Selman Erol

Longest-chain Attacks: Difficulty Adjustment and Timestamp Verifiability

2023 · arXiv (Cornell University)

We study an adversary who attacks a Proof-of-Work (POW) blockchain by selfishly constructing an alternative longest chain. We characterize optimal strategies employed by the adversary when a difficulty adjustment rule alà Bitcoin applies. As time …

Poster: Timestamp Verifiability in Proof-of-Work

2023

Various blockchain systems have been designed for dynamic networked systems. Due to the nature of the systems, the notion of "time" in such systems is somewhat subjective; hence, it is important to understand how the …