Please help with NAT

[Gergo Szakal]

Erik Wikström wrote:
Never used dummynet myself but I seem to recall that ALTQ does not 
provide the same functionality as dummynet. As I understand ALTQ can be 
used to prioritize some packages over others (by using different queues 
and rules that places the packages in the right queue) while dummynet 
supports more advanced stuff like simulating slow/unreliable networks. 
Someone who knows, please correct me if I'm wrong.
There is PRIQ whose purpose is to prioeitize one packet over the other, 
indeed. It makes the system process higher-priority traffic first.
CBQ creates classes in a root queue like this:
root: 100Mbit	- class http 20Mbit (packets going to port 80, 443)
		- class mail 20Mbit (packets going to 110, 25, 995 etc.)
		-class other 60Mbit

Therefore, 20Mbit will be reserved for either mail and http.

HTH