Wired Switching - Motorola WiNG 4.4 Reference Manual

1 - 16 WiNG 4.4 Switch System Reference Guide

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
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).
Multiple IP addresses for a single VLAN allow the configuration of multiple IP addresses, each belonging to different
subnet. Class configuration allows a DHCP client to obtain an address from the first pool to which the class is assigned.
For more information, see
1.2.3.3 DDNS
Dynamic DNS (DDNS) keeps a domain name linked to a changing IP address. Typically, when a user connects to a network,
the user's ISP assigns it an unused IP address from a pool of IP addresses. This address is only valid for a short period.
Dynamically assigning IP addresses increases the pool of assignable IP addresses. DNS maintains a database to map a
given name to an IP address used for communication on the Internet. The dynamic assignment of IP addresses makes it
necessary to update the DNS database to reflect the current IP address for a given name. Dynamic DNS updates the DNS
database to reflect the correct mapping of a given name to an IP address.
1.2.3.4 VLAN Enhancements
The switch has incorporated the following VLAN enhancements:
• Network interfaces operate in either trunk or access modes.
• A network interface in access mode can only send and receive untagged packets.
• A trunk port can now receive both tagged and untagged packets. Each ethernet port is assigned a native VLAN.
5-4.
Configuring the DHCP User Class on page 5-18.