NSX API: This is a RESTful API that allows you to programmatically configure and manage Distributed Firewall on VDS using HTTP methods and JSON payloads. You can use tools such as Postman or curl to send API requests to the NSX Manager node.
NSX UI: This is a graphical user interface that allows you to configure and manage Distributed Firewall on VDS using menus, tabs, buttons, and forms. You can access the NSX UI by logging in to the NSX Manager node using a web browser.
https://docs.vmware.com/en/VMware-NSX/4.1/administration/GUID-0DEF9F18-608D-4B5C-9175-5514750E901B.html

The main components on the edge node for north-south malware prevention perform the following functions:
- IDS/IPS engine: Extracts files and relays events and data to the security hub North-south malware prevention uses the file extraction features of the IDS/IPS engine that runs on NSX Edge for north-south traffic.
- Security hub: Collects file events, obtains verdicts for known files, sends files for local and cloud- based analysis, and sends information to the security analyzer
- RAPID: Provides local analysis of the file

When two virtual machines are connected on the same overlay segment, they are part of the same Layer 2 broadcast domain. In this case, the communication between the two VMs is happening within the same broadcast domain, which means that broadcast traffic can be sent to all devices on the segment. Since the ping is successful, the two VMs can communicate directly over Layer 2 without needing routing.

Quarantine workloads based on vulnerabilities: You can use Distributed Intrusion Detection to detect vulnerabilities in your workloads and apply quarantine actions to isolate them from the network until they are remediated.
Identify security vulnerabilities in the workloads: You can use Distributed Intrusion Detection to scan your workloads for known vulnerabilities and generate reports that show the severity, impact, and remediation steps for each vulnerability.

Virtual Tunnel Interfaces (VTI) are used in route-based VPNs. In this type of VPN, the tunnel is treated like a regular interface on the router. This allows for the configuration of routing protocols and the application of routing decisions to the traffic flowing through the VPN tunnel. VTIs simplify the management of routing and make it more flexible in VPN scenarios.