This control focuses on communications protection at the session, versus packet, level. The intent of this control is to implement session-level protection where needed (e.g., in service-oriented architectures providing web-based services). NIST Special Publication 800-52 provides guidance on the use of transport layer security (TLS) mechanisms. NIST Special Publication 800-77 provides guidance on the deployment of IPsec virtual private networks (VPNs) and other methods of protecting communications sessions. NIST Special Publication 800-95 provides guidance on secure web services.