Layer provides end-to-end delivery across multiple networks with logical addressing (IP) and routing.
Core concepts:
- IP addressing: -bit (IPv4) or -bit (IPv6)
- Routing: finding paths through networks
- Fragmentation: breaking packets for smaller links
Routers operate here. They examine destination IPs and forward packets toward their target. Each router makes independent decisions.
Layer is connectionless. IP does "best effort" routing without guarantees. Reliability comes from Layer .