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so confused about ports!


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Might be good to discuss the basics. A router does exactly that. It routes traffic between two different sets of network addresses. In most cases, there is only one public (WAN for Wide Area Network) address that is supplied by your ISP. Inside that Address there are many ports. Certain ports are used for specific things. Port 80 is for web browsing etc. Another thing most routers do out of the box is something called NAT or Network Address Translation. This is a type of network address masquerading. Simply stated, I can have 5 computers in my house, all on their network (wich is diferent from the ISP side of the router). We won't get into the magic of how the router changes addresses but just know that it does. It keeps the original data there as well so it knows how to get information back to your computer. Now, keeping all that in mind, if Computer A needs to run some special program like uTorrent that requires a specific port, somehow we have to build a map inside our router to tell it that it's okay to allow this one specific port from my Internet/ISP/WAN side of the router to a specific machine. Sooo.. inside your router you need to look for "port forwarding". Somewhere you will answer a few questions like" It's only a single port, not a ragne of ports and I want port 36980 to point to port 36980 on My machine (machine A) and not anyone elses so I'll have to specify an IP address for my machine and the same port. I have an SMC router and it looks like this:

Name: uTorrent

Type: TCP

LAN Server IP: (My machines address and it should be static)

Remote IP: Any (This is to allow anyone access via this port)

Start IP ... Blanked out because I'm not specifying "Any" above

End IP ... ""

Public IP Port: Single Port

Start Public Port: 36980

End Public Port: Blank because I"M using "Single Port" above

Private Ports 36980 (I'm not changing anything so leave public & private the same).

Not sure If this helps or not. Hope it does.

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