DHCP, a Firewall and a Server

Posted:
in Genius Bar edited January 2014
Hello, I was wondering if anyone knew how to setup Mac OSX w/ a Linksys Router and DHCP Cable modem to run a server. I would like to live MP3 streaming but also keep myself behind the firewall. The Linksys router needs the DCHP turned off so i have manually put the ip information in.

I'm not worried about my ip address changing, I have 145 hour window. i just need to know what numbers to put in

the network settings in OSX and the linksys router so i can still get to the internet.



If i need to do proxy stuff that would alright too.

Thanx.....

Comments

  • Reply 1 of 1
    confusing post but ill try.



    Your cable modem will plug into the internet(WAN) side of your router. Then your computer will plug into the network(LAN) side of the router. Your router will receive, by dhcp, ip information from the cable modem. Usually, if the router is on all the time it will renew its lease before it expires. Which means it will try to keep the same info.



    However, even if this doesnt happen, a dhcp server is usually smart enough that it will try to give the same MAC address the same ip address it had before(to keep things simple for the server it likes to give the same info again and again). So I'd say about 90% of the time or greater you'll have the same ip address for your WAN side.



    The inside part works the same way if you enable DHCP, which you should. So about 90% of the time or greater your computer will have the same ip address for on the LAN side. When you want to do anything on the network that's not on the LAN side your router pushes that info out onto the internet.



    When it does this it substitutes you LAN ip address for the WAN ip address.(this is called NAT, network address translation, although most soho routers also do PAT, port address translation. Basically NAT will just substitute IP addresses, which isnt all that great, but sometimes is, because if more than one person wants to get out on the internet he cant because there's only a total of one WAN ip address. PAT is nice because it will not only substitute IP address but it assigns a port number to each connection. Basically there's alot ~65000 of actual port numbers, some are reserved though so only ~64000 are available for use by PAT. So instead of a connection just having the address of 198.16.1.1 it has the address of 198.16.1.1:2400)



    Now those reserved numbers are common numbers, such as ftp and http. What you need to do is find out what port number the mp3 streaming software you wanna use uses. Make sure your Computer is set to either DHCP(easy way) or you've set it up manually(less easy way) and that you can connect to the internet. Use the network utility.app to get your ip info if you don't know it. And then enter the router config. Just point your browser to <a href="http://192.168.1.1"; target="_blank">http://192.168.1.1</a>;

    and go to the Port Forwarding tab. Enter the port number and your Computers LAN address. You can also go to the DMZ host tab and enter your LAN address, but thats less secure.



    And that should be it. Let us know if it works out for ya. And if you still want to/have to do the static thing(PITA), i can help walk you through that too.
Sign In or Register to comment.