Panasonic UF-E1, Service Manual

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UF-E1
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6.5. General Network Information
6.5.1. Network Protocol
6.5.1.1. 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 accross 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.
7 Application
Layer Name Function Protocol
6 Presentation
5 Session
4 Transport
3 Network
2 Datalink
1 Physical
NetBIOS, Windows, Sockets, etc...
SMB
SMTP
FTP
DNS
HTTP
Telnet
etc...
TCP/IP
IPX/SPX
Net BEUI
Apple Talk
etc...
Ethernet
Token Ring
FDDI
ATM
etc...
TDI
TCP, UDP
IP, IPX, etc...
PPP...
IP Address etc...
MAC Address
RS-232C, X21...
ODI Driver, NDIS Driver
Repeater
Hub
NIC
SW Hub
Router
OSI Reference Model and Network Terms