CAIP-13 - Blockchain Reference for Polkadot Namespace

[pedrouid]

As pointed out from this PR https://github.com/ceramicnetwork/specs/pull/12, there is no standard way currently to reference polkadot chains so I thought it would be best to start a discussion for a new CAIP to tackle this.

From the suggestion of @joshua-mir and @shawntabrizi on the PR mentioned above, the best way to reference Polkadot chains would be to use the genesis-hash similar to how Bitcoin namespace uses BIP122 as a reference for chainId.

I will start a draft for this proposal using CAIP-4 as a template.

[pedrouid]

There is an issue however with using the genesis-hash as is to be compatible with CAIP-2 since the reference should not be longer than 47 characters.

# Kusama
polkadot:b0a8d493285c2df73290dfb7e61f870f17b41801197a149ca93654499ea3dafe
# Edgeware
polkadot:742a2ca70c2fda6cee4f8df98d64c4c670a052d9568058982dad9d5a7a135c5b
# Kulupu
polkadot:37e1f8125397a98630013a4dff89b54cb758ff8eed894419e65a6dcf27a6fb8a

In that case I would suggest that we truncate it to 47 characters or we would use the first 32 characters from the resulting hash.

I would love your feedback. cc @webmaster128 @ligi

[shawntabrizi]

@pedrouid this sounds like a good approach from our side!

Although polkadot:hash may not be as generic as substrate:hash. There may be many future substrate chains not related to Polkadot, but could enter your ecosystem for free because they all follow the same standards.

[ligi]

I like the more generic substrate: idea - could help in the future. Otherwise LGTM

[jam10o-new]

would actually argue counter to that - substrate is exclusive to alternative Polkadot Hosts (Gossamer, Kagome) or parachain development kits (none exist yet afaik but 🤷‍♂️) which would connect to the same networks but might not use Substrate at any stage.

polkadot is the name of the chain, but also the name of the network.

[pedrouid]

Yeah this is similar to cosmos namespace where we argued about using tendermint instead but you can be part of the cosmos network and not use tendermint so I would keep it as polkadot

[pedrouid]

Actually I just realized that CAIP-4 uses the first 32 characters of the genesis hash, I will update to match it

[pedrouid]

I've updated the PR #14... please give it another look @joshua-mir @shawntabrizi @ligi before merging

[pedrouid]

Merged #14

[imsys]

I think it could be nice to add the hash of Polkadot Mainnet to the list. Just for reference and to help others implementing the CAIP standards.

# Polkadot mainnet
polkadot:91b171bb158e2d3848fa23a9f1c25182

Source: https://polkadot.subscan.io/block/0

[uddyami]

how do i find caip-13 id for rococo testnet?