Specifications

1 - 1
Chapter 1 BASICS OF ETHERNET NETWORK
Note
This textbook mainly describes how to use MELSEC-Q Series Ethernet module.
For details of general computer network technology (TCP/IP communication, etc.),
refer to commercially-available textbooks.
In addition, for details of the Ethernet module, refer to the relevant manuals.
1.1 Ethernet
The development of Ethernet was started by Xerox Palo Alto Research Center in the
U.S. in 1973, and Ethernet has been approved as a network technology by ISO and
ANSI/IEEE standards.
Lately it is widely used for networking gear and communication channel, etc. (*1)
For actual network operation, hardware technique such as transmission lines which is
defined by Ethernet (in the narrow sense) and communication technology for TCP/IP
communication (protocol: a procedure for data transmission) are necessary.
General Ethernet specifications are shown below.
Specification 10BASE5 10BASE2 10BASE-T 100BASE-TX
Data transmission speed 10 Mbps 10 Mbps 10 Mbps 100 Mbps
Maximum segment
length
500m 185m 100m 100m
Maximum network length
(or Maximum
node-to-node interval)
2500m
(5 segments)
925m
(5 segments)
Minimum node-to-node
distance
2.5m 0.5m
Cable
Coaxial 50
(12mm
diameter)
*Known as: yellow cable
Coaxial 50
(5mm
diameter)
UTP(unshielded twisted
pair cable) category 3
UTP(unshielded twisted
pair cable) category 5,
STP(unshielded twisted
pair cable) IBM Type1, 2
Network topology Bus Bus Star Star
*1 Communication lines (10 BASE-T, 10BASE-TX, 10 BASE5 and 10BASE2) are
referred to as "Ethernet" in this textbook.
[Connection using 10BASE2/10BASE5] [Connection using 10BASE-T/100BASE-TX]
Segment length
Node
Segment length
Segment length
Repeater
Repeater
Maximum
node-to-node
distance
Node
Node
Node
Node
Transceiver
Terminator
* There is no transceiver when connecting using 10BASE2.
E
7
1
Hub
Maximum
100m (5m)
Maximum
100m
Up to 4 (2) stages
are allowed
for cascade
connection
* The value in parentheses ( ) is used for connection using
100BASE-TX.