SphereShield for Skype for Business is a security solution designed to protect Microsoft Skype for Business (Lync) environments from unauthorized access and credential-based attacks when users connect from external or unmanaged networks. Core security capabilities include: - Two-factor authentication (TFA) using device identification as a second factor alongside username and password, eliminating the need to store Active Directory credentials on mobile devices - Device access control with three enrollment options: automatic registration, managed device (MDM) conditional registration, and self-service portal enrollment - MDM conditional access that continuously verifies device compliance status and automatically blocks access for devices that fall out of compliance or are remotely wiped - Application firewall that sanitizes and validates anonymous traffic in the DMZ before it reaches internal servers - Proxy-side brute force and denial-of-service attack prevention - Account lockout protection to prevent AD lockouts caused by stale credentials on mobile devices - Smart card authentication support by generating dedicated Skype for Business credentials, removing the need to store AD credentials on devices The product supports deployment on Microsoft Proxy (TMG/ISA) and via a dedicated reverse proxy called Bastion. It includes a self-service access portal, multi-LDAP support, multi-level admin management, IP range-based access restrictions, and reporting capabilities covering authentication, devices, security auditing, and failed login events. Additional features include disclaimer display for internal and external users, eDiscovery support, and Wi-Fi, VPN, and app-based MDM registration methods.