Alcatel Carrier Internetworking Solutions Omni Switch/Router - Manual (Page 557)

Non-Mobile Groups and AutoTracker VLANs
Page 19-15
Non-Mobile Groups and AutoTracker VLANs
Non-mobile Groups are comprised of physical entities—switch ports. Groups can span multi-
ple switches, but they are still made up of physical ports that you can see and touch. But just
as physically-based broadcast domains are limited, entirely port-based Groups can also be
limiting. In a large, flat, switched network, broadcast traffic can overload the network. There
needs to be a method for subdividing traffic even further. That’s where virtual networks, or
VLANs, come into play.
VLAN s are created within a Group to subdivide network traffic based on specific criteria. The
criteria you use to define a VLAN are called AutoTracker ™ policies. AutoTracker policies can
be defined by port, MAC address, protocol, network address, a user-defined policy, or a multi-
cast policy. VLAN s are described in more detail in Chapter 22, “Managing AutoTracker VLANs”
and Chapter 23, “Multicast VLAN s.”
Routing in a Non-Mobile Group
Communication within a Group containing only the default VLAN is switched; the ports are in
the same broadcast domain and do not require routing to communicate. Communication
between
VLAN s in the same Group or to VLAN s in other Groups requires routing. That’s why
all VLAN s—including the default VLAN within each Group—may contain their own virtual
router port. A virtual router port for each VLAN can be configured to support IP and/or IPX
routing. If you do not configure a virtual router port for a VLAN , the devices in that VLAN will
not be able to communicate with devices in other VLAN s unless there is an external router
between the VLAN s.
Each OmniS/R supports up to 32 virtual router ports. A single router port, using one MAC
address, can support IP routing, IPX routing, or both types of routing. When you enable a
router port for a default VLAN , you are actually creating a static route to that VLAN . Routing is
covered in more detail in Chapters 25 and 27.
♦ Note ♦
For mobile, non-mobile groups and AutoTracker
VLANs, the router port operational status is not active
unless an active switch port is a member of the group
or VLAN.