 T5 Tb T2 T4 Tc CryBlock 2019 11 Gewu BU [1] Popov S. The tangle[J]. cit. on, 2016: 131.https://www.iota.org

[1] Level of Confidence Ta T3 25% 25% 25% T1 TSA = T5 T5 Tb Uniform 100% 25% T2 T4 25% Tc 75% CryBlock 2019 12 Gewu BU [1] Popov S. The tangle[J]. cit. on, 2016: 131.https://www.iota.org

[1] Conflicting Transactions 75% Ta T3 T1 T5 ? Tb T2 50% CryBlock 2019 13 Gewu BU [1] Popov S. The tangle[J]. cit. on, 2016: 131.https://www.iota.org

[1] Conflicting Transactions 75% Ta T3 T1 T5 Tb T2 50% CryBlock 2019 14 Gewu BU [1] Popov S. The tangle[J]. cit. on, 2016: 131.https://www.iota.org

[1] Weighted Random Walk TSA Fairness CryBlock 2019 15 Gewu BU [1] Popov S. The tangle[J]. cit. on, 2016: 131.https://www.iota.org

[1] Weighted Random Walk TSA 2 Cumulative 1 weight 4 2 CryBlock 2019 16 Gewu BU [1] Popov S. The tangle[J]. cit. on, 2016: 131.https://www.iota.org

[1] Weighted Random Walk TSA 3 10 8 2 1 7 4 10 6 2 5 3 Cumulative weight CryBlock 2019 17 Gewu BU [1] Popov S. The tangle[J]. cit. on, 2016: 131.https://www.iota.org

[1] Weighted Random Walk TSA 3 10 8 2 1 7 4 10 6 2 5 CryBlock 2019 18 Gewu BU [1] Popov S. The tangle[J]. cit. on, 2016: 131.https://www.iota.org

[1] Weighted Random Walk TSA 3 10 8 2 1 7 4 10 6 2 5 CryBlock 2019 19 Gewu BU [1] Popov S. The tangle[J]. cit. on, 2016: 131.https://www.iota.org

[1] Weighted Random Walk TSA 3 10 8 2 1 7 4 10 6 2 5 CryBlock 2019 20 Gewu BU [1] Popov S. The tangle[J]. cit. on, 2016: 131.https://www.iota.org

[1] Weighted Random Walk TSA 3 10 8 2 1 7 4 10 6 2 5 CryBlock 2019 21 Gewu BU [1] Popov S. The tangle[J]. cit. on, 2016: 131.https://www.iota.org

[1] Weighted Random Walk TSA 3 10 8 2 1 7 4 10 6 2 5 CryBlock 2019 22 Gewu BU [1] Popov S. The tangle[J]. cit. on, 2016: 131.https://www.iota.org

[1] Weighted Random Walk TSA 3 10 8 2 1 7 4 10 6 2 5 CryBlock 2019 23 Gewu BU [1] Popov S. The tangle[J]. cit. on, 2016: 131.https://www.iota.org

Rapidly Decaying parameter α [1] α -> Infinity To the next hop having the maximal CW α -> 0 Weighted Random Walk -> Unweighted Random Walk CryBlock 2019 24 Gewu BU [1] Popov S. The tangle[J]. cit. on, 2016: 131.https://www.iota.org

[1] Splitting attack Attacker Conflicting conflicting transactions transactions cumulative weight: 537 X cumulative weight: 541 CryBlock 2019 25 Gewu BU [1] Popov S. The tangle[J]. cit. on, 2016: 131.https://www.iota.org

Fairness issue An example of tangle with a relatively high α = 0.7. Many tips are left behind. CryBlock 2019 26 Gewu BU

Fairness issue An example of tangle with a relatively high α = 0.7. Many tips are left behind. CryBlock 2019 27 Gewu BU

Fairness issue Left-behind tips : tips who have not been approved for a time D_tips . Left-behind transactions : non-tips transactions who have not been confirmed for a time D_tran . CryBlock 2019 28 Gewu BU

Observation The confidence of a transaction is at least equal to the maximal confidence among all its son transactions. Tb C = 78% Tc C = 60% Ta C = 78% C = 40% Td CryBlock 2019 29 Gewu BU

G-IOTA CryBlock 2019 30 Gewu BU

G-IOTA future tips CryBlock 2019 31 Gewu BU

IOTA G-IOTA CryBlock 2019 32 Gewu BU

G-IOTA vs IOTA 100 1 75 0.75 50 0.50 25 0.25 0 CryBlock 2019 33 Gewu BU

Mutual Supervision Mechanism 1) What if a speculative user always verifies a third tips, a non-left- behind tips, to pretend that it works hard for helping the others? 2) What if a lazy user only chooses old conformed transactions to verify and pretends his transaction has been left-left-behind and waits others saving his transaction? check Sender neighbour Updating check Sender neighbour Rejecting / reporting CryBlock 2019 34 Gewu BU

G-IOTA has at lest the same security level than IOTA Formal proof Benefits of choosing the 3th tips Game theory CryBlock 2019 35 Gewu BU

G-IOTA: Fair and Confidence Aware Tangle IOTA Fairness G-IOTA CryBlock 2019 36 Gewu BU