eap Mailing List: Re: Ordered delivery of EAP messages

[Glen Zorn (gwz) (gwz]

Alper Yegin <> allegedly scribbled on Tuesday, March 06, 2007 3:25 PM:

>> Both EAP and RADIUS do not detect duplicates arriving out of order;
>> they depend on the underlying lower layer to provide in-order
>> delivery so as to enable duplicate detection.
> 
> RFC 2865 says:
> 
>       The RADIUS server can detect a duplicate request if
>       it has the same client source IP address and source UDP port and
>       Identifier within a short span of time.
> 
> This, to me, implies duplicate detection on the server side does not
> rely on orderly delivery. Keeping the history for "a short span of
> time" allows duplicate detection irrespective of the order the
> requests come in.   

Agree.

> 
> As for the responses... Assuming the RADIUS client transmitted a
> request twice (first one timed out), if it receives one of the
> responses, would it still accept the second (duplicate) response if
> it arrives as well? Wouldn't the RADIUS client just drop the second
> response because there is no outstanding request to match anymore?  

Seems reasonable.  So why wouldn't this reasoning apply to EAP as well?
  
> 
> 
> Alper