On 2/20/08, David Schwartz <[EMAIL PROTECTED]> wrote:
>
>
> > But, the application code tries to clear out/shutdown existing
> > SSL session with orderly bi-directional alerts. Once shutdown it
> > creates a new SSL object 'ssl' [ssl = SSL_new (ctx)]
> > for the next session in persistent connection..
>
> This is nearly impossible to do. It's possible that you did it correctly,
> but very unlikely. The basic problem is this -- when you call 'read' to
> get
> the last message of the first session, how do you make sure you also don't
> get all or part of the first message of the second session?
>

   I do not think   it is very difficult. The application initiates SSL
sessions sequentially in a established socket connection.One cycle of
SSL_connect - DataExchange-SSL_shutdown is followed by another cycle of
SSL_connect - DataExchange-SSL_shutdown. As such there shouldn't be issue of
session mix up.At least that is what is observed with say 400-500 clients
connecting to server simultaneously.

>
> > When the app simulates limited clients , say, 100, each client makes
> > hundreds of  unique SSL sessions successfully in persistent connection.
> > It is under stress of ~800 clients , that I run into issues.
> > Also, the bi-directional alerts do not happen always under
> > high stress..could this be the reason? a possible session data mix up?
>
> Either your code properly separates the sessions or it doesn't. My bet is
> that it doesn't because this is very hard to do right.
>

 Yes. I believe so..I am able to establish hundreds of cycles of new
sessions in persistent connection. The trouble is under high stress sessions
fail as indicated by ethereal trace.Sometimes server complains of Bad_MAC
error on receiving Finished message from client.

>
> Why do you do things this way? It's just plain wrong. Either layer on top
> of
> SSL or don't, but splitting the difference and "sort of" layering between
> SSL and TCP is just plain crazy.


   Multiple sessions are tried in a single TCP connect to reduce the
overhead of TCP handshake and termination if the client wishes to do
multiple 'new' SSL connects to server.


Thanks,
Prabhu. S


>
>
> DS
>
>
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