+1 -----Original Message----- From: Eric Osborne (eosborne) [mailto:[email protected]] Sent: Monday, November 18, 2013 11:00 AM To: Jakob Heitz; UTTARO, JAMES Cc: Mingui Zhang; Stewart Bryant (stbryant); [email protected] Subject: RE: Why we consider the method of "label sharing for fast PE protection"
Oh, yeah. I'm not actually proposing that there's a workable solution. I'm trying to point out that there isn't one. The problem gets harder, too. PE1: VRF-A primary, VRF-B backup PE2: VRF-B primary, VRF-C backup PE3: VRF-C primary, VRF-A backup and so forth. eric > -----Original Message----- > From: Jakob Heitz [mailto:[email protected]] > Sent: Monday, November 18, 2013 10:57 AM > To: UTTARO, JAMES > Cc: Eric Osborne (eosborne); Mingui Zhang; Stewart Bryant (stbryant); > [email protected] > Subject: Re: Why we consider the method of "label sharing for fast PE > protection" > > "same algorithm" is not good enough on its own. If two routers using the > same algorithm boot up at different times and/or with different > neighbors, they still won't allocate the same labels. > > The algorithm cannot just be "same". It must be restricted in other > ways. > > -- > Jakob Heitz. > > > On Nov 18, 2013, at 5:51 AM, "UTTARO, JAMES" <[email protected]> wrote: > > > That sounds doable ;) > > > > -----Original Message----- > > From: [email protected] [mailto:[email protected]] On Behalf > Of Eric Osborne (eosborne) > > Sent: Monday, November 18, 2013 7:52 AM > > To: Mingui Zhang; Stewart Bryant (stbryant); Jakob Heitz; > [email protected] > > Subject: RE: Why we consider the method of "label sharing for fast PE > protection" > > > > It's not just the range, right? You have to allocate the same label > per VRF. So you either end up statically allocating labels or making > sure you have the same label allocation algorithm on every pair of > primary/backup PEs. > > > > > > > > > > > > eric > > > >> -----Original Message----- > >> From: [email protected] [mailto:[email protected]] On > Behalf > >> Of Mingui Zhang > >> Sent: Monday, November 18, 2013 4:34 AM > >> To: Stewart Bryant (stbryant); Jakob Heitz; [email protected] > >> Subject: RE: Why we consider the method of "label sharing for fast PE > >> protection" > >> > >> Hi Stewart, > >> > >> Operators can configure the PEs in an RG to reserve the same label > range > >> for sharing. > >> > >> With the ICCP connection established between the primary and backup > PE, > >> the primary PE can mandate the sharing label range out of the > >> intersection of the unused label space. > >> > >> Thanks, > >> Mingui > >> > >>> -----Original Message----- > >>> From: Stewart Bryant [mailto:[email protected]] > >>> Sent: Thursday, November 14, 2013 9:52 PM > >>> To: Jakob Heitz; Mingui Zhang; [email protected] > >>> Subject: Re: Why we consider the method of "label sharing for fast > PE > >>> protection" > >>> > >>> Isn't the normal problem that the two systems will be independently > >> allocating > >>> labels from their default label table, possibly with different > hardware > >> base and > >>> range, so there may not be a common label available that can be > >> allocated by > >>> both. > >>> > >>> - Stewart > >>> > >>> On 07/11/2013 21:50, Jakob Heitz wrote: > >>> > >>> > >>> Several people at the mike asked this question: > >>> How do you make sure that the PEs allocate the same label? > >>> > >>> This needs to be part of the document, because it is quite > >> important. > >>> If an external entity allocates the labels, the protocol > >>> between the PEs and that entity needs to be standardized. > >>> Since this is a feature that provides redundancy, the > >>> label allocating entity also needs to be backed up by a > >>> redundant entity. The protocol between the redundant > >>> label allocators needs to be standardized. > >>> > >>> > >>> > >>> -- > >>> > >>> Jakob Heitz. > >>> > >>> ________________________________ > >>> > >>> From: [email protected] [[email protected]] on behalf > of > >>> Mingui Zhang [[email protected]] > >>> Sent: Thursday, 07 November 2013 11:40 AM > >>> To: [email protected] > >>> Subject: Why we consider the method of "label sharing for fast PE > >>> protection" > >>> > >>> > >>> > >>> Hi, > >>> > >>> As a choice of fast PE protection, > >>> > >>> 1. This solution is simple and light-weight. We need not > introduce > >> the > >>> complex context label table in PE routers. So label table need not > be > >> stored > >>> repeatedly on RG members. > >>> > >>> > >>> 2. Also, it's easy to be deployed. It does not bring any change > to > >> P routers > >>> (control plane & data plane). It even does not change the data plane > of > >> PE > >>> routers. > >>> > >>> > >>> 3. In addition, it does not bear the restriction of "no > >>> penultimate-hop-popping". > >>> > >>> > >>> > >>> Thanks, > >>> Mingui > >>> > >>> > >>> > >>> > >>> -- > >>> For corporate legal information go to: > >>> > >>> http://www.cisco.com/web/about/doing_business/legal/cri/index.html > >
