ISO network protocol hierarchy and common Protocol Division

Layer-7 network division

In 1978, the International Organization for Standardization (ISO) proposed the "Open System Interconnection Reference Model", the famous OSI/RM model (Open System Interconnection/Reference Model ). It divides the communication protocol of the computer network architecture into seven layers:
Layer 7: Application Layer
Layer 6: Presentation Layer
Layer 5: Session Layer
Layer 4: Transport Layer
Layer 3: Network Layer
Layer 2: Data Link Layer
Level 1: Physical Layer

Common protocols

Application Layer Protocol (Layer 7): FTP, telnet, SMTP, HTTP, Rip, NFS, DNS
Transport Layer Protocol (Layer 4): TCP and UDP
Network Layer Protocol (Layer 3): IP protocol, ICMP protocol, ARP protocol, RARP Protocol
Reference: http://baike.baidu.com/view/16603.htm