SI-Ethernet User Guide
17
Issue: 3
Sa
fe
In
Me
ch
E
G
Pa
ra
Key
an
PC T
Sec
Di
G
Ind
ex
5
Getting started
5.1
Network design considerations
Ethernet is an open system allowing many different vendors to design and supply equipment.
When designing an industrial network you must carefully consider the topology and data traffic on
the network to avoid potential problems.
To avoid bandwidth issues it is recommended that the control network is logically separate from any
other network. Where possible a physically separate network should be used. If this is not possible,
the use of managed network devices should be considered to prevent unnecessary traffic such as
broadcasts reaching the control network.
5.2
Addressing
The addressing system used on Ethernet uses two essential numbers for making connection, these
are the IP address and the subnet mask. The address allows a specific device to be located and
the subnet mask defines how many bits represent the subnet part of the address and how many
bits represent the node address (
see section 5.6.1 The IP address
on page 19). Generally devices
on different subnets can only communicate by using a gateway (
typically a router or firewall
).
5.3
Where do IP addresses come from?
Every address on a network must be unique. If you do not connect your network to any other
networks the assignment of IP addresses is not critical (
although using a standard system is
recommended
), as you have full control of the addresses used. The issue of addressing becomes
important when connecting multiple networks together or connecting to the Internet where there is
a strong possibility of duplication of addresses if a scheme is not followed.
5.4
Addressing etiquette
The following list details some points that should be considered when selecting addresses:
•
Reserve address space:
Ensure you have enough reserve address space on your chosen
addressing scheme to allow for future expansion.
•
Uniqueness:
Ensure your addresses are unique, every device on a subnet must have a
unique address.
•
Avoid reserved addresses:
For example the address 127.0.0.1 is reserved as the loop back
address.
•
Broadcast and system addresses:
The highest and lowest host address on a subnet are
reserved addresses.
•
Use a system:
Have a scheme for assigning your addresses, for example typically servers
may have a low IP address and routers a high IP address. It is not necessary to allocate
consecutive IP addresses so it is possible to reserve ranges for specific uses such as servers,
work stations or routers.
The use of un-switched hubs is not supported.
NOTE
Содержание Unidrive M600
Страница 1: ...User Guide SI Ethernet and Unidrive M Onboard Ethernet Part Number 0478 0137 03 Issue 3 ...
Страница 16: ...16 SI Ethernet User Guide Issue 3 Figure 4 3 Typical network topologies ...
Страница 215: ......
Страница 216: ...0478 0137 03 ...