SEP connection problem

Hi

I need some guidance. Our company has some clients that are out of domain and I can't force them to connect to sepm server. Can You explain me is it possible to see non domain clients inside SEPM manager? If yes ( I suppose) where can be a problem? So far now I ve checked connection from clients to server - port 8014 is opened and server answers for http://xxx:8014/secars/secars.dll?hello,secars. On client side I see connection 503 http error.

My suspicion make sylink.hml file

1) If inside is defined DomianID is there a chance for non domain clients to connect?

2) Is there maybe some sort of certificate problem?

3) Is standalone install any solution for problem?

Please be patient I wasn't present when SEPM was introduced for my company.