User`s manual

Configuring VLANs - Overview
VLANs help you manage traffic and improve network performance. When you configure VLANs, the Switch
forwards and filters packets more efficiently. It does so by reading VLAN information contained in the packet
header and updating VLAN membership tables by what it learns. It can also insert VLAN information into the
packet and transfer it to other switches on the network.
Static and dynamic VLANs
The Switch can have up to 4,096 static or dynamic VLANs based on:
port
●
MAC address●
network protocol●
Port-based VLANs
Port-based VLANs logically group together one or more ports on the Switch. Packets that the Switch receives
and identifies as belonging to a port-based VLAN are forwarded only over the ports assigned to that VLAN.
The Switch supports three types of port-based VLANs:
a single default port-based VLAN
●
static port-based VLANs that you create●
dynamic port-based VLANs created using GVRP●
The default VLAN
The Switch is shipped with a default port-based VLAN with a VID of 1. All ports on the Switch are included in this
VLAN. When you configure static port-based VLANs, the ports in the newly-created VLAN are removed from the
default VLAN. If a port is deleted from a static port-based VLAN, the Switch automatically places it back into the
default VLAN.
Static port-based VLANs
Static port-based VLANs are created to physically segment traffic or to set up routing interfaces. The switch port
you specify in a port-based VLAN is the physical port on the Switch. You create a routing interface by first
creating a port-based VLAN, then assigning an IP address to it.
Dynamic 802.1Q port-based VLANs using GVRP
The Switch can automatically and dynamically create a port-based VLAN or add and delete ports from any VLAN
that exists on the Switch. The Switch does this through the GARP VLAN Registration Protocol (GVRP).
MAC address-based VLANs
MAC address-based VLANs are always statically configured and maintained. They are suited to networks where
a workstation moves with its user, such as college and university campuses and corporations with rapidly
changing physical environments or mobile users. The Switch automatically locates the end station wherever it is
on the network.
Network protocol-based VLANs
Protocol-based VLANs are an effective way to segment your network into broadcast domains according to the
network protocols in use. Traffic generated by any network protocol—IPX , Appletalk, NETBEUI, legacy systems
using mainframe protocols—can be automatically confined to its own VLAN.
The Switch does this by inspecting the ethertype field of all incoming packets to see which protocol is there. If
there is no existing VLAN for that protocol, the Switch creates a new VLAN with that source port as a member. If
a VLAN already exists for that protocol, it makes the source port a member of that VLAN.
A summary of the Switch's VLAN capabilities
When a manager the Switch will
creates any type of static VLAN or enables GVRP
confine VLAN traffic to LAN segments forming
paths from the source to all VLAN members
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