I am working on a development machine and I am trying to connect to my LDAP server. This is what I do - telnet ldaps- 686 then the response is - Could not open connection to the host on port 686 : connect failed But, the strange part is when I connect to my server - telnet ldap- 389 then the connection is successful. My question is, why does this happen? Do I have to install SSL certificate on the client machine where I make the call from? I do not know much about this. I know for a fact that the LDAP server is working fine because other applications are successfully using it currently.