I have a environment where security of OPC provided data is not really of concern. One station should read some data via OPC from another PC.
To simplify things with user accounts, domains, and all that other nasty security stuff, I like to make the OPC server component running on the "server" side as wide open as possible - means everybody with a windows machine who is able to ping that server should be able to read those provided data values with an appropriate client software.
Think of it as temperature and stocked amount of the coke vending machine - interesting to all, but not of security concern.
What do I need to do to rip such a security hole into the server ?