General Network Information; Network Protocol - Toshiba E-STUDIO190F Service Manual

9 General Network Information

9.1.

Network Protocol

9.1.1. OSI Reference Mode
Having a model in mind helps you understand how the pieces of the network puzzle fit together. The most
commonly used model is the Open System Interconnection (OSI) reference model. The OSI model, first
released in 1984 by the International Standards Organization (ISO), provides a useful structure for defining
and describing the various processes underlying networking communications.
The OSI model organizes communication protocols into seven layers. Layer 1, the Physical (Hardware)
layer, consists of protocols that deal with how data is transferred across the transmission media. At the
opposite end, Layer 7, the Application layer, interfaces the network services with the applications (software)
in use on the computer. The five layers in between, Data Link, Network, Transport, Session and
Presentation - perform intermediate communication tasks. In essence the OSI model is a framework that
describes how a function from one computer is transmitted to another computer on the network.
Layer
7 Application
6 Presentation
5 Session
4 Transport
3 Network
2 Datalink
1 Physical
Name
TCP, UDP
PPP...
OSI Reference Model and Network Terms
Function
NetBIOS, Windows, Sockets, etc...
IP, IPX, etc...
ODI Driver, NDIS Driver
Router
NIC
SW Hub
Repeater
Hub
253
Protocol
TDI
TCP/IP
IPX/SPX
Net BEUI
Apple Talk
IP Address etc...
Ethernet
MAC Address
Token Ring
RS-232C, X21...
SMB
SMTP
FTP
DNS
HTTP
Telnet
etc...
etc...
FDDI
ATM
etc...