Installation manual

IP DECT Installation Page 99
15-601085 Issue 04f (11 June 2009)IP Office
Appendix: DHCP Server Operation
7.2 802.1Q VLAN Support
The IP Base Stations support VLANs according to IEEE 802.1Q.
VLAN can be administered either:
· On a per port basis of the LAN switch assuming that the IP Base Stations are connected to a single port of a
switched Ethernet environment.
or
· By setting a VLAN ID on the IP Base Station corresponding to the VLAN they should be operating in. In this case
VLAN tagging has to be set to the IP DECT base station. The following sections refer to this case only.
The benefit of VLAN tagging by the IP DECT Base Station, is to set 802.1p priority within Ethernet frames. The scope of
the following description comprises VLAN tagging and obtaining the VLAN ID. Quality of Service mechanisms like 802.1p
priority and DiffServ are not covered in this section.
· IP DECT base stations are not be able to support VLAN ID 0 as described later in this section. Any other valid
VLAN ID can be configured.
· If 802.1Q tagging is enabled and a VLAN ID is configured, all traffic from an IP Base Station will be tagged with
this VLAN ID.
· Once a VLAN ID is set on the IP Base Station, incoming frames are only accepted if they are tagged as well.
Therefore the switch port has to be configured as a tagged trunk for this VLAN.
· VLAN configuration can be done using DHCP or via OM Configurator.
· The usage of VLAN does influence the boot up process of the IP Base Station because VLAN configuration takes
place during the boot phase.
802.1Q VLAN tagging is enabled if the VLAN ID is set, either through Public Option 225 is using DHCP or through the
ADMM Configurator tool if using static addressing. If no VLAN ID is set, 802.1Q is disabled.
VLAN ID 0 means that the IP Base Station’s traffic belongs on the port/native VLAN. The Ethernet switch port to which
the IP Base Station is connected must be configured to accept 802.1Q tagging for this to work, and the switch must
interpret VLAN ID 0 as the port/native VLAN ID, as per the IEEE 802.1Q standard.
The packets from the IP Base Station are tagged with VLAN ID 0 and the packets send to the IP Base Station are tagged
with the port/native VLAN ID. This scenario does not work, because the IP Base Station supports only one VLAN
ID in both directions. That means the VLAN ID in the receive direction must be the same as the send
direction.