Virtual Identity Server (VIS) is a universal directory solution that provides a single, real-time view of identity data from multiple data stores. The product functions as a virtual directory server that allows applications to connect via LDAP while accessing data from multiple disparate sources without duplicating objects. VIS joins and merges data from various LDAP directories including Active Directory, eDirectory, and Sun directories, as well as SQL databases such as Microsoft SQL Server and Oracle. Applications connect to VIS as they would to any standard LDAP directory, while VIS handles the real-time joining and merging of data from multiple sources. The product operates as an LDAP Proxy Firewall, creating a barrier between client applications and sensitive Active Directory data. It eliminates the need to extend Active Directory schema for third-party applications by storing custom schema and data at the virtual layer. VIS supports multiple join and merge modes including Union Mode for combining objects from all sources, Object Precedence Mode for establishing authoritative directory order, and Attribute Precedence Mode for creating merged views of objects from different directories. The solution provides application-specific views of data, allowing different applications to access different perspectives of the same underlying identity information. Built using Microsoft .NET managed code, VIS integrates with Active Directory and Microsoft infrastructure. It supports LDAP V3 with SSL and non-SSL, RESTful interfaces, PowerShell interfaces, and provides extensibility through .NET programming languages.