Subject: [AAA-WG]: [Issue] Diameter introduction needs improvement

From: Bernard Aboba <[email-masked]>
Date: Sat, 29 Dec 2001 09:16:16 -0800 (PST)

Note: this issue never got entered into the issues list, so it is being
resubmitted. 

Description of issue: Diameter introduction needs improvement

Submitter name: Randy Bush
Submitter email address: [email-masked] 
Date first submitted: 2001.09.03
Reference: 
Document: base
Comment type: E 
Priority: S 
Section: 1.0, 1.1
Rationale/Explanation of issue: 

The Introduction (section 1.0) talks about the history and motivation for
the development of Diameter. Section 1.1 talks about the basic building
blocks of Diameter. Section 2 provides an overview of protocol
concepts. What would be helpful is if a high-level introduction could be
provided within section 1. The material currently in section 1.1 might be
better moved to section 2.

Requested change: 

To provide context, the following topics would be useful in the
Introduction:
     
     a. An overview of the Diameter approach
            1. Relationship of NASes, Servers and Intermediaries
            2. Message routing concepts
            3. Requests, Responses, Unsolicited messages

     b. Important ways that Diameter differs from RADIUS
        (Idea is to introduce the concepts, not go into
         depth, but make clear what the feature is attempting
         to achieve. Reference where details are provided.)
            1. Peer-to-peer nature
            2. Explicit support for intermediaries
            3. Connection-oriented versus connectionless
            4. Concept of extensions
            5. Built-in failover support
            6. Larger attribute space 
            7. Integrated accounting
            8. Mandatory bit
            9. Application-layer ACKs and error messages
           10. Unsolicited server messages
           11. Peer discovery
           12. Capabilities negotiation (worth explaining why
               this isn't e2e here)

     c. Description of the Diameter document set and relationship
        between the documents.
 
     d. Approach to extensibility (this is in section 2.3, but might
        be better consolidated into the Introduction)