PortalGuard is a software solution that provides five layers of authentication functionality including two-factor authentication. It can enforce two-factor authentication for accessing cloud applications directly, via VPN using RADIUS, or during self-service password resets. PortalGuard delivers one-time passwords (OTPs) for verification via SMS, email, voice call, printer, or transparent tokens. It has configurable OTP settings and supports standard RADIUS authentication for VPN access. Implementation requires server-side software installation on IIS servers and optional client-side software for additional features.