SONET STS Use the SONET STS subtab to provision the SONET STS line for the EC1-12 card (ONS 15454 only) and ports. Item Description STS # Displays the STS number. Enable IPPM Enables the intermediate path performance monitoring (IPPM). Apply Applies changes made to the fields in the tab. Reset Cancels any changes to the tab and returns the fields to their last-saved settings. Help Displays context-sensitive help.