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Re: wildcard flowid in framework PIB?

Brian, Emmanuel:
We do not need wildcard for the frwkIpFilterFlowId attribute in the
Framework PIB's frwkIpFilterEntry.

The reasoning is as follows:

Please first see
  http://www.ietf.org/internet-drafts/draft-ietf-ipv6-flow-label-03.txt
which I have quote the following from bottom of its section 3:


   The Flow Label value set by the source MUST be delivered unchanged to
   the destination node(s).

   IPv6 nodes MUST NOT assume mathematical or other non-standardized
   properties of the Flow Label values assigned by source nodes. Router
   performance SHOULD NOT be dependent on the distribution of the Flow
   Label values. Especially, the Flow Label bits alone make poor
   material for a hash key.



Rajahalme, et al.         Expires: March 2003                   [Page 3]

INTERNET-DRAFT     draft-ietf-ipv6-flow-label-03.txt      September 2002


   If an IPv6 node is not providing flow-specific treatment, it MUST
   ignore the field when receiving or forwarding a packet.
the draft-ietf-ipv6-flow-label-03.txt draft indicate that there can be 3 conditions
for the Flow Label field of the IPv6 header:
1. It contain the value of zero, meaning it is not used.
2. It contain some specific value, with no defined syntax and semantics.
Hence each value is unique on its own with no relationship to Flow Labels
of containing another value.
3. It contain some value other than zero.

For the first 2 cases indicated above, the filter setup for them is trivial, just
set the frwkIpFilterFlowId to zero or the specific value needed.

For the 3rd case, the filtering definition should use the frwkBaseFilterNegation
set to true and frwkIpFilterFlowId set to zero. This will indicate a filter match
for all Flow Label values other than zero.

Please let me know if this does not resolve the question you have.
Thanks!
-- Kwok --


At 09:13 AM 11/8/02 +1100, Brian Williams wrote:
Hi Emmanuel.
Please see comments inline.
/brian

Emmanuel Dumont wrote:


Hi Brian,

Do you think a wildcard is needed for the FlowId attribute ?
I consider that a wildcard would be needed for FlowId as much as for the other attributes (eg DSCP). I think there would need to be an explanation of why one is not provided.

Which one could you suggest ?

I would think a value of -1 (as used for DSCP) would be appropriate.


Kwok: is it an omission in the FR-PIB ?
Maybe an IPv6 expert can help us to solve that question...

Brian : Do you think that others wildcards are missing ?
This is the only one that I have identified is missing from the filter. I have not done a careful check on anything else in the document.

Emmanuel Dumont
----------------------------
France Telecom OCISI/DIeP (Guyancourt, France)
Mail: em.dumont@wanadoo.fr / emmanuel.dumont@francetelecom.com
----------------------------

-----Message d'origine-----
De : owner-rap@ops.ietf.org [mailto:owner-rap@ops.ietf.org]De la part de
Brian Williams
Envoye : mercredi 6 novembre 2002 00:46
A : rap@ops.ietf.org
Objet : wildcard flowid in framework PIB?

Hi All.
I have a question on the framework PIB. When I look at many of the
filter attributes, there exist values that can be used as wildcards.

The following are a few examples:
- for source and destination addresses, a prefix length of 0 indicates a
match of any address
- for DSCP, a value of -1 will match all DSCP values
- for port numbers, you can set the min and max to include all values
- for protocol number, a value of 255 means match all

However, for the FlowId, the range is specified as 0..1048575 which is
the valid range of the 20 bit label. How is a wildcard FlowId indicated?
/brian