User's Manual

Chapter 13: Client IP Configuration
TR0153 Rev. E1 99
13 Client IP Configuration via DHCP
Two configuration options exist for assigning IP addresses to client devices using DHCP:
• Each EnRoute500 hosts a local DHCP server and supplies IP addresses to devices
attaching to any of the client access interfaces
• A centralized DHCP server supplies IP addresses to client devices, with the EnRoute500s
relaying DHCP messages between client devices and the centralized server.
The DHCP modes for client access interfaces in a mesh neighborhood can be set individually
to use a local server, a centralized server, or be disabled. This allows a mesh to contain
devices with client access interfaces supporting a combination of centralized and localized
DHCP.
13.1 Using the Local DHCP Server
The EnRoute500 can be set to serve IP addresses to client devices on enabled VAP interfaces
and the Ethernet interface on repeater devices using DHCP.
The IP addresses provided by the local DHCP server will be in the subnet defined by the LAN
prefix, mesh ID, node ID, and the IP address range start address and size parameters in the
appropriate client access interface. For example, for the ‘wlan1’ interface, the start and end of
the address range are:
Start address = <LAN prefix>.
<Mesh ID>.
<Node ID>.
<wlan1 IP address range start address> + 1
End address = <LAN prefix>.
<Mesh ID>.
<Node ID>.
< wlan1 IP address range start address > -
< wlan1 IP address range size > - 2
The EnRoute500 can be configured to set aside a number of IP addresses for client devices
that will use a static IP address. These IP addresses are taken from the pool that DHCP
assigns IP addresses from. Thus, increasing the number of IP addresses set aside for devices
with static IP addresses will reduce the size of the DHCP address pool. The DHCP reserve
parameter controls the number of IP addresses that will be reserved for static use. By default,
this parameter is set to zero, assigning the maximum possible number of IP addresses to the
DHCP pool. You may reserve the entire range of IP addresses, but the EnRoute500 will use at
least the highest address in the range for DHCP.