Permissioned Blockchains and Distributed Databases : A Performance Study

Abstract: Blockchain technology is a booming new field in both computer science and economicsand other use cases than cryptocurrencies are on the rise. Permissioned blockchains are oneinstance of the blockchain technique. In a permissioned blockchain the nodes which validatesnew transactions are trusted. Permissioned blockchains and distributed databasesare essentially two different ways for storing data, but how do they compare in terms ofperformance? This thesis compares Hyperledger Fabric to Apache Cassandra in four experimentsto investigate their insert and read latency. The experiments are executed usingDocker on an Azure virtual machine and the studied systems consist of up to 20 logicalnodes. Latency measurements are performed using varying network size and load. Forsmall networks, the insert latency of Cassandra is twice as high as that of Fabric, whereasfor larger networks Fabric has almost twice as high insert latencies as Cassandra. Fabrichas around 40 ms latency for reading data and Cassandra between 150 ms to 250 ms, thusit scales better for reading. The insert latency of different workloads is heavily affected bythe configuration of Fabric and by the Docker overhead for Cassandra. The read latency isnot affected by different workloads for either system.