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New Member

Mapping ports Please Help! (MIRC help)

Hello, I am living in an house with ethernet. There are 4 3com Superstack II switches connected to one cisco UBR900 router.(basically a proxy setup) I am having trouble uploading while using the program MIRC. To be more specific, I am having trouble initiating DCC chats. I have read some help pages on MIRC on how to resolve this issue, but it involves mapping ports or something to that affect. I have no clue on how to map a port (my best guess is using telenet). Any detailed help would be greatly appreciated. By the way, I do not have the best computer vocabulary and knowledge. Thank you for your time.

New Member

Re: Mapping ports Please Help! (MIRC help)

A lot of college networks block mIRC and similar protocols. You should check with your admin.

Re: Mapping ports Please Help! (MIRC help)


If you're doing NAT on the UBR then you can create a static NAT entry for the ports used by DCC.

Something like the below (I'm not sure what ports DCC uses offhand). You'll have to add multiple entries for multiple ports.

ip nat inside source static tcp 6666 6666

The downside to the above is these ports will be mapped to you're PC only... and if users in your house use stuff on these ports they might not work.

The reason DCC is problematic is because its a direct connection between the 2 users and not going through the IRC server. Sometimes with NAT, if you establish the connection it may work but the other way almost always fails since there isn't a outbound connection to that host.

I use a LinkSys cable/dsl router myself, and use the DMZ host option to forward all traffic to one PC on my network which is my primary PC. This lets me do pretty much everything from this PC.