Hi Yamini,

We can check the IP address as mentioned here,
https://success.outsystems.com/support/enterprise_customers/maintenance_and_operations/find_out_internal_ip_address_range_of_your_outsystems_cloud/

Hi @Yamini Pandya,

These terms are referred to the services that are running in the background and each service is dedicated for specific purpose. Like here in below image
you can see each service has one source that is frontend server and there are some services which are on controller server which generally controls all the deployment related operations in OS. 

Or Maybe you can look at these that will give you more clarity about these

That is as per my understanding.
Thanks