Subject: [ANCP] ANCP behaviour for rate change

From: "Wojciech Dec (wdec)" <[email-masked]>
Date: Mon, 4 Feb 2008 17:46:29 +0100

Hi All,

I have a question about the expected behaviour of ANCP following
line-rate changes. At the same time I would request that this behaviour
be detailed in the appropriate drafts (Section 5.4.2 of protocol draft
would appear to be a reasonable place for this).

Let's say that a line rate initially comes up at rate X. This is
communicated in a Port-Up message.
Then, the line rate re-trains to rate Y. Is ANCP's expected behaviour
to:
a) Send a new Port-up with Rate Y
b) Send a Port-down followed by a Port-Up with rate Y.

Behaviour a) would IMO be highly preferable and described in the text.

Comments?

Regards,
Woj.

_______________________________________________
ANCP mailing list
[email-masked]
http://www.ietf.org/mailman/listinfo/ancp

---

From: "Haag, T" <[email-masked]>
Date: Wed, 6 Feb 2008 16:24:19 +0100

Hi Woj,

All explanations sound reasonable, but we are talking about an AN
implementation and not an ANCP protocol issue.

ANCP has to report the port status. That's the basic task of ANCP per
definition. 

Let me distinguish between two scenarios:

Scenario 1 Regular operation:

If line is up but line rate changes happen then option a) "Send a new
Port-up with Rate Y" is preferable.

Scenario 2 Fault condition:

If a port is toggling the AN has to integrate a certain period of time
the port status and to decide then if the port is up or down.

So the port has to send a port down message following the periodically
change between port up/down status. The period is determined by timer
value to be set by configuration. 

So this happens in option b) "Send a Port-down followed by a Port-Up
with rate Y".

Result:

Sending a port down message followed by a port up message is necessary
during resynchronisation in case of fault condition. IMO this is an
implementation issue of an AN. ANCP has to be prepared to support both
scenarios!

Regards

Thomas

________________________________

Von: Philippe Champagne (pchamp) [mailto:[email-masked]] 
Gesendet: Dienstag, 5. Februar 2008 16:58
An: Wojciech Dec (wdec); [email-masked]
Betreff: Re: [ANCP] ANCP behaviour for rate change

Hi Woj

I agree with (a) otherwise it implies twice as many messages

There is that part in section 5.4.2:

    The message SHOULD be generated when a line first comes UP, or any
of the 
     attributes of the line change e.g. the line re-trains to a
different 
     rate or one or more of the configured line attributes are 
     administratively modified.

So, it sounds like it is covering that. Is that what you were referring
to but to be worded more specifically? Or perhaps you missed this text
or I'm the one off track?

Regards

Phil

	
________________________________

	From: [email-masked] [mailto:[email-masked]] On
Behalf Of Wojciech Dec (wdec)
	Sent: Monday, February 04, 2008 11:46 AM
	To: [email-masked]
	Subject: [ANCP] ANCP behaviour for rate change

	Hi All, 

	Then, the line rate re-trains to rate Y. Is ANCP's expected
behaviour to: 

	Behaviour a) would IMO be highly preferable and described in the
text. 

	Comments? 

	Regards, 
	Woj.