As per the standing orders that will be implemented at the opening of a new Parliament, petitions can only be signed by either a Canadian resident or a Canadian citizen living abroad. People will need to indicate or confirm by self-declaration that they are either living in Canada or Canadians living abroad. That will be part of the terms of use.
Evidence of meeting #83 for Procedure and House Affairs in the 41st Parliament, 2nd Session. (The original version is on Parliament’s site, as are the minutes.) The winning word was petition.
A recording is available from Parliament.