The basic idea of reputation systems is to give users the possibility to rate the interactions that occur between them. Each user who purchased products from that seller had the opportunity to rate the purchase. In this way, all vendors that not provide adequate products received a bad reputation score . Currently, different marketplaces have been emerged focusing on the distribution of innovative solutions as a service, such as providing Virtual Network Functions-as-a-service (VNFaaS)  or Infrastructure-as-a-service (IaaS) to supply determined demands . However, in determined scenarios, centralized reputation mechanisms are not sufficient to provide trustworthy between customers and different vendors. In such a direction, decentralizing systems (e.g., blockchain-based reputation ) can be helpful by removing the possibility of any to delete, inflate or deflate reputation scores in order to serve their interests .
The goal of this thesis is to develop a blockchain-based reputation system that allows end-users to provide feedback regarding IaaS in order to create a trustworthy rank of different providers. The system's engine should support the creation of reputation systems with different information and purposes. Besides, mechanisms that allow the application of penalties in providers with misbehaviors should be investigated. Also, a web-based interface might be provided in order to simplify the interaction between the different actors involved.
 Viktor Jacynycz García: Towards a Decentralized Publication System: A Proposal Using Blockchain and P2P Technologies, Master's Thesis, Universidad Complutense de Madrid, 2018.
 L. Bondan, M. F. Franco, L. Marcuzzo, G. Venancio, R. L. Santos, R. J. Pfitscher, E. J. Scheid, B. Stiller, F. De Turck, E. P. Duarte, A. E. Schaeffer-Filho, C. R. P. Santos, and L. Z. Granville: FENDE: Marketplace-Based Distribution, Execution, and Life Cycle Management of VNFs; IEEE Communications Magazine, 57(1), January 2019, pp 1389-1406.
 Muriel Franco, Eder Scheid, Lisandro Granville, Burkhard Stiller: BRAIN: Blockchain-based Reverse Auction for Infrastructure Supply in Virtual Network Functions-as-a-Service; IFIP Networking 2019, Warshaw, Poland, 20-22 May 2019.
 Andreas Gruhler, Bruno Rodrigues, Burkhard Stiller: A Reputation and Reward Scheme for a Cooperative Network Defense; 16th IFIP/IEEE International Symposium on Integrated Network Management (IM 2019), April 2019, Washington DC, USA, pp. 1-8.
 aeternity, George Koynov: Could a Blockchain Based Reputation System Prevent a Dystopian Future?; https://hackernoon.com/could-a-blockchain-based-reputation-system-prevent-a-dystopian-future-d58522b88e2c, last visit July 2019.
Supervisors: Muriel Figueredo Francoback to the main page