Set all outbound traffic to DSCP = 0
Without going in to exhaustive details, the Australian NBN is DiffServ (DSCP if you like) sensitive, so "NBN compliant" routers/modems are required to (re)set DSCP = 0… at least for Telstra services (the largest ISP here in Aus) - see also http://www.telstra.com.au/business-enterprise/download/document/nbn-byo--router-guide.pdf
After reading the pfsense wiki, quite a bit of googling freebsd and pf generally - it seems that setting dscp = 0 should be possible - however i am unable to ascertain how.
In linux, the mangle functions of iptables make this straight forward. A 1:1 equivalent function doesnt seem to exist in BSD (please prove me wrong)
Can someone suggest how to ensure all outbound traffic on an interface is set DSCP.0... also NBN just drops traffic that exceeds your Mbit/s upload limit so shaping is needed anyway - so applying both in one hit would be nice.
Unfortunately that is not possible in pfSense. We can only match, not set, DSCP at this time.
perhaps the very old ng_mangle could be resuscitated ?
Couldn't you coerce an outside switch between the WAN port and the modem to do that?
Curiously, pfsense can do rather basic marking of 802.1p (layer2) - but not diffserv in layer 3.