The strength of any chain is only as strong as its weakest link.

While a useful term in the industries that work with an actual chain1, the analogy can also be expanded to composite (digital) systems with interdependent constituents.

Strong Link Weak Link Strong Link

The argument then is that the overall Trustless-ness of a composite Authority is only as good as its weakest component.

Few examples of this concept that we see in this book:

  • Oracle Problem, especially when bridging real-world information to the blockchain.
  • Scaling Out - Pure Multi-chain, where an interconnected set of blockchains with different degrees of Economic Security exchanges value-bearing messages, and act upon them, not taking into account that the sending chain of a message might be compromised.

Footnotes

  1. Originally appearing in “Essays on the Intellectual Powers of Man”.