How stable are the subnet ranges for canister IDs?

[Severin]

@roben0010

How frequently do these assignments change?

So far we had a single canister change subnets ever. You can read more about it here.

@roben0010

If canister subnet migrations were to be introduced in the future, how might that impact the stability of subnet-to-canister ID ranges?

Obviously that would mean that canister id ranges can change. Depending on the implementation that would be more or less often

@roben0010

Currently, a canister cannot determine another canister’s subnet on the Internet Computer without making an HTTP outcall to the IC API.

It is already exposed on chain: The registry has an endpoint that will tell you which subnet a certain canister ID belongs to (no matter if the canister actually exists or not)