Protocol-Sensitive Vlans; Corebuilder 2500 Protocol-Sensitive Vlan Configuration; Protocol Suite - 3Com CoreBuilder 2500 User Manual

About VLANs 2-3

Protocol-Sensitive VLANs

The CoreBuilder 2500 system forwards, to all ports, any data that has a
broadcast, multicast, or unknown destination address. This process is
referred to as bridge flooding.
With protocol-sensitive VLANs, you can restrict flood traffic for routable
and nonroutable protocols. Protocol-sensitive VLANs have a relatively
simple configuration, grouping one or more switch ports together for a
specified network Layer 3 protocol, such as IP or AppleTalk. These VLANs
determine flooding based on the network layer protocol of the frame. In
addition, for IP VLANs, you can make flooding decisions based on Layer 3
subnetwork address information.
In a multiprotocol environment, protocol-sensitive VLANs can effectively
control broadcast and multicast flooding. They operate independently of
each other. In addition, the same switch port can belong to multiple
VLANs. For example, you can assign port 1 on a CoreBuilder 2500 system
to several IP subnetwork VLANs: one IPX VLAN, one AppleTalk VLAN, and
one NetBIOS VLAN.
Although two or more types of VLANs can coexist within the
CoreBuilder 2500 system, when a switch evaluates received data in a
multiple VLAN configuration, port group VLANs, MAC address group
VLANs, and application-oriented VLANs always take precedence over
protocol-sensitive VLANs.
CoreBuilder 2500 The CoreBuilder 2500 protocol-sensitive VLAN configuration includes
Protocol-Sensitive three elements: the protocol suite, the switch ports, and the Layer 3
VLAN Configuration addressing information for IP VLANs.

Protocol Suite

The protocol suite describes which protocol entities can comprise a
protocol-sensitive VLAN. For example, CoreBuilder 2500 VLANs support
the IP protocol suite, which is made up of the IP, ARP, and RARP protocols.