Check that all accounts have passwords assigned to them. If any accounts don t have passwords, either disable the account, or assign a password to it. While these extra services may be necessary for your configuration, they also provide the outside with additional ways in. Many package work to provide security options. Time and testing must be used to secure the services.
Logs can provide a wonderful source of information when looking for signs of attacks.
Know what services are keeping logs are review them on a weekly basis. Look for repeated login attempts from unknown domains, remove all guest accounts. If you use mail, make sure that any relay options are turned off. These systems are used by spammers and blackballed by system administrators worldwide. Enjoy your high-speed connection.