Setting The Dhcp Server Configuration; Defining Dhcp Pools - Motorola WiNG 5.5 Reference Manual

9.3 Setting the DHCP Server Configuration

Services Configuration
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 where they reside. Each subnet can 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 the 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, wireless 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. The DHCP server ensures all
IP addresses are unique, and no IP address is assigned to a second client while the first client's assignment is valid (its lease
has not expired). Therefore, IP address management is conducted by the DHCP server, not an administrator.
AP7131, AP6522, AP6522M, AP6532, AP6562, AP8132, AP8232, AP7181 and AP7161 model access points have an internal
DHCP server resource. However, AP6511 and AP6521 models do not have an onboard DHCP server resource and an external
resource must be used.
The DHCP server groups wireless clients based on defined user-class option values. Clients with a defined set of user class
values are segregated by class. A 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.
A single DHCP server configuration is supported by the access point, no separate DHCP policies can be defined and maintained.
For more information, refer to the following:
•

Defining DHCP Pools

• Defining DHCP Server Global Settings
• DHCP Class Policy Configuration
9.3.1 Defining DHCP Pools
Setting the DHCP Server Configuration
A pool (or range) of IP network addresses and DHCP options can be created for each IP interface configured. This range of
addresses can be made available to DHCP enabled wireless devices within the network on either a permanent or leased basis.
DHCP options are provided to each DHCP client with a DHCP response and provide DHCP clients information required to access
network resources such as a default gateway, domain name, DNS server and WINS server configuration. An option exists to
identify the vendor and functionality of a DHCP client. The information is a variable-length string specified by the DHCP client's
vendor.
To define the parameters of a DHCP pool:
1. Select Configuration
2. Select Services.
3. Select DHCP Server. The DHCP Pool tab displays by default.
tab from the web user interface.
Services Configuration 9 - 15