Now that I've had the opportuninty to host a few games for community members I have been able to de-generalize (is that even a word? hehe) some of my networking information.
Here is all pertinent network-config related information for SINS as I see it.
1. I have seen no evidence that
both TCP and UDP port 6112 need to be forwarded to your PC's IP address. All of my testing indicates that
forwarding TCP port 6112 to your PC's IP is sufficient.2. I have also seen TCP port 6000 "listening" for traffic on my host (I'm assuming this is the connection to IronClad Online) so it wouldn't hurt to forward that port to your PC's IP as well.
3. MAKE SURE that any/all security software (that means all firewalls, anti-virus, anti-spam, privacy-protection, internet-monitors, etc.) is set with the proper "exceptions" for SINS or if you don't know how to do that properly then disable it completely. I speak from experience when I say that as long as you're behind a router and
not in the DMZ your security software is actually only protecting you from yourself.

**Important** Anyone currently a high-speed internet subscriber and
not behind a router is doing themselves and their computer system as huge diservice period.
If I told you that I was going to leave all of my windows and doors unlocked and wide open but that I'd have my burglar alarm on (so I'm safe) and would vacuum the house everyday to clean up the daily dust & debris you'd look at me like I'm crazy! Well....that's how I look at anyone who doesn't see the need for a router....
4. I can absolutely confirm that the Windows Firewall is in no way blocking SINS. I have hosted ALL of the games that I've hosted from behind a properly configured and running Windows Firewall.
To re-cap:Ports that need forwarding for SINS (client&host):
TCP 6112 < --- port the game.exe listens on
TCP 6000 < --- port I'm assuming IronClad Online uses
the above ports will need to be forwarded through any network device hardware (router) you have between your computer and the internet as well as allowed connection through any software firewall along the same path.
Having said all of the above. There is still the issue of NAT. What I mean by that is. How "seriously" your router/firewall takes NAT (its job). The best (most pc-user-friendly) explanation I can give on NAT-filtering etc. I've already presented in my first post in this thread as well as in the "easy-to-read" guide linked from this thread. Should anyone however have any more in-depth questions I'll be glad to invite you onto my TeamSpeak server so I can talk you through your issues. For the TS server information please contact my via xfire (the1monk).Thank you,
now I'm off to bed..

the Monk