> > > There is one problem with allowing ping in access phase only.
> > >
> > > Suppose both a PaC and a PAA are in access phase, and the PaC sends a
> > > ping request while the PAA sends a PAR to start re-authentication at
> > > the same time.  Then PAA will not accept the ping request because it
> > > has entered re-authentication phase.  If ping is allowed in any
> > > state, then PAA can answer to the ping request.
> >
> > I think the issue is about having two outstanding requests (one PANA-
> Ping
> > and one other) at the same time. The PAA (or PaC) having to respond to a
> > PANA-Ping-Request while it has an outstanding request shall not have a
> > problem. What do you think?
> 
> I think having two outstanding requests sent in different directions
> is acceptable.
> 
> >
> >
> > > BTW, I've found another issue here.  In the above example, The PaC
> > > will accept the PAR sent from the PAA and can return a PAN, but it
> > > cannot send a new PAR (this can happen if the PAN does not carry EAP),
> > > until the ping request is answered.  This is actually breaking
> > > lock-step behavior of PANA (queuing requests should not be required
> > > for a lock-step protocol).
> >
> > What would be the issue of having request queuing?
> 
> Queueing itself may not be an issue.  But the actual issues is the
> sender would need to distinguish two cases (i.e., if there is an
> outstanding ping request or not) for each state.
> 
> For example, supposed that the PaC is in a state waiting for a ping
> answer.  If another event that needs to send a PAR is generated, then
> the PaC processes the event, generates and queues a PAR and transits
> to a state that is waiting for a PAN, and it is still waiting for a

It should not transit to such state until the PAR is actually transmitted.
I'd say PAR (or the event that leads to PAR generation) shall be queued
until the PANA-Ping is completed (ping answer is received).


> ping answer.  This would require N*2 states (N is number of states
> except for ping, multiplied by 2 to consider whether there is a ping
> request or not.
> 
> >
> >
> > I'd like to see if we can avoid creating special case for PANA-Ping
> messages
> > (e.g., putting them under a separate treatment).
> 
> I think the only way to avoid it is:
> 
> - Allow sending ping request in access phase only.
> 


Makes sense.

> - Allow receiving ping request in any phase.

Makes sense.

> 
> - When there is an outstanding ping request, discard all incoming
> messages except for ping answer or error request sent in resopnse to
> the ping request.

If the PaC receives a PAR while waiting for a PANA-Ping-Answer, why should
it discard the PAR?

Alper






> 
> This may be an acceptable operation.
> 
> Yoshihiro Ohba
> 
> 
> >
> > Alper
> >
> >
> >


_______________________________________________
Pana mailing list
[email protected]
https://www1.ietf.org/mailman/listinfo/pana

Reply via email to