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 From:  Michael <monowall at encambio dot com>
 To:  M0n0wall list <m0n0wall at lists dot m0n0 dot ch>
 Subject:  Traffic shaper TOS and DSCP bits
 Date:  Fri, 16 Apr 2010 12:03:45 +0200
Hello list,

I'm using M0n0wall 1.31 on PC Engines hardware.

Referring to the page '/firewall_shaper_edit.php', there are
several choices for 'IP Type of Service':

  lowdelay
  throughput
  reliability
  mincost
  congestion

It seems that recent RFCs [1] have outdated the classical TOS
semantics used by the most recent M0n0wall release. I'm trying
to match DSCP class selector 5 (CS5) and am confused about the
mapping to the older TOS bits. A document [2] on such mapping
helps a little.

According to my own mapping effort, it seems that none of the
first three TOS choices above correspond to any bits of CS5.
The last two, mincost and congestion, are questionable.

Which of any of the above TOS values should I set to 'yes' on
the traffic shaper pages if I want to filter only CS5 packets?

[1] http://www.ietf.org/rfc/rfc2474
[2] http://www.bogpeople.com/networking/dscp.shtml

Thanks,
Michael