Key Concepts; Multiple Ip Interfaces Per Vlan; Media Access Control (Mac) Address - 3Com corebuilder 3500 Implementation Manual

Key Concepts

Multiple IP Interfaces
per VLAN
Media Access Control
(MAC) Address
IP routers use the following elements to transmit packets:

Multiple IP Interfaces per VLAN

Media Access Control (MAC) addresses
Network addresses
IP addresses
Router interfaces
Routing tables
Address Resolution Protocol (ARP)
Internet Control Message Protocol (ICMP)
You can overlap IP interfaces without configuring a separate VLAN for
each subnet. Multiple IP interfaces can share the same VLAN, allowing
multiple subnets to be routed on the same 802.1Q VLAN.
You can define up to 32 IP interfaces on the system. This includes IP
routing interfaces for static VLANs, IP VLANs created by router ports or
any combination of static VLANs and router port IP VLANs.
If you define multiple interfaces for an IP VLAN, you cannot subsequently
modify that IP VLAN to supply Layer 3 address information. If only one
routing interface is defined for the IP VLAN, then you can supply Layer 3
address information as long as it matches the Layer 3 information that is
specified for the routing interface. This action converts the IP VLAN into a
network-based VLAN.
If you use network-based VLANs, you are limited to defining only one IP
routing interface for that VLAN. When you define an IP routing interface
for a static VLAN already configured, the system will not allow you to
select a network-based IP VLAN that already has a routing interface
defined for it.
If you add or change more than one IP interface associated with the same
VLAN, disable the ICMP Redirect option for optimal performance.
The MAC address refers to a physical hardware address. On a LAN, the
MAC address is the unique hardware number of your device. The MAC
address on an Ethernet LAN is the same as your Ethernet address.
Key Concepts 263