Re: WG last calls

["Adrian Farrel" <adrian@olddog.co.uk>]

Hi Zhang,

There is certainly nothing to prevent your suggestion.

This would be an implementation choice, although an operator would
probably want to configure identical behavior on all crankback-capable
LSRs in the network.

Adrian
----- Original Message ----- 
From: "Zhang Renhai" <zhangrenhai@huawei.com>
To: "Adrian Farrel" <adrian@olddog.co.uk>
Cc: "Ash, Gerald R (Jerry), ALABS" <gash@att.com>; <ccamp@ops.ietf.org>
Sent: Monday, April 04, 2005 9:51 AM
Subject: Re: WG last calls


> Hi, Adrian
> In RFC 3209,LSP is provided with attribute of  Priority(Setup
Priority,Holding Priority),
> so it is more reasonable to  process different LSPs according to the
Priority, for the LSP
> with higher priority, more retry number should be given, lower priority
with less number.
> Extremely, to the highest LSP, can the interception be concelled by
ABR?(although multi LSPs
> may be derived simultaneously, sellection can be done by egress on
receiving Path massege
> .So we can get another LSP with most possibility because of its highest
priority)
>
> Just my suggestion.
>
> Regard,
> Zhang
>
>
> ----- Original Message ----- 
> From: "Adrian Farrel" <adrian@olddog.co.uk>
> To: "Ash, Gerald R (Jerry), ALABS" <gash@att.com>; "Zhang Renhai"
<zhangrenhai@huawei.com>; <ccamp@ops.ietf.org>; "Kireeti Kompella"
<kireeti@juniper.net>
> Cc: "Ash, Gerald R (Jerry), ALABS" <gash@att.com>
> Sent: Sunday, April 03, 2005 1:05 AM
> Subject: Re: WG last calls
>
>
> > Hi,
> >
> > Yes, to clarify what Jerry says, the number of crankback attempts MAY
be
> > limited. At the moment, the only way that we provide to limit the
attempts
> > is implemented per LSR. That is, any LSR MAY decide that it has
performed
> > enough attempts at rerouting and pass the error back to the upstream
LSR.
> >
> > Note that the use of crankback to derive a path through a network is
not
> > recommended. This approach is almost equivalent to random walk routing
and
> > is neither efficient nor effective.
> >
> > The use of crankback, as described in the draft is intended for use in
> > specific circumstances, such as inter-domain routing. In these cases
only
> > selective LSRs (such as domain boundaries) perform rerouting attempts.
> >
> > Adrian
> >
> > ----- Original Message ----- 
> > From: "Ash, Gerald R (Jerry), ALABS" <gash@att.com>
> > To: "Zhang Renhai" <zhangrenhai@huawei.com>; "Adrian Farrel"
> > <adrian@olddog.co.uk>; <ccamp@ops.ietf.org>; "Kireeti Kompella"
> > <kireeti@juniper.net>
> > Cc: "Ash, Gerald R (Jerry), ALABS" <gash@att.com>
> > Sent: Friday, April 01, 2005 2:02 PM
> > Subject: RE: WG last calls
> >
> >
> > Zhang,
> >
> > > From draft-ietf-ccamp-crankback-04.txt ,section 4.5, the
> > > number of crankback rerouting is limited, so there will
> > > be a result: there is another LSP,but for the reason of
> > > limiting, the path may be not found.  I think sometimes
> > > it is unacceptable.The LSP may be prefered to enhancing
> > > performance.
> >
> > This problem can be avoided by the setting the node retry threshold
> > (configurable per node) very high (~infinity), so retries aren't
> > limited.
> >
> > Thanks,
> > Jerry
> >
> >
> >
> >
>
>
>