ZyXEL Communications XS3800-28, User Manual, Page: 426 / 789

Chapter 57 VLAN
XS3800-28 User’s Guide
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subnet it came from. The untagged packets from the same IP subnet are then placed in the same
subnet based VLAN. One advantage of using subnet based VLANs is that priority can be assigned to
traffic from the same IP subnet.
Note: Subnet based VLAN applies to un-tagged packets and is applicable only when you use
IEEE 802.1Q tagged VLAN.
For example, an ISP (Internet Services Provider) may divide different types of services it provides to
customers into different IP subnets. Traffic for voice services is designated for IP subnet 172.16.1.0/24,
video for 192.168.1.0/24 and data for 10.1.1.0/24. The Switch can then be configured to group incoming
traffic based on the source IP subnet of incoming frames.
You configure a subnet based VLAN with priority 6 and VID of 100 for traffic received from IP subnet
172.16.1.0/24 (voice services). You also have a subnet based VLAN with priority 5 and VID of 200 for
traffic received from IP subnet 192.168.1.0/24 (video services). Lastly, you configure VLAN with priority 3
and VID of 300 for traffic received from IP subnet 10.1.1.0/24 (data services). All untagged incoming
frames will be classified based on their source IP subnet and prioritized accordingly. That is video
services receive the highest priority and data the lowest.
Figure 321 Subnet Based VLAN Application Example
57.9 Configuring Subnet Based VLAN
Click the SWITCHING > VLAN > Subnet Based VLAN Setup link in the navigation panel to display the
configuration screen as shown.