To be able to use the forums you need to sign up in the Wiki, or login, if you have already signed up (menu on the top right).
For the forum, you use the same login data as for the Wiki. When you visit the forum for the first time, you need to confirm your data once. Your data will then be recognized automatically whenever you visit the forum again and have already logged into the Wiki. Of course, this also applies in reverse direction, i.e. if you have already logged into the forum and call the Wiki from there.
The direct Internet address of the forum is https://forum.isdgroup.com/.