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lan

Networking for
Architects

You don't need to be a network engineer, but you must know how data moves. TCP handshakes, DNS propagation, and protocol overheads define your system's boundaries.

The Stack (Simplified)

L7 ApplicationHTTP, DNS, SSH. What your code talks to.
L4 TransportTCP, UDP. Reliability and ports.
L3 NetworkIP. Routing packets across the internet.
L2 Data LinkEthernet, Wi-Fi. Moving frames between devices.

"As an architect, you mostly live in L7, optimize in L4, and pray L3 works."

TCP vs UDP

TCP

Transmission Control Protocol

  • ✓ Reliable (ACKs)
  • ✓ Ordered delivery
  • ✓ Congestion control
  • ✗ Slower (Handshakes)
Use for: Web, Email, File Transfer, DBs

UDP

User Datagram Protocol

  • ✓ Fast (Fire & Forget)
  • ✓ Low overhead
  • ✗ Unreliable (Packet loss)
  • ✗ Out of order
Use for: Gaming, VoIP, Streaming, DNS

HTTP Evolution

1

HTTP/1.1

Legacy but everywhere

Text-based. One request per connection (HOL Blocking). Keep-alive added later.

2

HTTP/2

Modern standard

Binary. Multiplexing (many requests, one connection). Header compression (HPACK).

3

HTTP/3

Bleeding edge / Mobile

QUIC (UDP-based). No HOL blocking at packet level. Built-in encryption.

gRPC & Protobuf

code

Why use it over REST?

Pros

  • • Binary (Protobuf) is much smaller than JSON
  • • Strongly typed contracts (.proto)
  • • Auto-generated client/server code
  • • Built on HTTP/2 (streaming support)

Cons

  • • Not human readable (needs tools)
  • • Browser support requires proxy (gRPC-Web)
  • • Steeper learning curve than REST