Network+ OSI Model

Physical

Layer 1

Data Link

Layer 2

Network

Layer 3

Transport

Layer 4

Session

Layer 5

Presentation

Layer 6

Application

Layer 7

Application

Proxy Server

Application

DNS (Domain Name Service)

Application

FTP (File Transfer Protocol)

Application

HTTP (Hyper Text Transfer Protocol)

Application

NFS (Network File System)

Application

NNTP (Network News Transfer Protocol)

Application

POP3 (Post Office Protocol v3)

Application

SMTP (Simple Mail Transfer Protocol)

Application

SNMP (Simple Network Management Protocol)

Application

Telnet

Application

TFTP (Trivial File Transfer Protocol)

Application

Take data from applications

Application

Ensure all necessary resources are available

Application

Initialize services and the network for data transmission

Presentation

ASCII

Presentation

GIF

Presentation

JPEG

Presentation

TIFF

Presentation

Reformat or translate between different characters sets

Presentation

Encrypting/decrypting and compression/ecompression

Presentation

Provides support for error recovery

Session

NetBIOS

Session

RPC - Remote Procedure Calls

Session

X-Windows

Session

Assumes a reliable virtual connection

Session

Establishing, maintaining, synchronization and terminating connections

Session

Port numbers assigned and maintained

Transport

ATP (Apple Talk Protocol)

Transport

NetBeui

Transport & Data Link

PPTP (Point to Point Tunneling Protocol)

Transport

SPX (Sequenced Packet Exchange)

Transport

TCP (Transmission Control Protocol)

Transport

UDP (User Datagram Protocol)

Transport

Packages data into segments

Transport

Provides flow control

Transport

Performs end-to-end transport of data

Network

ARP (Address Resolution Protocol)

Network

ICMP (Internet Control Message Protocol)

Network

IP (Internet Protocol)

Network

IPX (Internet Packet Exchange)

Network

NetBios/NetBeui

Network

Break segmented data into packets and sequences them

Network

Assign logical addresses to packets

Network

Routes packets

Data Link

Switches

Data Link

Bridges

Network

Router

Network

Brouter

Data Link

WAP (Wireless Access Points)

Data Link & Physical

NIC

Data Link

802.1Q - 802.3 (Ethernet) - 802.11 a/b/g (Wireless)

Data Link

Token Ring

Data Link

Break data packet into frames

Data Link

Manages Hardware Addresses (MAC)

Data Link

Defines the topology of the network based on IEEE 802.x standards

Data Link

Provide error and flow control

Physical

Repeater

Physical

Hub

Physical

Cables

Physical

Physically, mechanaically and/or electronically connect network devices

Physical

Break frames into raw binary bits

Physical

Defines the network media used