The purpose of the Switch Microservice of Policy Enforcer is to isolate infected hosts. The Switch Microservice is a component of Policy Enforcer that runs on EX Series and QFX Series switches. It communicates with Policy Enforcer and Juniper ATP Cloud to receive threat intelligence and quarantine commands. When an infected host is detected by Juniper ATP Cloud, Policy Enforcer sends a command to the Switch Microservice to isolate the host by applying an access control list (ACL) on the switch port where the host is connected. The ACL blocks all traffic from or to the host except for the traffic that is required for remediation. The Switch Microservice also tracks the MAC address of the infected host and updates Policy Enforcer if the host moves to a different switch port or a different switch. This way, the Switch Microservice ensures that the infected host is isolated until it is remediated and no longer poses a threat to the network. References: Juniper Security, Professional (JNCIP-SEC) Reference Materials source and documents: https://www.juniper.net/documentation/en_US/junos/topics/concept/security-policy-enforcer-switch-microservice-overview.html