The CA SystemEDGE Service (sysedge.exe) and CA Message Queueing Server (cam.exe) services are the only two services which need to be running for SystemEDGE to operate.
If SystemEDGE is installed using the LEGACY_MODE parameter then CA Message Queuing Server Service is not installed\required.
SystemEDGE leverages CAM when in managed mode for communication with VAIM.