id-consensus.md

title
-chap-num- Consensus

import Pseudocode from '@site/src/components/Pseudocode'; import epochRandomness from '!!raw-loader!@site/src/algorithms/epochRandomness.tex';

-sec-num- BABE digest messages {#id-babe-digest-messages}

The Runtime is required to provide the BABE authority list and randomness to the host via a consensus message in the header of the first block of each epoch.

The digest published in Epoch ${\mathcal{{{E}}}}{{n}}$ is enacted in ${\mathcal{{{E}}}}{{{n}+{1}}}$. The randomness in this digest is computed based on all the VRF outputs up to including Epoch ${\mathcal{{{E}}}}{{{n}-{2}}}$ while the authority set is based on all transaction included up to Epoch ${\mathcal{{{E}}}}{{{n}-{1}}}$.

The computation of the randomness seed is described in Epoch-Randomness, which uses the concept of epoch subchain as described in host specification and the value ${d}{{B}}$, which is the VRF output computed for slot ${s}{{B}}$.

Algorithm -algo-num- Epoch Randomness {#algo-epoch-randomness}

:::algorithm <Pseudocode content={epochRandomness} algID="epochRandomness" options={{ "lineNumber": true }} />

where ${n}$ is the epoch index. :::