Setting Up Mixed mode (NAT/NAPT)

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So you have 5 IP's from your ISP but have to connect 6 or more PC's?
No problem, as the EN5861 will do both no-NAT and NAT simultaneously, and simply!!

The first thing to do is set the router up for NAT operation, when this is done you can connect as normal to your ISP and you will be given the same WAN IP for your router. Any machines on your network which obtain their IP via DHCP from the router will appear to have this IP on the WAN side.

The command to use on the router is sys addhostmapping and is in the form of:-

sys addhostmapping <first LAN IP> <last LAN IP> <first public IP>

This assumes you were assigned 98.76.54.1 to 98.76.54.4 for your useable IP's and you are using the default 192.168.254.x LAN subnet on the router.

You can verify the mapping by sys list.

The reason to use such high LAN IP's is that it's above the default DHCP pool so there shouldn't be any conflicts, this will allow all the PC's on the LAN to connect to each other.
Another possibility would be to use a different subnet altogether which would in effect create a partial DMZ for these PC's (a full DMZ would require some firewall filters on the ethernet interface).

Now set your PC's with one of the 5 public IP's you were given by your ISP.

Remember to set your router as the gateway and to set some DNS server IP's (these could also be set as the routers IP). The WAN IP of this PC will now be 98.76.54.1

Now you will have 5 no-NAT public IP's, but those which connect using DHCP will be NAT'ed.