Private Vlan - Siemens SCALANCE XM-400 Configuration Manual

Technical basics
4.4 VLAN
The device has multiple parallel queues in which the frames with different priorities can be
processed. As default, first, the frames with the highest priority are processed. This method
ensures that the frames with the highest priority are sent even if there is heavy data traffic.
Canonical Format Identifier (CFI)
The CFI is required for compatibility between Ethernet and the token Ring.
The values have the following meaning:
Value
0
1
VLAN ID
In the 12-bit data field, up to 4096 VLAN IDs can be formed. The following conventions apply:
VLAN ID
0
1- 4094
4095
4.4.3

Private VLAN

With a private VLAN (PVLAN) you can divide up the layer 2 broadcast domains of a VLAN.
A private VLAN consists of the following units:
● A primary private VLAN (primary PVLAN)
The VLAN that is divided up is called primary private VLAN.
● secondary private VLANs (secondary PVLAN)
Secondary PVLANs exist only within a primary PVLAN. Every secondary PVLAN has a
specific VLAN ID and is connected to the primary PVLAN.
Secondary PVLANs are divided into the following types:
– Isolated Secondary PVLAN
– Community Secondary PVLAN
40
Meaning
The format of the MAC address is canonical. In the canonical representation of the MAC
address, the least significant bit is transferred first. Standard-setting for Ethernet switches.
The format of the MAC address is not canonical.
Meaning
The frame contains only priority information (priority tagged frames) and no valid
VLAN identifier.
Valid VLAN identifier, the frame is assigned to a VLAN and can also include priority
information.
Reserved
Devices within an isolated secondary PVLAN cannot communicate with each other via
layer 2.
Devices within a community secondary PVLAN can communicate with each other
directly via layer 2. The devices cannot communicate with devices in other communities
of the PVLAN via layer 2.
SCALANCE XM-400/XR-500 Web Based Management (WBM)
Configuration Manual, 05/2017, C79000-G8976-C248-12