FW: LMP Related Questions - 2

[Harish M <harishm@huawei.com>]

Thanks Richard, for correcting the last point.

 

 

-----Original Message-----
From: Bradford, Richard [mailto:rbradfor@cisco.com]
Sent: Wednesday, December 08, 2004 5:40 PM
To: harishm@huawei.com
Subject: RE: LMP Related Questions - 2

At 03:49 PM 12/8/2004 +0530, you 
wrote:
> Hi,
>  
> A node can send BeginVerify message (if Link Connectivity 
>   Verification procedure is supported) before starting Link Property Correlation 
>   Procedure.
> Remote node if it does not support Link Connectivity Verification 
>   procedure, it shall send BeginVerifyNack with ERROR_CODE: 0x01 (Procedure Not 
>   supported).
Agreed.

>  Link Connectivity Verification procedure can be used for 
>   Learning (automatic discovery) of LinkID (of remote node) & have the 
>   mapping of InterfaceIDs with itself & remote 
> node.
Agreed,

> If this 
>   procedure is not used, then adminstrator should configure mapping of LinkID 
>   & InterfaceIDs with neighbor node before triggering "Link Property 
>   Correlation"
Agreed.

> And 
>   also, in Link Connectivity Verification procedure, as the LinkID is optional 
>   parameter in BeginVerifyAck, if the initiatior does not receive this, then 
>   administrator should configure the mapping of LinkIDs (Local & Remote Link 
>   ID)
This doesn't seem entirely accurate. The reason that the 
LinkID is not required in the BeginVerifyAck is that it may not yet have been 
discovered. If the mapping is not configured, then the mapping will be 
discovered upon receipt of a Test message, which occurs later in the procedure 
than the BeginVerifyAck. In this case, the initiator learns the mapping from the 
TestStatusSuccess message.
So, it's only necessary to configure the mapping 
of LinkIDs if Link Connectivity Verification fails and is not dependent on the 
contents of the BeginVerifyAck.

Hope this 
helps,
   Rich

Regards,
Harish
 

-----Original Message-----

From: owner-ccamp@ops.ietf.org [mailto:owner-ccamp@ops.ietf.org]On Behalf Of Kim Young Hwa

Sent: Wednesday, December 08, 2004 1:59 PM

To: ccamp@ops.ietf.org

Subject: LMP Related Questions - 2

Hi, ccampers

Because some give me different responses, but increasingly I'm in a mess.

Then, I've some questions as follows:

(1) When receiving BeginVerify message, the node will first check if "link verification supported" flag is set. However, this flag is set in a TE-Link object of LinkSummary message. Without the flag set, the remote node must send BeginVerifyNack message. Why do we send "link connectivity verification" messages before "link property correlation" messages?

(2) BeginVerify can contain Local-Link-ID without Remote-Link-ID. Without link property correlation, the remote node has no mapping between two Link-IDs. How can the remote node identify which TE links to be verified?

Thanks,

Young.