All topics

Computer Networks

Layer by layer, from the wire up to HTTP

36 chapters across 8 modules
1

Foundations of Networking

5 chapters

1

What a Network Is and Why Layers

6 min read

2

The OSI and TCP/IP Models

6 min read

3

Encapsulation

7 min read

4

Network Types and Topologies

7 min read

5

Measuring a Network

8 min read

2

Physical and Data Link Layers

4 chapters

1

Signals, Media and Bandwidth

8 min read

2

Framing and Error Detection

8 min read

3

MAC Addressing and Ethernet

8 min read

4

Switching, ARP and VLANs

9 min read

3

The Network Layer

5 chapters

1

IP Addressing and Subnetting

7 min read

2

IPv4, IPv6 and Address Exhaustion

8 min read

3

Routing Fundamentals

8 min read

4

Routing Algorithms

9 min read

5

NAT, DHCP and ICMP

9 min read

4

The Transport Layer

5 chapters

1

Ports, Sockets and Multiplexing

8 min read

2

UDP

7 min read

3

TCP Connections and Reliability

9 min read

4

Flow and Congestion Control

9 min read

5

TCP in the Real World

9 min read

5

The Application Layer

5 chapters

1

DNS

8 min read

2

HTTP Fundamentals

9 min read

3

HTTP/2, HTTP/3 and Performance

7 min read

4

REST, WebSockets and Real-Time

8 min read

5

Email and Other Protocols

9 min read

6

Network Security

4 chapters

1

The Threat Model

7 min read

2

Cryptography for Networks

9 min read

3

TLS and HTTPS

9 min read

4

Firewalls, VPNs and Defence in Depth

9 min read

7

Modern and Distributed Networking

4 chapters

1

Load Balancing and Reverse Proxies

9 min read

2

CDNs and Edge Caching

8 min read

3

Cloud Networking

8 min read

4

Service-to-Service Communication

10 min read

8

Practice and Capstone

4 chapters

1

The Diagnostic Toolkit

9 min read

2

Debugging Methodically

9 min read

3

Capstone: HTTP From Sockets

11 min read

4

Where to Go Next

7 min read