PLANET WGSW-5242 - Manual (Page 56)

User’s Manual of WGSW-5242
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VLANs provide greater network efficiency by reducing broadcast traffic, and allow you to make network changes without having
to update IP addresses or IP subnets. VLANs inherently provide a high level of network security since traffic must pass through
a configured Layer 3 link to reach a different VLAN.
This Managed Switch supports the following VLAN features:
 Up to 255 VLANs based on the IEEE 802.1Q standard
 Distributed VLAN learning across multiple switches using explicit or implicit tagging and GVRP protocol
 Port overlapping, allowing a port to participate in multiple VLANs
 End stations can belong to multiple VLANs
 Passing traffic between VLAN-aware and VLAN-unaware devices
 Priority tagging
The Managed Switch allows 4k user-manageable VLANs.
■ IEEE 802.1Q Standard
IEEE 802.1Q (tagged) VLAN are implemented on the Switch. 802.1Q VLAN require tagging, which enables them to span the
entire network (assuming all switches on the network are IEEE 802.1Q-compliant).
VLAN allow a network to be segmented in order to reduce the size of broadcast domains. All packets entering a VLAN will only
be forwarded to the stations (over IEEE 802.1Q enabled switches) that are members of that VLAN, and this includes broadcast,
multicast and unicast packets from unknown sources.
VLAN can also provide a level of security to your network. IEEE 802.1Q VLAN will only deliver packets between stations that are
members of the VLAN. Any port can be configured as either tagging or untagging. The untagging feature of IEEE 802.1Q VLAN
allows VLAN to work with legacy switches that don't recognize VLAN tags in packet headers. The tagging feature allows VLAN
to span multiple 802.1Q-compliant switches through a single physical connection and allows Spanning Tree to be enabled on all
ports and work normally.
Any port can be configured as either tagging or untagging. The untagging feature of IEEE 802.1Q VLAN allow VLAN to work
with legacy switches that don’t recognize VLAN tags in packet headers. The tagging feature allows VLAN to span multiple
802.1Q-compliant switches through a single physical connection and allows Spanning Tree to be enabled on all ports and work
normally.
Some relevant terms:
- Tagging - The act of putting 802.1Q VLAN information into the header of a packet.
- Untagging - The act of stripping 802.1Q VLAN information out of the packet header.