Re: [Sidrops] version negotiation

[Job Snijders <[e-mail]>]

On Mon, Mar 04, 2024 at 10:46:17AM -0800, Randy Bush wrote:
> >>> Now this changes the sematics of Error Code 4.  So Section 13 needs
> >>> to be adjusted. Error code 4 should not be fatal but have special
> >>> handling as described in Section 7. This is required because:
> >>>    Errors which are considered fatal MUST cause the session to be
> >>>    dropped, and the router MUST flush all data learned from that
> >>>    cache.
> >> 
> >> i am less sure of this.  note that is the session which must be
> >> dropped, not the transport.  and the session has not yet even been
> >> established if we're still negotiating versions.
> > 
> > I pondered more about this. I think your reason of "the session is not
> > yet established" does not matter here. What if the transport
> > connection was lost but the session and cache is all fine. When the
> > router starts a new connection and therefor MUST do the version
> > negotiation. The moment an Code 4 error pdu is received the RTR MUST
> > drop the database since Code 4 is a fatal error (it does not matter
> > that the session is not yet up).
> > 
> > Because of this interaction between various MUST in the draft it is
> > IMO necessary to make Error Code 4 non-fatal.
> 
> agree.  thanks.
> 
> i am about to push -12 with, i hope, all suggestions/corrections
> addressed.

This sentence reads slightly awkard, feels like a loose end:

    "A session is not [re-]established, but data learned need not be deleted."

perhaps:

    "A session is not yet [re-]established, any previously learned data
     need not be flushed for the time remaining in the Expire Interval."

Kind regards,

Job