Extreme Networks ExtremeWare XOS 10.1, Manual

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Types of VLANs
ExtremeWare XOS 10.1 Concepts Guide 67
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The server connected to port 25 on system 1 is a member of both VLAN Marketing and VLAN Sales.
• All other stations use untagged traffic.
As data passes out of the switch, the switch determines if the destination port requires the frames to be
tagged or untagged. All traffic coming from and going to the server is tagged. Traffic coming from and
going to the trunk ports is tagged. The traffic that comes from and goes to the other stations on this
network is not tagged.
Mixing Port-Based and Tagged VLANs
You can configure the switch using a combination of port-based and tagged VLANs. A given port can
be a member of multiple VLANs, with the stipulation that only one of its VLANs uses untagged traffic.
In other words, a port can simultaneously be a member of one port-based VLAN and multiple
tag-based VLANs.
NOTE
For the purposes of VLAN classification, packets arriving on a port with an 802.1Q tag containing a
VLANid of zero are treated as untagged.
Protocol-Based VLANs
Protocol-based VLANs enable you to define a packet filter that the switch uses as the matching criteria
to determine if a particular packet belongs to a particular VLAN.
Protocol-based VLANs are most often used in situations where network segments contain hosts running
multiple protocols. For example, in Figure 6, the hosts are running both the IP and NetBIOS protocols.
The IP traffic has been divided into two IP subnets, 192.207.35.0 and 192.207.36.0. The subnets are
internally routed by the switch. The subnets are assigned different VLAN names, Finance and Personnel,
respectively. The remainder of the traffic belongs to the VLAN named MyCompany. All ports are
members of the VLAN MyCompany.