Phase 6: Networking
Linux is the networking OS. From tiny embedded routers to hyperscale cloud load balancers, Linux's networking stack powers it all. Understanding how packets travel through the kernel — and how to control that journey — is essential for anyone working with servers, containers, or cloud infrastructure.
What You'll Learn
1. Linux Networking Stack
How a packet travels from NIC to application — through every kernel layer.
Intermediate2. Network Namespaces
How containers get isolated networking — virtual NICs, routing tables, iptables.
Intermediate3. iptables & nftables
Packet filtering, NAT, and firewalling with iptables and its successor nftables.
Intermediate4. Netfilter Hooks
The kernel hook points where iptables, conntrack, and NAT intercept packets.
Advanced5. Routing Table
How Linux decides where to send packets — routes, metrics, and policy routing.
Intermediate6. Traffic Control (tc)
Rate limiting, shaping, and queuing disciplines with the tc command.
Advanced7. Unix vs TCP Sockets
When to use Unix domain sockets vs TCP — performance, security, and use cases.
Intermediate8. /proc/net
Reading network stats, connections, and routing tables directly from the kernel.
IntermediateFrequently Asked Questions
What will I learn here?
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