2: Product Overview
XPress-Pro SW 94000 User Guide 14
Enhanced Security
Because VLANs are self-contained, only the devices within the same VLAN can
communicate with each other. If a device in one VLAN wants to communicate with a
device in another VLAN, the traffic must go through a router.
VLAN Membership
VLAN implementation allows:
VLANs across multiple switches by using explicit or implicit tagging and the GARP/GVRP
protocol defined in IEEE802.1p and 802.1Q.
An end station’s network interface card may belong to multiple VLANs.
A switch port may be associated with multiple VLANs.
Definitions of VLAN Membership
VLAN implementation allows VLAN membership to be defined based on ports. Port-
based VLANs are organized by physical port number. For example, switch ports 1, 2, 4
and 6 can be grouped on VLAN, while server ports 3, 5, 7 and 8 can be on another
VLAN. Broadcasts from servers within each group would only go to the members of its
own VLAN. This ensures that broadcast storms cannot cause a network meltdown due to
traffic volume.
VLAN Membership Learning
Port-based VLAN is defined using a static binding between a VLAN and its associated
ports. The switch’s forwarding decision is based on the destination MAC address and its
associated port ID. Therefore, to make valid forwarding and flooding decisions, the switch
learns the relationship of the MAC address to its related port – and thus to the VLAN – at
runtime.
Remote VLAN Learning
In addition to providing network management tools that allow network administrators to
statically add and delete VLAN member ports, the switch also supports GVRP (GARP
VLAN Registration Protocol). GVRP allows for dynamic registration of VLAN port
members within switch and across multiple switches.
Other than supporting dynamic updating of registration entries in a switch, GVRP is used
to communicate VLAN registration information to other VLAN-aware switches, so that a
VLAN member can cover a wide span of switches on a network.
GVRP allows both VLAN-aware workstations and switches to issue and revoke VLAN
memberships. VLAN-aware switches register and propagate VLAN membership to all
ports that belong to the active topology of the VLAN.
VLAN CONFIGURATION
The Xpress-Pro SW 94000 switch provides a Local/Remote Management Console
Interface for VLAN configuration and management An SNMP-based VLAN MIB is also
provided.