So Apple this morning released beta one of iOS 4.3, bringing with it a whole heap of little tweaks and a couple of major features, including the new ‘Personal Hotspot’ feature.
Personal Hotspot extends on the existing tethering support in iOS by adding WiFi as a sharing method in addition to the existing Bluetooth and USB methods.
As far as I can tell, I’d believe it’s tied to the tethering settings; if you carrier has tethering enabled (and depending on your carrier, you’ve paid for access), you should have access to WiFi tethering; it’s just another method in addition to bluetooth and USB tethering. However, don’t quote me on this!
More interesting as far as I’m concerned, the main difference between this built in WiFi tethering and earlier jailbreak methods (MyWi, etc) is that the native tethering uses ‘Infrastructure’ mode for broadcasting as opposed to Ad-Hoc (which is what MyWi uses). Infrastructure mode is compatible with more devices (for example, Windows Phone 7 and the Sony PlayStation 3 don’t support Ad-Hoc networks).
According to Wikipedia;
The 802.11 has two basic modes of operation: Ad hoc mode enables peer-to-peer transmission between mobile units. Infrastructure mode in which mobile units communicate through an access point that serves as a bridge to a wired network infrastructure is the more common wireless LAN application the one being covered.
As you can see in the following screenshot, the MyWi network (running on my iPad rocking iOS 4.2.1) shows up under ‘Devices’ whereas my iPhone appears as a standard network.