srcds need help with ports and ip's

[luxmeister]

i am trying to host a server for gmod10 so some friends can join over the internet. the problem is i can only join through the lan. i have forwarded the the port 27015 tcp,udp to the host computer. sv_lan in the server cfg is set to 0 which i think is correct and to start the server up i enter this into run : "c:\srcds\srcds.exe -console -game garrysmod +map gm_construct -maxplayers 16"
ive looked over many of the other threads and none of them have helped

[luxmeister]

I have also turned on dmz for the host computer but people still cannot join try and join and tell me if you get in ip: 203.213.7.131 port: 27015 also, does windows firewall mess things up if the individual ports are not unblocked? because i dont know how to unblock a range of ports

[luxmeister]

i got it working now... i had forwarded the ports incorrectly and when i turned on dmz it didnt help because the router was still trying to forward the ports. now my brothers home i cant use his computer for a server anyway...