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RE: [EFM] About OAM TLVs


After your and John's explanation, I understand completely its intended use
now. Thanks!

By the way, if anyone is defining some private OAM functionality that is
negotiated through this OUI mechanism, I am interested in participating in
and supporting it in our product.

Yonghong Ren
Appian Communications

-----Original Message-----
From: Matt Squire []
Sent: Thursday, August 14, 2003 11:16 AM
To: John Messenger; Yonghong Ren;
Subject: RE: [EFM] About OAM TLVs

Additionally, to the question of why duplicate the OUI, the idea is that the
OUI in the different uses does not have to be the same.  In the information
PDU, it identifies the vendor of the equipment.  Some other
organization/company (ITU, MetroEthernetForum, CompanyX, etc.) may define
events that multiple vendors wish to use.  So different OUIs are required.

- Matt

> -----Original Message-----
> From: John Messenger []
> Sent: Monday, August 11, 2003 5:41 AM
> To: 'Yonghong Ren'; ''
> Subject: RE: [EFM] About OAM TLVs
> Hi,
> I asked for the org-specific information TLV (to be included 
> optionally in
> Information OAMPDUs).  We already had an org-specific event 
> TLV (for Event
> OAMPDUs) and org-specific OAMPDUs in general, and the 
> org-specific info TLV
> completes the set.  As an example, it can be used during the 
> discovery phase
> to negotiate vendor-specific extensions - as no other OAMPDUs can be
> exchanged during this phase, this is the only way to achieve such
> negotiation.
> With regard to its content, the meaning of the OUI in the 
> org-specific TLV
> is to define the interpretation of the remaining part of the 
> TLV, and it
> says nothing about the organisation making the device which sends or
> receives it.  So as a vendor, I might define OAM extensions 
> and tell you
> what they were so that you could use them too, as a value-add 
> to both our
> products, or for industry groups to enhance the protocol and 
> still remain
> within the standard.  
> I hope this satisfactorarily explains the reasoning behind 
> this extension.
> Regards,
> 	-- John
> --
> John Messenger (
> R&D Software Manager, ADVA Optical Networking Ltd.
> Tel: +44-1904 699309   Fax: +44-1904 699378
> "Mind like parachute - only work when open" (Charlie Chan) 
> -----Original Message-----
> From: Yonghong Ren []
> Sent: 07 August 2003 19:56
> To: ''
> Subject: [EFM] About OAM TLVs
> 1.  The most recent draft (2D) defines "Organization Specific 
> Information
> TLV".  It contains OUI, which is also incuded in the mandatory Local
> Information TLV's Vendor Identifier. Why the duplication? 
> Taking up extra 3
> bytes is not an issue, but it opens up the question of how to 
> interpret if
> it's different from that in Local Information TLV. If they 
> are supposed to
> be same, then we have to enforce it.
> 2. Currently this Organization Specific Information TLV can 
> only be included
> in Information PDU, which I think limits its usefulness. 
> I would propose a generic organization specific TLV that is 
> allowed to be
> included in all PDUs except Variable Request and Responsel. 
> Doing so helps
> make OAM more useful. For example, when sending dying gasp, 
> an vendor could
> include a private TLV that explains what caused the dying gasp.
> Appreciate any comments. Thanks.
> Yonghong Ren
> Appian Communications