In 12.3(14)T Cisco introduced SSL VPN functionality, called WebVPN, on Cisco IOS-based routers. This feature allows you to set up a router to terminate user-based SSL VPNs. Cisco took much of the WebVPN technology that exists in the VPN 3000 concentrators and ported it to the IOS routers. In other words, an IOS-based router, with WebVPN implemented, is by and large a secure web proxy.
The user desktop requirements are essentially the same as those for WebVPN sessions terminating on concentrators:
Supported SSL-enabled browser: Internet Explorer, Netscape, Mozilla, or FireFox
Sun Microsystems Java Runtime (for the Port Forwarding, or thin client, feature only)
Optionally a supported e-mail client: Microsoft Outlook, Netscape Mail, or Eudora ...