[jeff k]

I just got Mountain Lion, and this new feature, I'm curious:

Mac help says,
"Back to My Mac requires a router that supports NAT Port Mapping Protocol (NAT-PMP) or Universal Plug and Play (UPnP) to share services."

Realistically, at most hotels/ motels (the scenario where I could maybe want to get to my desktop hardrive and files), is this going to work?

[abbaZaba]

That is referring to the router your Mac AT HOME is connected to, not whatever you come across in your travels. Back To My Mac is for connecting to the Mac you leave on at home. You use a 2nd Mac, usually a laptop but can be any device that supports Back To My Mac, to connect to the one at home and access its files.

[jeff k]

Thanks Abba for clarifying that.
So how do I know if my Router is ready to roll at Home for this. I have an Apple extreme for my home router so you would think I'm good to go, or not?

[mduell]

Depends which version of the Airport Extreme and which firmware. Check the router config to see if you have the NATPMP option and it's enabled.

[James Katt]

Generally, Apple's routers are compatible with Back-to-My-Mac.

[jeff k]

thanks M,
I looked in the airport software (is this correct), I clicked on various tabs and did not see NATPMP.
Where precisely should I look? thanks.

[mduell]

The first hit on google for "apple airport natpmp" is http://support.apple.com/kb/HT1833

Enabling the NAT Port Mapping Protocol

In the Finder, choose Utilities from the Go menu.
Open Airport Admin Utility.
In the resulting Select Base Station window, select your Airport Extreme or AirPort Express from the list.
Click Configure, then enter the base station password when prompted.
Click the Base Station Options button.
Select the Enable NAT Port Mapping Protocol checkbox.
Click OK.
Click the Update button and wait for the base station to restart.

After your Airport Extreme or AirPort Express restarts, NAT-PMP will be enabled.