What SP describes Secure Portal VPNs and Secure Tunnel VPN?

• A. 800-113 Guide to SSL VPN
• B. 800-81 Secure DNS Deployment Guide
• C. 800-53 Rev 4
• D. 800-61 Incident Handling Guide

Answer: (A)

Secure Portal VPNs and Secure Tunnel VPNs are described in a publication that focuses on SSL-based remote access methods. NIST Special Publication 800-113, Guide to SSL VPN, explains how SSL VPNs operate and distinguishes the two common deployment modes: Secure Portal VPN, which provides access through a web-style portal to a defined set of resources, and Secure Tunnel VPN, which establishes an SSL/TLS tunnel granting broader network access. The other options cover different topics—DNS deployment, security controls, and incident handling—so they don’t describe SSL VPN approaches. Therefore, the SP that describes Secure Portal VPNs and Secure Tunnel VPN is NIST SP 800-113, Guide to SSL VPN.