There are two parties that suffer from spam: the relay and the group members.
In Bitchat’s Geohash open and permissionless channels, it is mainly the group members who suffer from spam, since the relay can quickly delete messages and is therefore less affected.
In contrast, Keychat’s end-to-end encrypted group chat is closed and permissioned: the group owner can add or remove members, and only group members can read and send messages.
As a result, Keychat group members do not suffer from spam. Moreover, because Keychat messages carry an ecash sat stamp, the relay also does not suffer from spam.
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