Check with Apple on this one. Since Jetpacks do not come with a an Ethernet cable port you would need the AirPort to complete what is know as a "wireless bridge" connection. If the AirPort can function in this way then the two can be used together. As far as the Jetpack is concerned in this scenario the AirPort is just another wireless device, no extra configuration necessary.
Without a wireless bridge mode (where the AirPort connects wirelessly to the Jetpack) you would need a 3rd device to convert the WiFi signal from the Jetpack into an Ethernet cabled connection.
I own apple routers. (base station, express and extreme) They require a wired Ethernet connection to a modem. Some mifi devices do have Ethernet ports. Without one NO and Apple router will not work.
AGERMAN, we know how important it is to stay connected with all of your various equipment. The 6620L jetpack supports Type A USB tethering and Wi-Fi. I understand that you're looking to connect this device with an Apple Airport Extreme. I would recommend speaking with Apple to see if it will be able to connect with either of these two options the jetpack offers. There is not an ethernet port on this model.
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