NETGEAR® ProSAFE® WC9500 High Capacity Wireless Controller Configuring Microsoft DHCP for the Wireless LAN APPLICATION NOTES
INTRODUCTION NETGEAR ProSAFE WC9500 High Capacity Wireless Controllers support a wide range of wireless standards. In addition, several vendor-specific DHCP options can either be implemented automatically or they can be specifically assigned to NETGEAR ProSAFE access points managed by the WC9500 via the DHCP server.
lease duration and any standard and vendor-specific DHCP options the access point might have requested. At this point, the DHCP IP configuration process is complete. Each DHCP server must include a DHCP scope for each IPv4 or IPv6 subnet that it serves. Each DHCP scope must include a pool of IP addresses that can be leased to DHCP clients, as well as standard and vendor-specific DHCP options that can be assigned to DHCP clients that lease IP addresses from the scope.
DHCP Option 001 (Subnet Mask) The subnet mask option specifies the DHCP client’s subnet mask. If both the subnet mask and the router option are specified in a DHCP reply, the subnet mask option MUST be supplied first. Option Description Format Example 001 Subnet Mask IP Address 255.255.255.0 DHCP Option 003 (Router) The router option specifies a list of IP addresses for routers (default gateway) on the DHCP client’s subnet. Routers should be listed in order of preference.
DHCP Option 050 (Requested IP Address) The requested IP address option allows DHCP clients to request a particular IP address (DHCP Discover). Option Description Format Example 050 Requested IP Address IP Address 192.168.1.10 DHCP Option 051 (IP Address Lease Time) The IP address lease time option is supplied to DHCP clients along with the DHCP Offer to indicate how long the DHCP server willing to lease the IP address.
DHCP 055 (Parameter Request List) This parameter request list option is used by the DHCP clients to request values for specified configuration parameters. Option 055 Description Parameter Request List Format Example Integer 1 – Subnet Mask 3 – Router 6 – Domain Name Server 12 – Hostname 15 – Domain Name 28 – Broadcast Address 43 – Vendor-Specific Information DHCP 060 (Vendor Class Identifier) The class identifier option is used by DHCP clients to identify the type and configuration of a DHCP client.
CONFIGURATION The following configuration example demonstrates how to provision a Microsoft Windows DHCP Server to support vendor class and sub options for NETGEAR access points and apply the vendor class and sub option values to a scope. Step 1 – Define Vendor Class Open the DHCP Snap-In. Right-click on the applicable DHCP server branch and click Define Vendor Classes.
Step 3 – Define Class Enter NETGEAR AP in the Display name field and NETGEAR_WNC_AP in the ASCII field. If desired, enter a description of your choice. Step 4 – Define NETGEAR Sub-Options Right-click on the applicable DHCP server branch and select Set Predefined Options.
Step 5 – Add Option Class In the Predefined Options and Values window, select NETGEAR AP from the Option Class pulldown list and click Add. Step 6 – Define the Sub Option To enable discovery by the NETGEAR ProSAFE WC9500 Wireless Controller, define the sub option as shown below.
Step 7 – Assign NETGEAR Sub Options and Values to a Scope Right-click on a scope supporting the ProSAFE access points and select Configure Options.
Please Note: Configured scope options and values will be displayed in the DHCP scope and will only be assigned to NETGEAR ProSAFE access points that are being served from the scope. SUMMARY Using the NETGEAR ProSAFE WC9500 High Capacity Wireless Controller, we were able to provision a Microsoft Windows DHCP Server to support vendor class and sub options for NETGEAR access points, and then apply the vendor class and sub option values to a scope.
