DCC Web Application is a java based web application designed to control locos and accessories using a web interface. The application also opens up rest interfaces for block detection can call external interfaces to set relays.
Macros can be setup to run sequences of dcc commands, these macros can be set to be triggered on events. So when a block changes from unoccupied to occupied this can trigger a signal to change from proceed to stop which in turn can trigger a macro to run to set a relay that controls a section of line to a asymetrical signal to initiate breaking.