RE: Two Drafts for Resilience of Control Plane

[<neil.2.harrison@bt.com>]

To add.....

There are some fairly significant differences between cl-ps mode, co-ps
mode and co-cs mode networks.  Indeed, in the co-cs mode an OOB
control/management *network* is a forced solution.  And note there are
(at least) 2 different networks in the same networking system....and how
one addresses resilience for these 2 networks is quite different.  In
fact because the control/management plane network is so important it
should only ever take its design cues from the duct topology.  And there
are other ways to deal with resilience other than 'an IGP' here, cf the
link-set in C7 (which btw is a cl-ps OOB network) as used in the
PSTN..........don't knock it, its a very simple and excellent
idea....maybe a researcher should look at it for some inspiration ;-)

regards, Neil

> -----Original Message-----
> From: owner-ccamp@ops.ietf.org
> [mailto:owner-ccamp@ops.ietf.org] On Behalf Of Igor Bryskin
> Sent: 28 October 2005 16:50
> To: Zafar Ali (zali); Kim Young Hwa; ccamp@ops.ietf.org
> Subject: RE: Two Drafts for Resilience of Control Plane
> 
> 
> Zafar,
> 
> The problem arises when the control plane is decoupled
> from the data plane. The question is do we need such decoupling in IP 
> networks? Consider, for example, the situation when several parallel 
> PSC data links bundled together and controlled by a single control 
> channel. Does it mean in this case that when the control
> channel fails all associated data links also fail? Do
> we need to reroute in this case LSPs that use the data
> links? Can we rely in this case on control plane
> indications to decide whether an associated data link
> is healthy or not (in other words, can we rely on RSVP
> Hellos or should we use, for example, BTD)? Should we
> be capable to recover control channels without
> disturbing data plane? I think control plane
> resilience is important for all layers. You are right,
> Internet does work, however, we do need for some
> reason TE and (fast) recovery in IP as much as in
> other layers,don't we?
> 
> Cheers,
> Igor
> 
> --- "Zafar Ali (zali)" <zali@cisco.com> wrote:
> 
> > Hi All,
> >  
> > I am unable to understand the problem we are trying
> > to solve or
> > fabricate. My control network is IP based and IP has
> > proven resiliency
> > (Internet *does* work), why would I like to take
> > control plan resiliency
> > problem at a layer *above-IP* and complicate my
> > life. Did I miss
> > something?
> >  
> > Thanks
> >  
> > Regards... Zafar
> > 
> > 
> > ________________________________
> > 
> > 	From: owner-ccamp@ops.ietf.org [mailto:owner-ccamp@ops.ietf.org]
On 
> > Behalf Of Kim Young Hwa
> > 	Sent: Friday, October 28, 2005 6:04 AM
> > 	To: ccamp@ops.ietf.org
> > 	Subject: Two Drafts for Resilience of Control Plane
> > 	
> > 	
> > 	Dear all,
> > 	 
> > 	I posted two drafts for the resilience of control
> > plane.
> > 	One is for requirements of the resilience of
> > control plane, the
> > other is for a protocol specification as a solution
> > of that .
> > 	These are now available at:
> > 	
> >
> http://www.ietf.org/internet-drafts/draft-kim-ccamp-cpr-reqts-01.txt
> > 	
> >
> http://www.ietf.org/internet-drafts/draft-kim-ccamp-accp-proto
col-00.txt
> 	 
> 	I want your comments.
> 	 
> 	Regards
> 	 
> 	Young.
> 	 
> 	====================================
> 	Young-Hwa Kim
> 	Principal Member / Ph.D
> 	BcN Research Division, ETRI
> 	Tel:     +82-42-860-5819
> 	Fax:    +82-42-860-5440
> 	e-mail: yhwkim@etri.re.kr
> 	====================================
> 	
>
<http://umail.etri.re.kr/External_ReadCheck.aspx?email=ccamp@ops.ietf.or
>
g&name=ccamp%40ops.ietf.org&fromemail=yhwkim@etri.re.kr&messageid=%3C863
> 0a6db-0c31-49ab-a798-13b0dda04553@etri.re.kr%3E>
> 
> 



	
		
__________________________________ 
Yahoo! Mail - PC Magazine Editors' Choice 2005 
http://mail.yahoo.com