--- /dev/null
+At a few places, it is necessary for '''HCOOP members''' to authenticate to HCOOP -\r
+either to gain initial access or use additional authenticated services.\r
+\r
+= Authentication barriers =\r
+\r
+|| '''Instance''' || '''Controlling subsystem''' || '''HCOOP interface''' || '''Type of access''' || '''Full user control''' ||\r
+|| SSH || OpenSSH internals or PAM || `passwd`, `chfn`, `chage`, `chsh` || Remote, local || No ||\r
+|| FTP || PAM || `passwd` || Remote, local || No ||\r
+|| HCOOP Web portal || HTTP Digest Authentication || `webpasswd` || Remote, local || Yes ||\r
+|| Databases || Database-specific access tables || `dbtool` || Local || Yes ||\r
+|| Firewall || IPTables/Netfilter || `fwtool` || Remote, local || No ||\r