If you are getting redirected to the supplicant provisioning portal you will need to make sure that java is installed and running on the browser since the java applet is what opens the supplicant provisioning portal.
Give that a shot and see if your luck changes, also give the session around 30 seconds to start you should see it come up. (i would recommend mozilla since the plugin option will show up right next to the browser bar.
Table of ContentsIntroductionVersion HistoryPossible Future
UpdatesDocuments PurposeNAT Operation in ASA 8.3+ SectionsRule Types
Network Object NATTwice NAT / Manual NATRule Types used per SectionNAT
Types used with Twice NAT / Manual NAT and Network Obje...
[toc:faq]Introduction:This document describes details on how NAT-T
works.Background:ESP encrypts all critical information, encapsulating
the entire inner TCP/UDP datagram within an ESP header. ESP is an IP
protocol in the same sense that TCP and UDP are I...