Subject: RE: Question on RSVP LSP Tunnel Spec

From: K Arvind <[email-masked]>
Date: Thu, 26 Aug 1999 10:44:19 -0400

Lou,

Doesn't the proposed Class-of-Service SENDER_TSPEC object take away the 
ability for the tunnel head end node to convey traffic rate information 
(e.g., token bucket spec) to the nodes along the tunnel? This information 
would be necessary where bandwidth resources are reserved for LSP tunnels 
on the basis of the characteristics of traffic carried on the tunnels.

I think we should convey CoS information through other means, while 
retaining the IntServ SENDER_TSPEC for conveying traffic rate info. There 
are 6 unused bits in the Flags field of the SESSION_ATTRIBUTE. We could use 
three of these bits for conveying CoS information.

Regards,
Arvind.

K. Arvind, Ph.D.
TENOR Networks, Inc.
50, Nagog Park, Acton, MA 01720
W: 978-264-4900 x124
F: 978-264-0671
E: mailto:[email-masked]
U: http://www.tenornetworks.com

-----Original Message-----
From:	Lou Berger [SMTP:[email-masked]]
Sent:	Wednesday, August 25, 1999 10:19 AM
To:	Geping Chen
Cc:	[email-masked]
Subject:	Re: Question on RSVP LSP Tunnel Spec

At 06:07 PM 8/9/99 -0400, Geping Chen wrote:
>I have a question regarding the new FLOWSPEC object for CoS
>service.
>
>Does this mean the SENDER_TSPEC and ADSPEC object also
>need to have a new type of C-Type for CoS service?
>
>Thanks,
>
>Geping

Geping,
	[email-masked] pointed out the omission of the tspec a while back.
Here's what I've asked George to put in on the next rev of the draft:

Old text:

   The format of the Class-of-Service FLOWSPEC object is:

    Class-of-Service FLOWSPEC object: Class = 9, C-Type = 3 (TBA)

New text:

   The same format is used both for SENDER_TSPEC object and
   FLOWSPEC objects.  The formats are:

    Class-of-Service SENDER_TSPEC object: Class = 12, C-Type = 3 (TBA)

    Class-of-Service FLOWSPEC object: Class = 9, C-Type = 3 (TBA)

The is no Adspec associated with Class-of-Service.  Either no Adspec is
included or an int-serv adspec with just the Default General
Characterization Parameters can be used.

Lou

---

From: Lou Berger <[email-masked]>
Date: Thu, 26 Aug 1999 10:52:46 -0400

>on the basis of the characteristics of traffic carried on the tunnels.

Yes.  That is the intent of this object.  It is useful when the CoS values
have local significance to the LSRs along the LSP.  

Think of 802.1p and q, where, like q, this is providing the place to
transport the cos values but does not define what the values mean.

>three of these bits for conveying CoS information.

There are already drafts that cover the case of when you want to signal the
CoS (actually DS/PHS) values that are going to be sent over an LSP that is
setup with an int-serv style allocation.

Lou