Understanding and Types of OSI Layer

Understanding and Types of OSI Layer

The OSI OSI model layer consists of 7 layers. Where the top of the layer (layers 7, 6, and 5) is focused on the service form of an application. As for the bottom layer (layers 4, 3, 2 and 1) oriented about the flow of data from one end to the other.

OSI Reference Model Table

Name Layer	Function	Example
Application (layer 7)	Applications that communicate with each other between computers. Application layer on the communication services on an application.	Telnet, HTTP, FTP, WWW Browser, NFS, SMTP, SNMP
Presentation (Layer 6)	On the layer aims to define data formats, such as ASCII text, binary, and JPEG. JPEG	JPEG, ASCII, TIFF, GIF, MPEG, MIDI
Session (Layer 5)	Session layer how to start, control and apply a conversation (called session)	RPC, SQL, NFS, SCP
Transport (Layer 4)	In this layer, 4 can be selected whether to use the protocol that supports error recovery or not. Multiplexing of incoming data, sorting incoming data is not coming in sequence.	TCP, UDP, SPX
Network (Layer 3)	This layer sends data from end to end. To make delivery on this layer also do addressing. Defines the delivery path (routing).	IP, IPX, Appletalk DDP
Data Link (layer 2)	It sends data from various interfaces. Like sending data from 802.3 ethernets to High-Level Data Link Control (HDLC), it sends WAN data	IEEE 802.2/802.3, HDLC, Frame relay, PPP, FDDI, ATM
Physical (Layer 1)	This layer governs the different interface forms of a transmission medium. Different specifications eg connector, pin, pin usage, passing the electric current, encoding, dl light source.	EIA/TIA-232, V35, EIA/TIA- 449, V.24, RJ45, Ethernet, NRZI, NRZ, B8ZS

See also: Layer Concepts And Usefulness