We are on the same page.
I misinterpreted your :)

I guess it could be done at small scale with certain restrictions.
It's definitely not a generic solution.

--
Jakob Heitz.


On Nov 18, 2013, at 7:59 AM, "Eric Osborne (eosborne)" <[email protected]> 
wrote:

> 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
>>> 

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