Using Homomorphic hashes in coded blockchains
This work addresses scalability and security issues for blockchain users and developers, but it is incremental as it builds on existing coded blockchain concepts.
The paper tackles the problem of malicious nodes propagating erroneous coded fragments in coded blockchains, which can hinder scalability and decentralization, by proposing the integration of homomorphic hashes to enable instantaneous detection of such errors and prevent incorrect decoding.
One of the scalability issues of blockchains is the increase of their sizes which can prevent users from storing them and thus from contributing to the decentralization effort. Recent works developed the concept of coded blockchains, which allow users to store only some coded fragments of the blockchains. However, this solution is not protected against malicious nodes that can propagate erroneous coded fragments. We propose in the paper to add homomorphic hashes to this system. This allows for instantaneous detection of erroneous fragments and thus avoids decoding with wrong data. We describe the integration of this mechanism in coded blockchains and we evaluate its complexity theoretically and by simulation.