Installation guide

1-16 Motorola RF Switch Systen Reference
switches. This ensures a VLAN MU association is maintained even while the MU roams amongst cluster
members.
Roaming across a Layer 3 Mobility Domain
When an MU roams amongst switches in different Layer 3 mobility domains, Layer 3 ensures traffic is
tunneled back to the correct VLAN (on the home switch).
Interaction with Radius Assigned VLANs
Multiple VLANs per WLAN can co-exist with VLANs assigned by a Radius server. Upon association, an MU
is assigned to a VLAN from a pool of available VLANs. When the Radius server assigns the user another
VLAN, MU traffic is forwarded to that VLAN.
When 802.1x is used, traffic from the MU is dropped until authentication is completed. None of the MU data
is switched onto the temporarily VLAN. A Radius assigned VLAN overrides the statically assigned VLAN.
If the Radius assigned VLAN is among the VLANs assigned to a WLAN, it is available for VLAN assignment
in the future. If the Radius assigned VLAN is not one of the VLANs assigned to a WLAN, it is not available
for future VLAN assignment. To configure Multiple VLANs for a single WLAN, see Assigning Multiple VLANs
per WLAN on page 4-31.
1.2.3 Wired Switching
The switch includes the following wired switching features:
• DHCP Servers
• DHCP User Class Options
• DDNS
• VLAN Enhancements
• Interface Management
1.2.3.1 DHCP Servers
Dynamic Host Configuration Protocol (DHCP) allows hosts on an IP network to request and be assigned IP
addresses as well as discover information about the network to which they are attached. Each subnet may
be configured with its own address pool. Whenever a DHCP client requests an IP address, the DHCP server
assigns an IP address from that subnet’s address pool.
When a DHCP server allocates an address for a DHCP client, the client is assigned a lease, which expires
after an pre-determined interval. Before a lease expires, clients (to which leases are assigned) are expected
to renew them to continue to use the addresses. Once the lease expires, the client is no longer permitted to
use the leased IP address. For information on defining the switch DHCP configuration, see
DHCP Server Settings on page 5-3.
1.2.3.2 DHCP User Class Options
A DHCP Server groups clients based on defined user-class option values. Clients with a defined set of user-
class values are segregated by class. The DHCP Server can associate multiple classes to each pool. Each
class in a pool is assigned an exclusive range of IP addresses.
DHCP clients are compared against classes. If the client matches one of the classes assigned to the pool, it
receives an IP address from the range assigned to the class. If the client doesn't match any of the classes in
the pool, it receives an IP address from a default pool range (if defined).