The Shutdown Problem: How Does a Blockchain System End?

Understand

We define and examine the shutdown problem for blockchain systems: how to gracefully end the system's operation at the end of its useful life.

• A particular focus is those blockchain systems that hold archival data of long-lived interest.
• We outline what it means to achieve a successful shutdown, and compare those criteria to likely end-of-life conditions in a generic blockchain system.
• We conclude that the decentralized nature of blockchain systems makes shutdown difficult, particularly if the system uses an unstable consensus like the Nakamoto consensus of Bitcoin.