RouterOS cannot do what packetfence does. PacketFence is a NAC (Network Access Control) Platform. It is second to none, and is superior to OPENNAC.
All RouterOS needs to do to support it is add the dynamic VLAN Assignment… See this post http://forum.mikrotik.com/t/add-dynamic-vlan-assignment/76436/1
Someone Decreased my Karma for posting, but I thought it was a valid post. Sorry for offending whoever it was.. I only give out karma… But I Never try to lower other’s karma…