mirror of
https://github.com/logos-messaging/specs.git
synced 2026-01-02 22:23:07 +00:00
60 lines
2.7 KiB
Markdown
60 lines
2.7 KiB
Markdown
---
|
||
title: WAKU-STORE-SYNC
|
||
name: Waku Store Synchronization
|
||
editor: Simon-Pierre Vivier <simvivier@status.im>
|
||
contributors:
|
||
---
|
||
|
||
## Abstract
|
||
|
||
This document describe the strategy Waku Store node will employ to stay synchronized.
|
||
The goal being that all store nodes eventually archive the same set of messages.
|
||
|
||
## Background / Rationale / Motivation
|
||
|
||
Message propagation in the network is not perfect,
|
||
even with GossipSub mechanisms to detect missed messages.
|
||
Nodes can also go offline for various reason outside our control.
|
||
Store nodes that want to provide a good service must be able to remedy situations like these.
|
||
By having store nodes syncronize with each other through various protocols,
|
||
the set of archived messages network wide will be eventually consistent.
|
||
|
||
## Theory / Semantics
|
||
|
||
The key words “MUST”, “MUST NOT”, “REQUIRED”, “SHALL”, “SHALL NOT”, “SHOULD”, “SHOULD NOT”, “RECOMMENDED”, “NOT RECOMMENDED”, “MAY”, and “OPTIONAL” in this document are to be interpreted as described in [RFC 2119](https://www.ietf.org/rfc/rfc2119.txt).
|
||
|
||
Various protocols and features that help with message consistency are described below.
|
||
|
||
### Store Resume
|
||
|
||
<!-- restating this as a heuristic rather than a high-level description of functionality allows the spec to be useful for new implementers -->
|
||
|
||
This feature allow a node to fill the gap in messages for the period it was last offline.
|
||
At startup, a node use the Store protocol to query a random node for
|
||
the time interval since it was last online.
|
||
Messages returned by the query are then added to the node local archive storage.
|
||
It is RECOMMENDED to limit the time interval to a maximum of 6 hours.
|
||
|
||
### Waku Sync
|
||
|
||
<!--
|
||
For the new version. "think of a specification as a heuristic/set of directives that almost form a kind of pseudocode. This becomes easier if you use the RFC keywords for each directive"
|
||
-->
|
||
|
||
Nodes that stay online can still miss messages.
|
||
[Waku Sync](https://github.com/waku-org/specs/blob/master/standards/core/sync.md) is the protocol used to find those message hashes by periodically syncing with random nodes.
|
||
It is RECOMMENDED to trigger a sync with a random peer every 5 minutes for a time range of the last hour.
|
||
After both message hash sets are reconciled,
|
||
the Store protocol SHOULD be used to reciprocally query the other node with the message hash differences found.
|
||
Messages returned by the query MUST be added to the node local Waku sync and archive storage.
|
||
|
||
<!-- TODO add the number of node to sync with -->
|
||
|
||
## Copyright
|
||
|
||
Copyright and related rights waived via [CC0](https://creativecommons.org/publicdomain/zero/1.0/).
|
||
|
||
|
||
## References
|
||
|
||
- [Waku Sync](https://github.com/waku-org/specs/blob/master/standards/core/sync.md) |