User Manual

Overview
Networking Ethernet/IP networks
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Port-based VLANs
Port-based VLANs distribute a virtual managed switch to multiple switches. Each VLAN is identified by a
VLAN-ID between 1 and 4094 with VLAN-ID 1 reserved as the default VLAN.
The switch's IP address is exclusively reachable via ports that are fixed on this VLAN. In the example
above, ports 1 to 4 are assigned to VLAN 1001; ports 5 to 8 to VLAN 1002, in other words, communication
can only take place between devices 1 to 4 on the same VLAN. This is referred to as port-based VLANs or
often as untagged VLANs, since the Ethernet frames from the switch to the end device no longer have a
tag.
Benefits:
● Port-based VLANs reduce the need, especially on smaller installations, for a physical switch on each
network.
● The end devices do not need to support VLAN tagging per IEEE 802.1q, since the switch takes over this
task.
Tagged VLANs
In contrast to untagged VLANs, tagged VLANs are frame-based rather than port-based. A port is assigned
to multiple VLANs rather just a single one. Each frame receives a VLAN tag so that the switch knows to
which VLAN an Ethernet frame belongs.
Benefits:
● A single cable suffices to connect both switches.
Disadvantages:
● Each switch (not end devices) must support tagging per IEEE 802.1q as the end device does not
recognize the data packet and rejects it, i.e. no communication occurs.
Networking in a star topology
Benefits:
● Less expensive installation
● Low operating costs
● Improved overview
AS01
AS02
AS03
AS04
Switch A
1
2
3
4
5
6
7
8
AS01 AS02 AS03 AS04
Switch A
1
2
3
4
5
6
7
8
AS05 AS06
AS07
AS08
Switch B
1
2
3
4
5
6
7
8