Introduction to Network Access Server

Network Access Server is a server (application) that is used to authenticate and authorize a user (application/user/dial-up call etc) to use a shared resource such as internet etc. There could be various examples of it, such a NAS authenticate a user to use internet as user provides user-name and password n dial-up call.

As DIAMETER protocol is frequently used for AAA Authentication, Authorization and Accounting therefore applications based on DIAMETER that fulfill NAS requirement shall be very useful in telecom world.

Here in this article the intention is to explain, Diameter Network Access Server Application that complaint RFC-4005

Your Comments /Suggestions and Questions are always welcome,  shall clarify with best of knowledge. So feel free to put Questions.

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  1. I have a query
    Suppose a client sends a AAR packet with invalid userbane/password which is not present in server data base then AAA should contain which result code

    1. Hi Aman,

      Diameter Server can reply with diameter base protocol result-code then (DIAMETER_AUTHORIZATION_REJECTED 5003 User can not be authorized), along with Reply-Message AVP that contain reason of failure (Incorrect Username & Password)that is to be displayed to USER.

      Details as follow:
      The Reply-Message AVP (AVP Code 18) is of type UTF8String and contains text that MAY be displayed to the user. When used in an AA-Answer message with a successful Result-Code AVP, it indicates success. When found in an AAA message with a Result-Code other han DIAMETER_SUCCESS, the AVP contains a failure message.

      Hope we are inline with solution
      Thanks for your query.
      Happy to help you again.

    2. Thanks for your reply. So AAA would be sent with Result-Code other than DIAMETER_SUCCESS. It will contain Reply-Meassge AVP???