[dtn-interest] Re: [IRSG] POLL: draft-irtf-dtnrg-arch-07 -- DUE 30 Oct (Scott Burleigh)

[Michael Welzl <[e-mail]>]

> > On Nov 10, 2006, at 8:05 AM, Scott Burleigh wrote:
> >> Having selected, potentially hazardous BRLs time out and expire 
> >> sounds fine to me.  We absolutely do want to minimize the potential 
> >> for production of destructive traffic.
> >>
> >> I'm not quite so comfortable with the concept of pre-placing BRLs 
> >> along a path, in part because discovery of the path might be part of 
> >> the reason to establish the BRLs.  I can certainly see how one 
> >> wouldn't want BRLs for traffic-tracing BSRs installed at every node 
> >> in the network, and I wouldn't argue for that.  My notion is that the 
> >> subset of nodes at which we'd install some set of 
> >> mutually-referencing BRLs would be selected by whoever "owned" and/or 
> >> was responsible for network management at those nodes and was 
> >> interested in getting specific kinds of traffic handling information 
> >> from them.  Membership in the subset would be more a function of 
> >> administrative interest than of topology.
> >
> > It seems to me that the BRL is one of potentially several ways to 
> > limit the network impact of BSRs. And even with BRLs in place along 
> > the entire path, a node still cannot infer definitively that failure 
> > to receive a BSR means that the conditions requisite to generate the 
> > BSR did not occur, as the BSR may simply have been lost by the network 
> > en route to the report-to EID.
> >
> > I therefore propose that we change the architecture document to say 
> > that nodes "should" (not "must") generate BSRs in response to the 
> > specified conditions, and add a sentence or two explaining that 
> > various mechanisms to rate limit or suppress unwanted BSR generation 
> > may be in place at the node.
> >
> > Then the BRL mechanism can be individually specified in a separate 
> > draft as one of these mechanisms. In addition to specifying the format 
> > of the BRL and rules for the operation of the protocol, it could 
> > specify that a node which conforms to the BRL spec MUST generate a BSR 
> > when it has an appropriate BRL, thereby providing the additional 
> > assurance that the BSR was actually created.
> This seems fine to me.
> 
> Scott

Me, too.

Cheers,
Michael