In the AMC, navigate to System Configuration > Services.
In the Access Services section, under Network tunnel service area, Configure. The Network Tunnel Service page displays.
In the IP Address Pools section, click the + (New) icon. The IP Address Pool page displays.
In the Name field, type a name for the address pool.
In the Description field, type a descriptive comment about the address pool.
Click User-mapped address pool to configure a pool in which IP address allocation is made during the authorization process, as part of authentication. You would choose this setting if, for example, you have an application that requires a one-to-one relationship between an assigned IP address and a user.
(Optional) To change the virtual interface settings for configuring the client interface, click to expand the Advanced area. The Virtual interface settings are preconfigured with the DNS server, WINS server, and Search domains as defined on the Network Settings page. (For more information, see Configuring Basic Network Settings.) To change these settings, select the Customize default settings checkbox and then
specify custom values for any settings that you want to change.