| Couche | Nom | Fonction principale | Exemples |
|---|---|---|---|
| 7 | Application | Interfaces utilisateur / applis reseau | HTTP, DNS, FTP, SMTP |
| 6 | Presentation | Encodage, chiffrement, compression | JPEG, SSL/TLS, MPEG |
| 5 | Session | Maintien des connexions | NetBIOS, RPC, SMB |
| 4 | Transport | Fiabilite, flux, ports | TCP, UDP |
| 3 | Reseau | Adressage IP, routage | IP, ICMP, IGMP |
| 2 | Liaison de donnees | Trames, adressage MAC | Ethernet, PPP, VLAN |
| 1 | Physique | Transmission brute, support materiel | RJ45, Fibre, Wi-Fi |