Fortinet FCSS_EFW_AD-7.6 Dumps Questions Answers

The Internet Service Database (ISDB) in FortiGate is used to enforce content filtering at Layer 3 (Network Layer) and Layer 4 (Transport Layer) of the OSI model by identifying applications based on their predefined IP addresses and ports.

FortiGate has a predefined list of all IPs and ports for specific applications downloaded from FortiGuard:

● FortiGate retrieves and updates a predefined list of IPs and ports for different internet services from FortiGuard.

● This allows FortiGate to block specific services at Layer 3 and Layer 4 without requiring deep packet inspection.

The ISDB blocks the IP addresses and ports of an application predefined by FortiGuard:

● ISDB works by matching traffic to known IP addresses and ports of categorized services.

● When an application or service is blocked, FortiGate prevents communication by denying traffic based on its destination IP and port number.

When configuring ADVPN (Auto-Discovery VPN) to connect overlay networks across different hubs using IBGP and EBGP, special configurations are required to allow spokes from different overlay networks to dynamically establish tunnels.

● set auto-discovery-crossover enable

● This allows cross-hub tunnel discovery in an ADVPN deployment where multiple hubs are used.

● Since Hub A and Hub B belong to different overlays, enabling crossover discovery ensures that spokes from one overlay can dynamically create direct tunnels to spokes in the other overlay when needed.

● set enforce-multihop enable

● This setting ensures that BGP peers using loopback interfaces can establish connectivity even if they are not directly connected.

● Multihop BGP sessions are required when using loopback addresses as BGP peer sources because the connection might need to traverse multiple routers before reaching the BGP neighbor.

● This is especially useful in ADVPN deployments with multiple hubs, where routes might need to cross from one hub to another.

In an ADVPN (Auto-Discovery VPN) network, a dynamic VPN tunnel is established on-demand between spokes to optimize traffic flow and reduce latency.

Process:

1. Traffic Initiation:

A client behind Spoke-1 sends traffic to a device behind Spoke-2.

The traffic initially flows through the hub, following the pre-established overlay tunnel.

2. Hub Detection:

The hub detects that Spoke-1 is communicating with Spoke-2 and determines that a direct shortcut tunnel between the spokes can optimize the connection.

3. Shortcut Offer:

The hub sends a "Shortcut Offer" message to Spoke-1, informing it that a direct dynamic tunnel to Spoke-2 is possible.

4. Tunnel Establishment:

Spoke-1 and Spoke-2 then negotiate and establish a direct IPsec tunnel for communication.