Subdomain and main site

Hi i had purchased Securitycheck Pro for my main site i like to know if i have created a sub-domain eg www.mysite.com/training do i need to also install Securitycheck Pro on my sub-domain to protect it from online threat or the main site Securitycheck Pro installation will also protect my sub-domain.

Thank you in advance

Its awesome and more intelligent then my cooperate firewall which is really dumb thank you for creating this extension will continue to subscribe