Protocol Alpha#

This page lists the changes brought by protocol Alpha with respect to Tallinn (see Protocol changes). For the list of changes brought by Tallinn with respect to Seoul, see Protocol Tallinn.

For a higher-level overview of the most salient new features see the announcement blog.

An overview of breaking changes and deprecations introduced in protocol Alpha can be found here. These changes are also listed below in their respective topical section, tagged with Breaking change or Deprecation.

The code is available in directory src/proto_alpha of the master branch of Octez and the full documentation in this page.

Environment Version#

Smart Rollups#

The rollup now validates imported DAL pages using the DAL parameters that were active at the time of publication. This aligns rollup validation with the protocol rules when DAL parameters change across protocol versions. (MR !20402)

Consensus#

Implemented a new algorithm for the baker selection. The current Alias method is used to determine the validator that should bake a block for a given level and round. After the feature flag swrr_new_baker_lottery_enable is activated, the selection would use SWRR (Smooth Weighted Round Robin), which is a deterministic method to distribute the round 0 of all the levels for a given cycle. The higher rounds are then using a shifted version of this list. This method still remains proportional to the stake of the baker, and aims to reduce variability of block distribution, especially for small bakers. (MR !20084)

Data Availability Layer#

Introduced a new format for the bitset representing baker-attested DAL slots, used in the DAL payload of consensus attestation operation, and protocol-attested DAL slots, used in a block metadata’s field "dal_attestation". The format is described in the header of the file src/proto_alpha/lib_protocol/dal_attestations_repr.mli. (MR !20734) and (MR !20731)
Increase number of slots to 160. (MR !20457)
Increase slot size to 380_832 bytes. (MR !20457)
Introduced a new optional field lag_index to DAL entrapment evidence operations. (MR !20360)

Adaptive Issuance#

Gas improvements#

Breaking Changes#

RPC Changes#

Operation receipts#

Errors#

Protocol parameters#

Feature flags#

Added native_contracts_enable, that enables enshrined contracts in the protocol. The flag is disabled by default on the mainnet. (MR !19709)
Added tz5_account_enable, that enables tz5 ML-DSA-44 account support in the protocol. The flag is disabled by default on the mainnet. (MR !20680)

Cryptography#

Support for ML-DSA-44 signatures and introduction of a new account type whose address has the prefix tz5 (whose keys are ML-DSA-44 key pairs). In the protocol, tz5 accounts are under a feature flag tz5_account_enable, which is disabled by default on the mainnet. On testing networks where this feature flag is enabled, tz5 accounts cannot be registered as delegates, and tz5 keys cannot be used as consensus keys. (MRs !20251, !20680)

Protocol Alpha

Contents