The MPLS WG Archive

[Shahram Davari <Shahram_Davari@pmc-sierra.com>]

Eric,

May be. I think ITU should decide about that.

-Shahram

> -----Original Message-----
> From: Eric Gray [mailto:eric.gray@sandburst.com]
> Sent: Thursday, March 21, 2002 12:19 PM
> To: Shahram Davari
> Cc: 'Thomas D. Nadeau'; 'George Swallow'; 'mpls@uu.net'
> Subject: Re: Y.1711 requirements from IETF
> 
> 
> Shahram,
> 
>     Ah!
> 
>     I understand that it can be quite frustrating to realize that you
> could have done less work.  Might it not be easier in the long
> run to revert to the simpler version?
> 
> You wrote:
> 
> >Eric,
> >
> >I didn't quite catch your question. If you are asking about 
> the 1/s transmission of CV,
> >then there are 2 choices in general:
> >
> >1) define one rate and define a globally accepted definition 
> of the availability and unavailability state and the
> >condition for their transitions. This guarantees 
> interoperability and global SLA measurement.
> >
> >2) Don't specify any rate or availability and unavailability 
> states and the transition conditions.
> >
> >Each has its advantage and disadvantage. They are two 
> different approaches. Some like to buy a car with ABS some 
> like to buy a car without ABS which are cheaper.
> >
> >In fact it would have been much easier for us to not specify 
> any rate, availability and state diagrams in Y.1711 and 
> reduce it to only 2-3 pages.
> >
> >-Shahram
> >
> >>-----Original Message-----
> >>From: Eric Gray [mailto:eric.gray@sandburst.com]
> >>Sent: Thursday, March 21, 2002 12:01 PM
> >>To: Shahram Davari
> >>Cc: 'Thomas D. Nadeau'; 'George Swallow'; 'mpls@uu.net'
> >>Subject: Re: Y.1711 requirements from IETF
> >>
> >>
> >>Shahram,
> >>
> >>    Speaking strictly as an individual, I do not understand 
> what your 
> >>reasons
> >>are for being quite so immovable on this topic.  Can you 
> >>explain why it 
> >>is that
> >>you feel it is so important to use (or at least not to change) the 
> >>current words?
> >>
> >>You wrote:
> >>
> >>>Sure, but then what is your fault detection time scale, and 
> >>>
> >>how do you measure availability SLA?
> >>
> >>>-Shahram
> >>>
> >>>>-----Original Message-----
> >>>>From: Thomas D. Nadeau [mailto:tnadeau@cisco.com]
> >>>>Sent: Thursday, March 21, 2002 11:17 AM
> >>>>To: Shahram Davari
> >>>>Cc: 'George Swallow'; 'mpls@uu.net'
> >>>>Subject: RE: Y.1711 requirements from IETF 
> >>>>
> >>>>
> >>>>
> >>>>        Well, you MAY LSP ping all of those FECs if you 
> wish and at
> >>>>whatever rate you (i.e.: an operator) feels comfortable 
> with. No one
> >>>>is "strongly suggesting" that you do so at 1 packet per second.
> >>>>
> >>>>        --Tom
> >>>>
> >>>>
> >>>>>But the same is true for MPLS-ping. You also need to ping 
> >>>>>
> >>>>all those FECs.
> >>>>
> >>>>>-Shahram
> >>>>>
> >>>>>>-----Original Message-----
> >>>>>>From: George Swallow [mailto:swallow@cisco.com]
> >>>>>>Sent: Wednesday, March 20, 2002 5:59 PM
> >>>>>>To: Shahram Davari
> >>>>>>Cc: 'Thomas D. Nadeau'; 'mpls@uu.net'; swallow@cisco.com
> >>>>>>Subject: Re: Y.1711 requirements from IETF
> >>>>>>
> >>>>>>
> >>>>>>>Where did you get this " ALL LSPs MUST" statement from? May
> >>>>>>>
> >>>>>>be you are
> >>>>>>
> >>>>>>>reading a different Y.1711 than I have. All I can find are
> >>>>>>>
> >>>>>>the following
> >>>>>>
> >>>>>>>statement:
> >>>>>>>
> >>>>>>>" ... It is strongly recommended that CV OAM packets be
> >>>>>>>
> >>>>>>generated on all LSPs
> >>>>>>
> >>>>>>>(in order to detect all defects and potentially provide
> >>>>>>>
> >>>>>>protection against
> >>>>>>
> >>>>>>>traffic leakage both in and out of LSPs). "
> >>>>>>>
> >>>>>>I have one customer providing an IP VPN service who has >1500 PE
> >>>>>>routers and probably well over a million LSPs.  Most of the LSPs
> >>>>>>represent VPN connectivity can carry very little traffic.
> >>>>>>
> >>>>>>Would you "strongly recommend" that CV OAM packets be 
> >>>>>>
> >>>>generated on all
> >>>>
> >>>>>>their LSPs at a rate of 1 per second?  Can you point to *any*
> >>>>>>currently deployed network other than those using MPLS 
> solely for
> >>>>>>traffic engineering where this would be a good idea?  If 
> >>>>>>
> >>>>I'm carrying
> >>>>
> >>>>>>the full internet routing table and using LDP downstream 
> >>>>>>
> >>>>unsolicited
> >>>>
> >>>>>>should every router generate 108,000 (the current number 
> >>>>>>
> >>>>of routes) CV
> >>>>
> >>>>>>OAM packets per second?
> >>>>>>
> >>>>>>Perhaps you should revisit this "strongly recommended"
> >>>>>>recommendation.  Perhaps you should provide for 
> >>>>>>
> >>>>generation of CV OAM
> >>>>
> >>>>>>packets at rates other than 1  second.
> >>>>>>
> >>>>>>...George
> >>>>>>
> >>>>>>========================================================
> ==========
> >>>>>>George Swallow       Cisco Systems                  
> (978) 497-8143
> >>>>>>                    250 Apollo Drive
> >>>>>>                    Chelmsford, Ma 01824
> >>>>>>
> >>>>
> >>>>--------------------------------------------------------------
> >>>>----------
> >>>>Mathematics is the supreme nostalgia of our time. 
> >>>>
> >>>
> >>
> >>
> >
> 
> 
>