You should be able to do that. However it have dependency on the authetication Protocols negotiated between Client and IC. The decision of what realms are available to the user within a sign-in policy is based on two factors. First, the order of realms in the list is considered. Realms at the top of the list are attempted. Second, the authentication protocol set that you choose must be compatible with the client or supplicant. To determine a compatible realm, the system looks for a RADIUS subprotocol that is compatible with the client or supplicantÍs available protocols, and the system automatically selects compatible realms. If the endpoint is using a UAC agent, the system presents a list of realms. Any realm with both outer and inner protocols that match the outer and inner protocols on the client is considered compatible. We have a detailed docuemntaion around this topic and you can access it from http://www.juniper.net/techpubs/en_US/uac5.0/topics/concept/uac-sign-in-auth-protocols-about.html
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