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Network Topology

Visualizing how packets traverse Autonomous Systems (AS) via BGP. Understanding the mesh nature of the global internet.

TCP 3-Way Handshake

Client
SYN
SYN-ACK
ACK
Server

Common Ports Registry

SSH
22
Secure Shell
DNS
53
UDP/TCP Lookup
HTTP
80
Web Traffic
HTTPS
443
TLS / QUIC
FTP
21
File Transfer
RDP
3389
Remote Desk

Chain of Trust

Root CA
ISRG Root X1
Self-Signed
Intermediate
R10 / R11
Signed by Root
Leaf Certificate
*.domain.com
Your Domain

IPv4 vs IPv6 Address Space

IPv4 (32-bit) Exhausted
4.3 Billion Addresses
100% Used
IPv6 (128-bit) Infinite
3.4 × 10³⁸ Addresses
~0% Used
Example: 2001:0db8:85a3:0000:0000:8a2e:0370:7334
HTTP/3 UDP

QUIC Protocol

Multiplexed connections over UDP. Eliminates Head-of-Line blocking found in TCP. Essential for low-latency modern web applications.

Handshake Latency 0-RTT / 1-RTT
Packet Loss Recovery Stream Independant