Packet Journey.

This is a fictional network. It never scans or sends requests to real targets. Addresses are examples, and the glowing parcel represents a flow of many packets. We show a fresh DNS lookup and HTTPS over TCP, with a valid certificate and a stateful firewall. DNS and the public control website have existing allow rules; resolver configuration can still fail. In the advanced cases, the Internet icon represents the public path to a work VPN gateway. The private portal is behind that gateway. The model assumes approved credentials and successful VPN authentication. Real networks also use caches, many intermediate routers, address translation, retransmissions, and other transports such as HTTP/3 over QUIC.

The practice firewall is deliberately restrictive so you can see how one scoped rule works; this is not a recommendation to manually configure every website on a home router.

Open the lightweight diagram version (no 3D graphics needed).

• NIST: Remote access and VPN security
• MDN: How the Internet works
• MDN: Transport Layer Security
• IANA: HTTPS and port 443
• NIST: Firewalls and firewall policy