Panasonic UF-E1 Service Manual page 158

UF-E1
6.5.1.2. Protocol
One reason for the popularity of TCP/IP is that no one vendor owns it, unlike the IPX/SPX, DNA, SNA or
Apple Talk protocol suites, all of which are controlled by specific companies. TCP/IP evolved in response to
input from a wide variety of inductry sources. Consequently, it is the most open of the protocol suites and is
supported by the widest variety of vendors. One huge advantage of using TCP/IP is that, it is required for
communication over the Internet, thus the Internet can be used as a communication backbone.
TCP/IP was originally designed by ARPANET (Advanced Research Project Agency) in 1969 for the UNIX
operating system. In early 1980, UNIX 4.2 BSD version was released. For more detailed information, an
RFC (Request for Comment) document is available from the IETF (Internet Engineering Task Force) on the
Internet at http://www.ietf.org/.
The Internet protocols do no map cleanly to the OSI reference model. The model for the Internet protocol
suite has four layers. From the illustration below, you can see the approximate relationship of the layers.
Layer
7 Application
6 Presentation
5 Session
4 Transport
3 Network
2 Data Link
1 Physical
6.5.1.3. Cable
For the network transmission media at the Physical layer on the OSI reference model, there are several
cable categories available. Category 5, 8 wire Unshielded Twisted Pair (UTP) cable is commonly used.
Shielded Twisted Pair cables are also available. The Impedance for the STP / UTP Ethernet cable is 100 Ω.
Category 3 is also used for the 10Base-T Ethernet.
OSI Reference Model
Comparison of the TCP/IP layers to the OSI model
Category
1
2
3
4
5
TCP/IP Base
Application This layer embraces functions of the OSI
Session, Presentation and Application layers.
Protocols at this layer provide network services.
Transport Compares to OSI Transport layer. Enables peer
communication between hosts on the internetwork.
Internet Corresponds roughly to the OSI Network layer.
Protocols move data between devices on networks.
Network Interface Corresponds to the bottom two layers of the OSI
model. This correspondence enables the TCP/IP
protocols to coexist with existing Data Link and
Physical layer standards.
This layer is concerned with all aspects of
transmitting and receiving data on the network.
Purpose
Voice grade telephone line
ISDN
10Base-T Token Ring (4M)
Token Ring (16M)
100Base-TX, ATM (155M)
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Function