Re: : ISSUE: Sections 4 & 5.10 appear to contradict each other

Glen Zorn (gwz) wrote:

> Description of issue: Self-contradictory text
> Submitter name: Glen Zorn
> Submitter email address: [email protected]
> Date first submitted: 17 Oct 05
> Document: sip
> Comment type: T
> Priority: S
> Sections: 4, 5.10
> Rationale/Explanation of issue: Sections 4 & 5.10 appear to contradict
> each other: Section 4 says "Central to the architecture is the fact that
> the user data is stored in a single point in the network.  This
> restriction does not mandate a particular implementation, e.g., it is
> possible to implement clusters of databases operating in mirror mode to
> provide redundancy.  The property required by this specification is that
> the user data the Diameter Server has access to is stored safely in what
> is seen, from the external point of view, as a single user database",
> but section 5.10 says (in describing the process of finding the correct
> Diameter server) "The Diameter SL, based on the contents of the SIP-AOR
> AVP and its own routing tables, determines the Diameter server that
> stores the information allocated to such user.  Then it builds a
> Diameter LIA message (step 3) that includes a Result-Code AVP set to
> DIAMETER_REDIRECT_INDICATION and one or more Redirect-Host AVPs, whose
> values are set to one or more URIs of Diameter servers that store the
> information related to such user.  Then the Diameter client in SIP
> server 1 builds a new LIR message (step 4) addressed to any of the
> Diameter servers received in the Redirect-Host AVPs".  It seems to me
> that either there is exactly one Diameter server that stores data
> pertaining to a given user or there is more than one.
> 
> Requested change: Make the document consistent; how this is done is up
> to the authors.
> 

I think you didn't read carefully, because I don't find the contradiction.

What we say is that the data ***pertaining to a given user *** is stored 
in a centralized point in the network (Diameter server). However, there 
can be a more than a single server, each one storing data for different 
users. So you may have Diameter server 1 that keeps the data for users 
1-100, Diameter server 2, that keeps the data for suers 101-200, and so on.

The purpose of the Diameter SL is to be a dispatcher towards the actual 
Diameter server that keeps the data related to a give user.

With this in mind, please propose text if something has to be clarified.

/Miguel
-- 
Miguel A. Garcia           tel:+358-50-4804586
sip:[email protected]
Nokia Research Center      Helsinki, Finland