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When I plug in two wired NICs to the computer, I can get two IP addresses on the same network. Is such a setup possible with one wired ethernet card and one wireless card?

If so, how?

If not, is there a good reason for not having that capability? (and why?)

Update: To explain the reason to have that capability, here is the scenario I'm dealing with:

1) I have a web server which needs to use 2 IP addresses so it can use 2 different SSL certificates for different domains. This wouldn't be a problem if the server wasn't sitting behind a 2wire router via AT&T, which, from what I can tell, imposes a limit of one IP address per MAC address. (not that it imposes it specifically, but that I could find no information on how to get it to work otherwise, and while I got it close to working, there were lots of strange errors occurring, which have gone away now that I've moved closer to how they strongly encourage you to set it up).

Update 2:

I see some downvotes, and I'd be happy to improve this question if someone could give me pointers on things they'd like to see included. I apologize for the bad question, but please let me know how I can improve it.

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I think the question should be, "is there to a good reason to have that capability?" – gravyface Mar 15 '12 at 23:58
Given it's possible with 2 wired cards, I'm wondering why not allow wireless + wired with the same functionality. – Sammy Larbi Mar 16 '12 at 0:51

You can use IP aliases under a single interface without issue in IIS and Windows 2008. Under the adapter properties, define a second IP under (I think) the Alternative IP Addresses tab; it's in there somewhere, don't have Windows handy at the moment.

You can then bind the second IP address under a second Web Site in IIS and choose the certificate accordingly.

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I tried doing that. As soon as I hit "OK" to accept the changes, the computer rebooted and went into checkdisk mode and I lost an hour of work. I'm not sure if it was connected, but it seemed like it enough such that I'd not want to try again. I've successfully done it in the past like that w/ different subnets, and this doesn't get around the "one IP per MAC" that I suspect, but if after reading this you still think it's worth a shot, I'm willing to try it again. (assuming I read it before I've figured out an alternative). Let me know. – Sammy Larbi Mar 16 '12 at 0:58
Something else must be wrong for that to happen. I have a production webserver (2008 R2) with 10 IPs on it, all on the same subnet, no issues. – gravyface Mar 16 '12 at 1:28
Unfortunately, I think the "something wrong" is the way the 2wire router will only route one public IP to one MAC .. so it will only recognize one of the IPs set in the settings. If I can, I'll try it out again tomorrow after I have our workaround "fix" in place. In fact, the web server had several local IPs on the same network in the same card before moving to this 2wire, and only now it is acting haywire. – Sammy Larbi Mar 16 '12 at 5:25

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