When you create your own APT repo, you have to create a GPG key for it. So you need to import it with:
apt-key add yourkey.asc
or with a key server:
apt-key adv --keyserver keyserver.ubuntu.com --recv 3E5C1192
However, I do not know any update process for this ? When the key will expire, in both case, do we need to import-it again ?
