The MPLS WG Archive

["Ash, Gerald R (Jerry), ALABS" <gash@att.com>]

Tom,

> the MIBs need to be wrapped up ASAP and ...
> we are well on this track.

Good, hopefully by IETF-57, in order to avoid 'sending them to the dust-bin' as Bert has suggested.

> To address your statement about requirements,
> as discussed previously offline with yourself
> and the MIB co-authors, 

There is about a one-year history/archive of posts to the lists regarding these requirements.

> many of the requirements you listed below require 
> changes to the LDP protocol itself. 

Which of the 3 LDP requirements constitute 'many' that need LDP changes?  

Obviously we're not proposing LDP protocol changes.  Also, the requirements I-D does not propose specific MIB extensions, *in order to avoid past discussions of why specific extensions won't work*.  Step-1 is to make sure the requirements are understood, and then step-2 is to decide how to meet them.  

Joan has suggested (I believe for requirements R1 and R2) 'a MIB which stores LDP counter information in a history table'.  That's a step-2 in the right direction.  Furthermore, Adrian has suggested that 'instances of entities' is a concept that has been handled in MIBs before and could be added in an optional way so that implementations did not have to maintain persistent information, but can choose to.

As to R3, it should be clear, a MIB should be straightforward.
 
> I suggest that you consult with 
> other SPs in the WG on these requirements to make sure 
> that they are consistent. I personally have not been hearing 
> any of these requirements from other SPs that participate
> in the MPLS WG.  

So that signifies the death-knell pronouncement from the self-appointed OAM/MIB-czar?  Perhaps the famous 25 pro-VCCV SPs you often quote (but who never speak for themselves) can attest to the MPLS-MIBs perfection/no-more-requirements-needed?

There has been no opposition to the requirements R1-R5 we've been stating for a long time (except, consistently, from you).  

> I suggest that you direct your requirements to the 
> authors of the LDP specifications and propose 
> extensions/additions there first because the MIBs 
> cannot manage what the protocols will not provide. 

We're not proposing any changes to LDP.  As above, Joan is suggesting approaches to R1 & R2.  R3 clearly requires no protocol changes.

> The remaining requirements you listed 
> below apply specifically to the PPVPN-MPLS-VPN MIB and not
> to the base MPLS MIBs which are in WG last call presently.

R3 and R4 need to be addressed, have been there a long time, and do not have to wait until last call to be discussed/progressed.

Jerry

> -----Original Message-----
> From: Ash, Gerald R (Jerry), ALABS [mailto:gash@att.com] 
> Sent: Wednesday, June 18, 2003 1:43 PM
> To: Wijnen, Bert (Bert); Loa Andersson; MPLS WG
> Cc: Ash, Gerald R (Jerry), ALABS; Lai, Wai S (Waisum), ALABS; 
> Chung, Li-Jin W, ALABS; ppvpn@nortelnetworks.com
> Subject: RE: WG last call on LSR and LDP MIB modules - setting dates
> 
> 
> Bert, Loa, All,
> 
> I'd like to follow up on Wai Sum's comments below, and 
> encourage that high-priority MPLS-MIB problems/requirements 
> identified through extensive testing be addressed in the MPLS 
> MIB modules.
> 
> The MPLS MIB problems/requirements are identified in 
> http://ietf.org/internet-drafts/draft-lai-mpls-mib-rqmts-00.txt, 
> and are critical operator requirements stemming from 
> detailed lab testing by Li Chung and others at AT&T.  
> MPLS-VPNs aren't going to operate as well as needed until and 
> unless these requirements are met.  It is expected that 
> operators wishing to use the same MPLS MIBs would have 
> similar concerns.
> 
> The I-D does not propose specific MIB extensions based on the 
> requirements.  Rather, such extensions are left to the MIB 
> designers, in order to avoid past discussions of why specific 
> extensions won't work.  But so far there is no help or 
> response from MIB designers on how to meet the requirements, 
> even though the problems have been identified on email lists 
> for more than one year. 
> 
> Here is a summary of requirements (R1,R2,R3 LDP related; 
> R4,R5 VPN related):
> 
> R1. It is required to capture the signaling usage/performance 
> of the LDP Entities, as well as the traffic usage/performance 
> of the LDP Sessions. R2. It is required to ensure persistency 
> of information in the LDP-MIB Entity Table and Entity 
> Statistics Table, whenever an LDP Entity is disabled and then 
> re-enabled. R3. It is required that a count be reported of 
> mplsNumVrfRouteMaxThreshExceeded notification when the 
> operator-defined VRF maximum route threshold is exceeded. R4. 
> It is required to have an explicit mapping between VRF, RD, 
> and RT in the mplsVpnVrfRouteTargetTable table. R5. It is 
> required to track the number of BGP prefixes on the PE-CE 
> link, and that the BGP neighbor maximum-prefix limit on the 
> PE-CE link be used to limit the number of eBGP routes 
> injected in the VRF.
> 
> I agree with Harmen Van der Linde, "We need to get this MPLS 
> MIB module, together with the MPLS LDP and MPLS VPN modules, 
> standardized ASAP. There is a critical need for these MPLS 
> MIB modules for management of MPLS-enabled networks, which 
> are currently being deployed by many service providers."
> 
> Bert threatened at IETF-56 to start over on MPLS MIBs if not 
> finished by IETF-57.
> 
> We need the MPLS MIB designers to meet critical requirements 
> and complete ASAP.
> 
> Thanks,
> Jerry