# kaal:claim:3125827-030

**Claim.** A 67% active validator requirement would improve finality but is excluded from the initial SPoS implementation because, by the CAP theorem, it limits the availability of the system and arbitrarily punishes randomly selected producers when the network is partitioned.

**Type.** failure  **Support.** argued

**Holds when.**

- network partitions occur
- consensus recognizes only blocks validated by a supermajority of active validators

**Source quote.**

> More importantly, due to the CAP theorem33, it limits the availability of the system, which is why it is not included in the initial implementation.

**From.** Craig Calcaterra, Wulf A. Kaal, *Secure Proof of Stake Protocol* (2018), 5.2 Block production, page 21

**Cite as.** Craig Calcaterra, Wulf A. Kaal, Secure Proof of Stake Protocol (2018). SSRN: https://ssrn.com/abstract=3125827

**Verify.** sha256 of source PDF `598d9bd95e4af7a0a35328677c6bfc069f69f2e32c30c720b3a0be98a23a40cb` at https://raw.githubusercontent.com/wulfkaal/Academic-Papers/main/papers/pdf/Calcaterra%20and%20Kaal%20-%202018%20-%20Secure%20Proof%20of%20Stake%20Protocol.pdf

**Failure mode.** supermajority-validator-requirement-cost  (family: scalability-and-throughput-limit)

**Topics.** institutional-design

**Keywords.** cap-theorem, availability, finality, network-partition, parameter-choice

**Canonical form.** This markdown file is the canonical hashed representation of the claim. Its sha256 is the content hash used for attestation.