Internet Authentication Service
Encyclopedia
Internet Authentication Service (IAS) is a component of Windows Server
operating systems that provides centralized user authentication, authorization and accounting
.
(RRAS) security is sufficient for small networks, larger companies often need a dedicated infrastructure for authentication. RADIUS
is a standard for dedicated authentication servers.
Windows 2000 Server and Windows Server 2003
include the Internet Authentication Service (IAS), an implementation of RADIUS server. IAS supports authentication for Windows-based clients, as well as for third-party clients that adhere to the RADIUS standard. IAS stores its authentication information in Active Directory
, and can be managed with Remote Access Policies. IAS first showed up for Windows NT 4.0
in the Windows NT 4.0 Option Pack and in Microsoft Commercial Internet System (MCIS) 2.0 and 2.5.
While IAS requires the use of an additional server component, it provides a number of advantages over the standard methods of RRAS authentication. These advantages include centralized authentication for users, auditing and accounting features, scalability, and seamless integration with the existing features of RRAS.
In Windows Server 2008, Network Policy Server (NPS) replaces the Internet Authentication Service (IAS). NPS performs all of the functions of IAS in Windows Server 2003 for VPN and 802.1X-based wireless and wired connections and performs health evaluation and the granting of either unlimited or limited access for Network Access Protection
clients.
as well (or in place of).
When logging to SQL, IAS appears to wrap the data into XML
, then calls the stored procedure report_event, passing the XML data as text... the stored procedure can then unwrap the XML and save data as desired by the user.
Option Pack.
Windows 2000 Server's implementation added support for more intelligent resolution of user names that are part of a Windows Server domain
, support for UTF-8
logging, and improved security. It also added support for EAP Authentication for IEEE 802.1x
networks. Later on it added PEAP (with service Pack 4).
Windows Server 2003's implementation introduces support for logging to a Microsoft SQL Server
database, cross-forest authentication (for Active Directory user accounts in other Forests that the IAS server's Forest has a cross-forest trust relationship with, not to be confused with Domain trust which has been a feature in IAS since NT4), support for IEEE 802.1X
port-based authentication, and other features.
All versions of IAS support multi domain setups. Only Windows Server 2003 supports cross forest. While NT4 version includes a Radius Proxy, Windows 2000 didn't have such a feature. Windows Server 2003 reintroduced the feature and is capable of intelligently proxy, load balance, and tolerate faults from faulty or unreachable back-end servers.
Windows Server
Windows Server is a brand name for a group of server operating systems released by Microsoft Corporation. All are part of Microsoft Servers.- Members :This brand includes the following software:* Windows 2000 Server* Windows Server 2003...
operating systems that provides centralized user authentication, authorization and accounting
AAA protocol
In computer security, AAA commonly stands for authentication, authorization and accounting.- Authentication :Authentication refers to the process where an entity's identity is authenticated, typically by providing evidence that it holds a specific digital identity such as an identifier and the...
.
Overview
While Routing and Remote Access ServiceRouting and Remote Access Service
Routing and Remote Access Service is a Microsoft API and server software make it possible to create applications to administer the routing and remote access service capabilities of the operating system, to function as a network router, and developers can also use RRAS to implement routing protocols...
(RRAS) security is sufficient for small networks, larger companies often need a dedicated infrastructure for authentication. RADIUS
RADIUS
Remote Authentication Dial In User Service is a networking protocol that provides centralized Authentication, Authorization, and Accounting management for computers to connect and use a network service...
is a standard for dedicated authentication servers.
Windows 2000 Server and Windows Server 2003
Windows Server 2003
Windows Server 2003 is a server operating system produced by Microsoft, introduced on 24 April 2003. An updated version, Windows Server 2003 R2, was released to manufacturing on 6 December 2005...
include the Internet Authentication Service (IAS), an implementation of RADIUS server. IAS supports authentication for Windows-based clients, as well as for third-party clients that adhere to the RADIUS standard. IAS stores its authentication information in Active Directory
Active Directory
Active Directory is a directory service created by Microsoft for Windows domain networks. It is included in most Windows Server operating systems. Server computers on which Active Directory is running are called domain controllers....
, and can be managed with Remote Access Policies. IAS first showed up for Windows NT 4.0
Windows NT 4.0
Windows NT 4.0 is a preemptive, graphical and business-oriented operating system designed to work with either uniprocessor or symmetric multi-processor computers. It was the next release of Microsoft's Windows NT line of operating systems and was released to manufacturing on 31 July 1996...
in the Windows NT 4.0 Option Pack and in Microsoft Commercial Internet System (MCIS) 2.0 and 2.5.
While IAS requires the use of an additional server component, it provides a number of advantages over the standard methods of RRAS authentication. These advantages include centralized authentication for users, auditing and accounting features, scalability, and seamless integration with the existing features of RRAS.
In Windows Server 2008, Network Policy Server (NPS) replaces the Internet Authentication Service (IAS). NPS performs all of the functions of IAS in Windows Server 2003 for VPN and 802.1X-based wireless and wired connections and performs health evaluation and the granting of either unlimited or limited access for Network Access Protection
Network Access Protection
Network Access Protection is a Microsoft technology for controlling network access of a computer host based on the system health of the host, first introduced in Windows Server 2008....
clients.
Logging
By default, IAS logs to local files (%systemroot%\LogFiles\IAS\*) though it can be configured to log to SQLSQL
SQL is a programming language designed for managing data in relational database management systems ....
as well (or in place of).
When logging to SQL, IAS appears to wrap the data into XML
Extensible Markup Language
Extensible Markup Language is a set of rules for encoding documents in machine-readable form. It is defined in the XML 1.0 Specification produced by the W3C, and several other related specifications, all gratis open standards....
, then calls the stored procedure report_event, passing the XML data as text... the stored procedure can then unwrap the XML and save data as desired by the user.
History
The initial version of Internet Authentication Service was included with the Windows NT 4.0Windows NT 4.0
Windows NT 4.0 is a preemptive, graphical and business-oriented operating system designed to work with either uniprocessor or symmetric multi-processor computers. It was the next release of Microsoft's Windows NT line of operating systems and was released to manufacturing on 31 July 1996...
Option Pack.
Windows 2000 Server's implementation added support for more intelligent resolution of user names that are part of a Windows Server domain
Windows Server domain
A Windows domain is a collection of security principals that share a central directory database. This central database contains the user accounts and security information for...
, support for UTF-8
UTF-8
UTF-8 is a multibyte character encoding for Unicode. Like UTF-16 and UTF-32, UTF-8 can represent every character in the Unicode character set. Unlike them, it is backward-compatible with ASCII and avoids the complications of endianness and byte order marks...
logging, and improved security. It also added support for EAP Authentication for IEEE 802.1x
IEEE 802.1X
IEEE 802.1X is an IEEE Standard for port-based Network Access Control . It is part of the IEEE 802.1 group of networking protocols. It provides an authentication mechanism to devices wishing to attach to a LAN or WLAN....
networks. Later on it added PEAP (with service Pack 4).
Windows Server 2003's implementation introduces support for logging to a Microsoft SQL Server
Microsoft SQL Server
Microsoft SQL Server is a relational database server, developed by Microsoft: It is a software product whose primary function is to store and retrieve data as requested by other software applications, be it those on the same computer or those running on another computer across a network...
database, cross-forest authentication (for Active Directory user accounts in other Forests that the IAS server's Forest has a cross-forest trust relationship with, not to be confused with Domain trust which has been a feature in IAS since NT4), support for IEEE 802.1X
IEEE 802.1X
IEEE 802.1X is an IEEE Standard for port-based Network Access Control . It is part of the IEEE 802.1 group of networking protocols. It provides an authentication mechanism to devices wishing to attach to a LAN or WLAN....
port-based authentication, and other features.
All versions of IAS support multi domain setups. Only Windows Server 2003 supports cross forest. While NT4 version includes a Radius Proxy, Windows 2000 didn't have such a feature. Windows Server 2003 reintroduced the feature and is capable of intelligently proxy, load balance, and tolerate faults from faulty or unreachable back-end servers.
External links
- Internet Authentication Service on Microsoft TechNet
- Deploying Internet Authentication Service (IAS) in Windows 2003
- Internet Authentication Service in the Microsoft Windows 2000 Resource Kit
- Article describing how to log IAS (RADIUS) + DHCP to SQL
- Configure IAS RADIUS for secure 802.1x wireless LAN
- How to self-sign a RADIUS server for secure PEAP or EAP-TTLS authentication
- IAS Log parsing utility. Allows to visualize ias log files