8,332 research outputs found
An Alloy Verification Model for Consensus-Based Auction Protocols
Max Consensus-based Auction (MCA) protocols are an elegant approach to
establish conflict-free distributed allocations in a wide range of network
utility maximization problems. A set of agents independently bid on a set of
items, and exchange their bids with their first hop-neighbors for a distributed
(max-consensus) winner determination. The use of MCA protocols was proposed,
, to solve the task allocation problem for a fleet of unmanned aerial
vehicles, in smart grids, or in distributed virtual network management
applications. Misconfigured or malicious agents participating in a MCA, or an
incorrect instantiation of policies can lead to oscillations of the protocol,
causing, , Service Level Agreement (SLA) violations.
In this paper, we propose a formal, machine-readable, Max-Consensus Auction
model, encoded in the Alloy lightweight modeling language. The model consists
of a network of agents applying the MCA mechanisms, instantiated with
potentially different policies, and a set of predicates to analyze its
convergence properties. We were able to verify that MCA is not resilient
against rebidding attacks, and that the protocol fails (to achieve a
conflict-free resource allocation) for some specific combinations of policies.
Our model can be used to verify, with a "push-button" analysis, the convergence
of the MCA mechanism to a conflict-free allocation of a wide range of policy
instantiations
Towards Secure Blockchain-enabled Internet of Vehicles: Optimizing Consensus Management Using Reputation and Contract Theory
In Internet of Vehicles (IoV), data sharing among vehicles is essential to
improve driving safety and enhance vehicular services. To ensure data sharing
security and traceability, highefficiency Delegated Proof-of-Stake consensus
scheme as a hard security solution is utilized to establish blockchain-enabled
IoV (BIoV). However, as miners are selected from miner candidates by
stake-based voting, it is difficult to defend against voting collusion between
the candidates and compromised high-stake vehicles, which introduces serious
security challenges to the BIoV. To address such challenges, we propose a soft
security enhancement solution including two stages: (i) miner selection and
(ii) block verification. In the first stage, a reputation-based voting scheme
for the blockchain is proposed to ensure secure miner selection. This scheme
evaluates candidates' reputation by using both historical interactions and
recommended opinions from other vehicles. The candidates with high reputation
are selected to be active miners and standby miners. In the second stage, to
prevent internal collusion among the active miners, a newly generated block is
further verified and audited by the standby miners. To incentivize the standby
miners to participate in block verification, we formulate interactions between
the active miners and the standby miners by using contract theory, which takes
block verification security and delay into consideration. Numerical results
based on a real-world dataset indicate that our schemes are secure and
efficient for data sharing in BIoV.Comment: 12 pages, submitted for possible journal publicatio
Identifying malicious nodes in network-coding-based peer-to-peer streaming networks
published or submitted for publicatio
- …