It could just be a GUID. The community’s host instance assigns a GUID (which by definition is unique in all GUIDs) and then when sending the post or comment out to federate to other servers it includes the GUID for the other instances to use.
I don’t think there’s a need for a GUID, in fact it would be quite difficult - every instance would have to check with every other instance to ensure that the ID’s are unique. Meanwhile, if we just have the federated host picking a number, then every other host uses that number followed by @hostinstance, we don’t need cross-checking but still have unique ID’s for everything.
For example, https://lemm.ee/comment/123456 would be a different comment to https://lemmy.nz/comment/123456 (as it is currently also), but the first comment could be found on the 2nd instance as https://lemmy.nz/comment/123456@lemm.ee.
It could just be a GUID. The community’s host instance assigns a GUID (which by definition is unique in all GUIDs) and then when sending the post or comment out to federate to other servers it includes the GUID for the other instances to use.
I’m a massive fan of GUIDs, too, but you’d have no protection from rogue instances reusing GUIDs of existing posts…
I don’t think there’s a need for a GUID, in fact it would be quite difficult - every instance would have to check with every other instance to ensure that the ID’s are unique. Meanwhile, if we just have the federated host picking a number, then every other host uses that number followed by
@hostinstance, we don’t need cross-checking but still have unique ID’s for everything.For example,
https://lemm.ee/comment/123456would be a different comment tohttps://lemmy.nz/comment/123456(as it is currently also), but the first comment could be found on the 2nd instance ashttps://lemmy.nz/comment/123456@lemm.ee.