The RB493 has nine ethernet ports and three miniPCI slots, it also has a switch chip, so the ethernet ports 2-9 can be grouped together to make it act as a switch.
RB493 includes RouterOS - the operating system, which will turn this powerful system into a highly sophisticated router, firewall or bandwidth manager.
The RB493AH model includes the higher speed Atheros 680MHz CPU, more memory, and a Level5 license for more simultaneous tunnel interfaces and hotspot users.