Cisco VPN access over iPhone 4 Personal Hotspot

"- I’m using this VPN method with my iPhone 4 and iPad WiFi (connected through Personal Hotspot on the go) and it works;"

oops seems like it is not impossible:

http://www.macstories.net/tutorials/how-to-set-up-a-vpn-server-on-your-mac-and-a ccess-everything-remotely-with-an-iphone/

I have noted that all vpn or remote desktop solutions will not work over personal hotspot(ph) seems like the iPhone is blocking some ports. First I thought it was the lack of service announces over the network but it seems even with a direct ip connect you can't share vpn connections.

This limits apps like Air display from working over an iPhone and some other services like standard vpn are out of the question as well. There must be a .plist file somewhere in the iPhone 4 version of the 4.3.2 ios that blocks certain ports when on ph. Would be nice to have a look, but I have no expertise in this.

But  +1 Confirm that vpn are locked.

I had a frustrating time of running Cisco VPN on my latop tethered via the iPhone 4 wifi hotspot (same problem - tethered, but when VPN was running, couldn't get to any company network resources), until a network guy traced the network activity, and hit on the solution for me: 

on the Cisco VPN client on the laptop (Win7 64 bit), change the transport option from "IP Sec over UDP" to "IP Sec over TCP".  Now it works fantastic.

Now the question is, what if I am trying to connect to my company's VPN. Teh built-in Mac OS X VPN client does not have the option you describe.

gvorwaller,

I'm guessing there had to be some configuration on the VPN router to allow this.  I tried switching to TCP with the default port and nothing.  Would you happen to have any details?