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RE: [Softwires] BGP TE attr last call by softwires WG (2nd question)
>2) Every PE router in the IGP instance has L1VPN routes that
>it doesn't care about.
>
>3) The number of L1VPN routes that a given PE router doesn't
>care about is probably greater than the number of L1VPN routes
>it does care about.
>
>IB>> As I answered to Yakov if this proves to be a problem you can
>IB>> configure multiple overlays
JD: "With sufficient thrust, pigs fly just fine..." [RFC1295]
>
>Thanks,
>
>John
>
>>-----Original Message-----
>>From: Igor Bryskin [mailto:i_bryskin@yahoo.com]
>>Sent: Wednesday, September 03, 2008 6:47 AM
>>To: Drake, John E; Yakov Rekhter; Lou Berger
>>Cc: Yakov Rekhter; Adrian Farrel; ccamp@ops.ietf.org;
>>softwires@ietf.org
>>Subject: Re: [Softwires] BGP TE attr last call by softwires WG (2nd
>>question)
>>
>>And I am not arguing that sufficient redundancy must be provided.
>>However you said:
>>>For your suggested approach to work with sufficient redundancy, the
>>>topology of the overlay needs to be configured such that
>>every selected
>>>P router is connected to at least two other selected P routers and
>>>every PE router needs to be connected to at least two selected P
>>>routers.
>>
>>If you just simply interconnect all VPN-aware PEs into a single ring
>>via IPinIP tunnels and run an instance of OSPF to distribute
>>VPN-related information between them, it will provide sufficient
>>redundancy and involve exactly *zero* Ps.
>>So, I want you to drop your lecturing tone for a minute and
>simply tell
>>in what respect in your opinion this approach is not perfect fo the
>>L1VPN application. Otherwise, I am not interested in this discussion
>>any longer. I do like to hear comments from other people.
>>
>>Igor
>>
>>
>>
>>----- Original Message ----
>>From: "Drake, John E" <John.E.Drake2@boeing.com>
>>To: Igor Bryskin <i_bryskin@yahoo.com>; Yakov Rekhter
>><yakov@juniper.net>; Lou Berger <lberger@labn.net>
>>Cc: Yakov Rekhter <yakov@juniper.net>; Adrian Farrel
>><adrian@olddog.co.uk>; ccamp@ops.ietf.org; softwires@ietf.org
>>Sent: Wednesday, September 3, 2008 8:10:07 AM
>>Subject: RE: [Softwires] BGP TE attr last call by softwires WG (2nd
>>question)
>>
>>Igor,
>>
>>Actually, I am not sure that you do understand what I wrote, because
>>you are providing examples of the redundancy that I specified - every
>>PE router needs to have connectivity to two other routers in the IGP
>>instance.
>>
>>Thanks,
>>
>>John
>>
>>>-----Original Message-----
>>>From: Igor Bryskin [mailto:i_bryskin@yahoo.com]
>>>Sent: Tuesday, September 02, 2008 3:06 PM
>>>To: Drake, John E; Yakov Rekhter; Lou Berger
>>>Cc: Yakov Rekhter; Adrian Farrel; ccamp@ops.ietf.org;
>>>softwires@ietf.org
>>>Subject: Re: [Softwires] BGP TE attr last call by softwires WG (2nd
>>>question)
>>>
>>>Hi John,
>>>
>>>I understand what you are saying and disagree. The overlay I
>>am talking
>>>about logically is a separate network and as any network it
>should be
>>>sufficiently redundant to function. There is a number of
>ways how you
>>>can address the redundancy concerns. Look at the examples below:
>>>
>>>a) interconnect all VPN-aware PEs into a single ring:
>>>PE=======PE
>>> || ||
>>>PE PE
>>>|| ||
>>>PE PE
>>>|| ||
>>>... ....
>>>PE=======PE
>>>
>>>b) connect each PE to two interconnected Ps
>>>
>>>PE P PE
>>> ||
>>>PE || PE
>>> ||
>>>PE || PE
>>> ||
>>>... || ....
>>>PE P PE
>>>
>>>
>>>Note that tunnels can traverse any number of VPN-unaware Ps and PEs.
>>>
>>>Igor
>>>
>>>
>>>----- Original Message ----
>>>From: "Drake, John E" <John.E.Drake2@boeing.com>
>>>To: Igor Bryskin <i_bryskin@yahoo.com>; Yakov Rekhter
>>><yakov@juniper.net>; Lou Berger <lberger@labn.net>
>>>Cc: Yakov Rekhter <yakov@juniper.net>; Adrian Farrel
>>><adrian@olddog.co.uk>; ccamp@ops.ietf.org; softwires@ietf.org
>>>Sent: Tuesday, September 2, 2008 2:24:26 PM
>>>Subject: RE: [Softwires] BGP TE attr last call by softwires WG (2nd
>>>question)
>>>
>>>Igor,
>>>
>>>Several years ago when OSPF was first proposed as an autodiscovery
>>>mechanism for L1VPNs, you were told that it was a bad idea
>due to its
>>>scaling properties and impact on the IGP.
>>>
>>>You are now tacitly agreeing with those who told you it was a
>>bad idea.
>>>
>>>For your suggested approach to work with sufficient redundancy, the
>>>topology of the overlay needs to be configured such that
>>every selected
>>>P router is connected to at least two other selected P routers and
>>>every PE router needs to be connected to at least two selected P
>>>routers.
>>>
>>>When you are done with this configuration, you are left with a
>>>situation in which *every* PE and selected P router will have
>>>*all* L1VPN routes.
>>>
>>>Thanks,
>>>
>>>John
>>>
>>>>-----Original Message-----
>>>>From: Igor Bryskin [mailto:i_bryskin@yahoo.com]
>>>>Sent: Friday, August 29, 2008 12:10 PM
>>>>To: Drake, John E; Yakov Rekhter; Lou Berger
>>>>Cc: Yakov Rekhter; Adrian Farrel; ccamp@ops.ietf.org;
>>>>softwires@ietf.org
>>>>Subject: Re: [Softwires] BGP TE attr last call by softwires WG (2nd
>>>>question)
>>>>
>>>>Are you calling me silly? Are you coming to Minneapolis? :=)
>>>>
>>>>Seriously, what is wrong in your opinion with this approach?
>>>>Many people are talking about multi-instance IGPs. What
>they have in
>>>>mind is improving the IGP scalability:
>>>>a) by removing non-IP advertisements from the instance of IGP that
>>>>manages IP routing/forwarding tables into separate IGP instance(s);
>>>>b) by distributing non-IP information only to and via
>>>inerested parties
>>>>leaving the bulk of Ps out of the process.
>>>>
>>>>In my opinion this is exactly what is needed for the
>>OSPF-based L1VPN
>>>>application.
>>>>
>>>>Igor
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>----- Original Message ----
>>>>From: "Drake, John E" <John.E.Drake2@boeing.com>
>>>>To: Igor Bryskin <i_bryskin@yahoo.com>; Yakov Rekhter
>>>><yakov@juniper.net>; Lou Berger <lberger@labn.net>
>>>>Cc: Yakov Rekhter <yakov@juniper.net>; Adrian Farrel
>>>><adrian@olddog.co.uk>; ccamp@ops.ietf.org; softwires@ietf.org
>>>>Sent: Friday, August 29, 2008 2:31:36 PM
>>>>Subject: RE: [Softwires] BGP TE attr last call by softwires WG (2nd
>>>>question)
>>>>
>>>>So you are proposing an OSPF route reflector? At what point
>>does the
>>>>silliness stop?
>>>>
>>>>>-----Original Message-----
>>>>>From: Igor Bryskin [mailto:i_bryskin@yahoo.com]
>>>>>Sent: Friday, August 29, 2008 11:29 AM
>>>>>To: Drake, John E; Yakov Rekhter; Lou Berger
>>>>>Cc: Yakov Rekhter; Adrian Farrel; ccamp@ops.ietf.org;
>>>>>softwires@ietf.org
>>>>>Subject: Re: [Softwires] BGP TE attr last call by softwires WG (2nd
>>>>>question)
>>>>>
>>>>>Hi John,
>>>>>
>>>>>No, not really. When you add a PE you configure local
>>>>interfaces, local
>>>>>VPN port mappings, stuff like that. While doing this you will also
>>>>>configure an IPinIP tunnel to one of your spoke Ps and
>enable L1VPN
>>>>>OSPF instance on the tunnel.
>>>>>Once you did that the local VPN information will be flooded
>>>>accross the
>>>>>overlay, likewise, the new PE will get all the necessary
>>information
>>>>>from other PEs.
>>>>>
>>>>>Cheers,
>>>>>Igor
>>>>>
>>>>>
>>>>>----- Original Message ----
>>>>>From: "Drake, John E" <John.E.Drake2@boeing.com>
>>>>>To: Igor Bryskin <i_bryskin@yahoo.com>; Yakov Rekhter
>>>>><yakov@juniper.net>; Lou Berger <lberger@labn.net>
>>>>>Cc: Yakov Rekhter <yakov@juniper.net>; Adrian Farrel
>>>>><adrian@olddog.co.uk>; ccamp@ops.ietf.org; softwires@ietf.org
>>>>>Sent: Friday, August 29, 2008 11:20:16 AM
>>>>>Subject: RE: [Softwires] BGP TE attr last call by softwires WG (2nd
>>>>>question)
>>>>>
>>>>>Igor,
>>>>>
>>>>>Doesn't this defeat auto-discovery? I.e., how is a new PE
>>>added to a
>>>>>given L1VPN?
>>>>>
>>>>>Thanks,
>>>>>
>>>>>John
>>>>>
>>>>>>-----Original Message-----
>>>>>>From: Igor Bryskin [mailto:i_bryskin@yahoo.com]
>>>>>>Sent: Friday, August 29, 2008 5:51 AM
>>>>>>To: Yakov Rekhter; Lou Berger
>>>>>>Cc: Yakov Rekhter; Adrian Farrel; ccamp@ops.ietf.org;
>>>>>>softwires@ietf.org
>>>>>>Subject: Re: [Softwires] BGP TE attr last call by
>softwires WG (2nd
>>>>>>question)
>>>>>>
>>>>>>Yakov,
>>>>>>
>>>>>>You said:
>>>>>>
>>>>>>
>>>>>>... And while on the subject of scaling, please keep in mind
>>>>that BGP
>>>>>>only stores L1VPN routes on PEs that have sites of that VPN
>>>>connected
>>>>>>to them, and on an RR if used, but *not* on any of the P
>>>routers. In
>>>>>>contrast, rfc5252 (OSPF for L1VPN
>>>>>>autodiscovery) results in storing *all VPN TE information
>>>for all the
>>>>>>VPNs* on *all* the IGP nodes, both P and PE. So, clearly
>BGP-based
>>>>>>approach scales better than OSPF-based approach.
>>>>>>
>>>>>>Yakov.
>>>>>>
>>>>>>This is not true in case of multi-instance OSPF: one can build an
>>>>>>overlay interconnecting PEs via one or small number of Ps
>>>>>using IPinIP
>>>>>>tunnels and run in this overlay an instance of OSPF specifically
>>>>>>designated for distribution of L1VPN information. In this
>>>>>case the OSPF
>>>>>>solution won't scale any worse than the BGP approach. Note.
>>>>>that rfc252
>>>>>>never said that the instance of OSPF used for flooding of
>>the L1VPN
>>>>>>information must be the same instance that is used for the
>>>>>distribution
>>>>>>of IP-related LSAs.
>>>>>>
>>>>>>Regards,
>>>>>>Igor
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>
>>>>
>>>>
>>>
>>>
>>>
>>>
>>
>>
>>
>>
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