TCP/IP Reference Model and OSI reference Model

TCP/IP Reference Model OSI Reference Model

Application Layer	Application Layer
	Presentation Layer
	Session Layer
Transport Layer	Transport Layer
Internetwork Interconnect Layer	Network layer
Network interface Layer	Data Link Layer
	Physical Layer

TCP/IP Reference Model :

The network interface layer is the interface between TCP/IP and various LANs or WANs.

The Internetwork interconnect layer has 4 main protocols: Internet Protocol (IP), Address Resolution Protocol (ARP), Reverse Address Resolution Protocol (RARP), and the Network Control Message Protocol (ICMP).

The transport layer has 2 major protocols, Transmission Control Protocol (TCP) and User Datagram Protocol (UDP). T CP Communication is based on connection-oriented, and typically requires three phases: TCP connection, packet transmission, and TCP connection removal.

The main protocols of the application layer are: DNS, SNMP, TFTP (Simple File Transfer Protocol), and so on, usually TCP protocol, HTTP, FTP, TELNET, SMTP and so on.

Same and different :

Both the OSI reference model and the TCP/IP Reference Model adopt the concept of hierarchy, but the former is a seven-layer model, and the latter is a four-layer structure. The main differences are as follows:

1. Services, interfaces and protocols
The concept of the OSI Reference Model clearly defines the three concepts and their relationships, while the TCP/IP reference model does not explicitly differentiate between services, interfaces, and protocols.
2. Relationship of models and protocols
OSI is a model first, then a protocol (universal, but difficult to achieve)
TCP/IP is a protocol first, followed by a model (practical, but less versatile)
3. Connection-oriented and non-connected services
The network layer of the OSI Reference Model provides both connection-oriented services and connectionless services. However, the transport layer only provides connection-oriented services.
The internetwork interconnect layer of the TCP/IP Reference model provides no connectivity services, while the transport layer provides connection-oriented services (TCP) and no-connection services (UDP).

TCP/IP Reference Model and OSI reference Model