Trace the Path: Server to User

When you click a link, a miracle of coordination occurs. Let's trace a packet from an AWS server in Virginia to a phone in London.

1. Application Processing: The web server generates HTML. It hands the data to the Kernel.
2. Encapsulation: The kernel wraps data in TCP headers (Port 443), then IP headers (Dest IP).
3. VPC Routing: The packet leaves the virtual NIC. The SDN controller checks the VPC Route Table. It sees "0.0.0.0/0 -> Internet Gateway".
4. The Cloud Backbone: The packet traverses AWS's fiber from the DC to the Edge PoP in Ashburn.
5. Peering Point (The Handshake): AWS hands the packet to a Transatlantic Carrier (like Level3 or Telia) at an Internet Exchange Point (IXP).
6. Under the Ocean: The packet travels through a submarine cable at 99% the speed of light in glass.
7. ISP Handoff: In London, the carrier hands off to "British Telecom" (the user's ISP).
8. The Last Mile: BT routes it to the street cabinet, then copper/fiber to the house router.
9. WiFi: The router broadcasts radio waves. The phone antenna catches them.
10. Decapsulation: The phone strips the headers and renders the HTML. Time taken: 80ms.