Port Requirements for the Microsoft Windows Server System.

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SUMMARY

This article discusses the network ports and protocols that are used by server products and their subcomponents in the Microsoft Windows server system.

The Windows server system includes a comprehensive and integrated infrastructure that is designed to meet the requirements of developers and of information technology (IT) professionals . This system is designed to run programs and solutions that information workers can use to obtain, to analyze, and to share information quickly and easily . These Microsoft server products use a variety of network ports and protocols to communicate with client systems and with other server systems over the network . Dedicated firewalls, host-based firewalls, and Internet Protocol security (IPSec) filters are other important components that are required to help secure your network . However, if these technologies are configured to block ports and protocols that are used by a specific server, that server will no longer respond to client requests.

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Overview

The following list provides an overview of the information that this article contains:

This article uses certain terms in specific ways. To help avoid confusion, make sure that you understand how this document uses these terms. The following list describes these terms:

This article does not specify which services rely on other services for network communication . For example, many services rely on the remote procedure call (RPC) or DCOM features in Microsoft Windows to assign them dynamic TCP ports . The Remote Procedure Call service coordinates requests by other system services that use RPC or DCOM to communicate with client computers . Many other services rely on network basic input/output system (NetBIOS) or SMBs, protocols that are actually provided by the Server service . Others rely on HTTP or on Hypertext Transfer Protocol Secure (HTTPS) . These protocols are provided by Internet Information Services (IIS) . A full discussion of the architecture of the Windows operating systems is beyond the scope of this article . However, detailed documentation on this subject is available on Microsoft TechNet and on the Microsoft Developer Network (MSDN) . While many services may rely on a particular TCP or UDP port, only a single service or process can be actively listening on that port at any one time.

When you use RPC with TCP/IP or with UDP/IP as the transport, inbound ports are frequently dynamically assigned to system services as required; TCP/IP and UDP/IP ports that are higher than port 1024 are used . These are frequently informally referred to as "random RPC ports." In these cases, RPC clients rely on the RPC endpoint mapper to tell them which dynamic port(s) were assigned to the server . For some RPC-based services, you can configure a specific port instead of letting RPC assign one dynamically . You can also restrict the range of ports that RPC dynamically assigns to a small range, regardless of the service . For more information about this topic, see the " References " section of this article.

This article includes information about the system services roles and the server roles for the Microsoft products that are listed in the "Applies to " section at the end of this article. While this information may also apply to Microsoft Windows XP and to Microsoft Windows 2000 Professional, this article is intended to focus on server-class operating systems. Because of this, this article describes the ports that a service listens on instead of the ports that client programs use to connect to a remote system.

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System Services Ports

This section provides a description of each system service, includes the logical name that corresponds to the system service, and displays the ports and the protocols that each service requires.

Application Layer Gateway Service

This subcomponent of the Internet Connection Sharing (ICS)/Internet Connection Firewall (ICF) service provides support for plug-ins that allow network protocols to pass through the firewall and work behind Internet Connection Sharing . Application Layer Gateway (ALG) plug-ins can open ports and change data (such as ports and IP addresses) that are embedded in packets . File Transfer Protocol (FTP) is the only network protocol with a plug-in that is included with Windows Server 2003, Standard Edition, and Windows Server 2003, Enterprise Edition. The ALG FTP plug–in is designed to support active FTP sessions through the network address translation (NAT) engine that these components use . The ALG FTP plug–in supports these sessions by redirecting all traffic that passes through the NAT and that is destined for port 21 to a private listening port in the range of 3000 to 5000 on the loopback adapter . The ALG FTP plug–in then monitors and updates FTP control channel traffic so that the FTP plug-in can forward port mappings through the NAT for the FTP data channels . The FTP plug–in also updates ports in the FTP control channel stream.

System service name: ALG

ASP.NET State Service

ASP.NET State Service provides support for ASP.NET out-of-process session states. ASP.NET State Service stores session data out-of-process. The service uses sockets to communicate with ASP.NET that is running on a Web server.

System service name: aspnet_state

Certificate Services

Certificate Services is part of the core operating system . By using Certificate Services, a business can act as its own certification authority (CA) . In this way, the business can issue and manage digital certificates for programs and protocols such as Secure/Multipurpose Internet Mail Extensions (S/MIME), Secure Sockets Layer (SSL), Encrypting File System (EFS), IPSec, and smart card logon . Certificate Services relies on RPC and on DCOM to communicate with clients by using random TCP ports that are higher than port 1024.

System service name: CertSvc

Cluster Service

The Cluster service controls server cluster operations and manages the cluster database. A cluster is a collection of independent computers that act as a single computer. Managers, programmers, and users see the cluster as a single system. The software distributes data among the nodes of the cluster. If a node fails, other nodes provide the services and data that was formerly provided by the missing node. When a node is added or repaired, the cluster software migrates some data to that node.

System service name: ClusSvc

Computer Browser

The Computer Browser system service maintains an up-to-date list of computers on your network and supplies the list to programs that request it. The Computer Browser service is used by Windows-based computers to view network domains and resources. Computers that are designated as browsers maintain browse lists that contain all shared resources that are used on the network. Earlier versions of Windows programs, such as My Network Places, the net view command, and Windows Explorer, all require browsing capability. For example, when you open My Network Places on a computer that is running Microsoft Windows 95, a list of domains and computers appears. To display this list, the computer obtains a copy of the browse list from a computer that is designated as a browser.

System service name: Browser

DHCP Server

The DHCP Server service uses the Dynamic Host Configuration Protocol (DHCP) to automatically allocate IP addresses. By using this service, you can adjust the advanced network settings of DHCP clients. For example, you can configure network settings such as Domain Name System (DNS) servers and Windows Internet Name Service (WINS) servers. You can establish one or more DHCP servers to maintain TCP/IP configuration information and to provide that information to client computers.

System service name: DHCPServer

Distributed File System

The Distributed File System (DFS) service manages logical volumes that are distributed across a local area network (LAN) or wide area network (WAN) and is required for the Microsoft Active Directory directory service SYSVOL share. DFS is a distributed service that integrates disparate file shares into a single logical namespace.

System service name: Dfs

Distributed Link Tracking Server

The Distributed Link Tracking Server system service stores information so that files that are moved between volumes can be tracked to each volume in the domain. The Distributed Link Tracking Server service runs on each domain controller in a domain. This service enables the Distributed Link Tracking Client service to track linked documents that have been moved to a location in another NTFS file system volume in the same domain.

System service name: TrkSvr

Distributed Transaction Coordinator

The Distributed Transaction Coordinator (DTC) system service is responsible for coordinating transactions that are distributed across multiple computer systems and resource managers, such as databases, message queues, file systems, or other transaction-protected resource managers . The DTC system service is required if transactional components are configured through COM+ . It is also required for transactional queues in Message Queuing (also known as MSMQ) and SQL Server operations that span multiple systems.

System service name: MSDTC

DNS Server

The DNS Server service enables DNS name resolution by answering queries and update requests for DNS names. DNS servers are required to locate devices and services that are identified by using DNS names and to locate domain controllers in Active Directory.

System service name: DNS

Event Log

The Event Log system service logs event messages that are generated by programs and by the Windows operating system . Event Log reports contain information that can be useful in diagnosing problems . Reports are viewed in Event Viewer . The Event Log service writes events that are sent by programs, by services, and by the operating system to log files . The events contain diagnostic information in addition to errors that are specific to the source program, the service, or the component . The logs can be viewed programmatically through the event log APIs or through the Event Viewer in an MMC snap-in.

System service name: Eventlog

Exchange Server

Microsoft Exchange Server includes several system services . When a MAPI client, such as Microsoft Outlook, connects to an Exchange server, the client first connects to the RPC endpoint mapper (the RPC Locator Service) on TCP port 135 . The RPC endpoint mapper tells the client what ports to use to connect to the Exchange Server service . These ports are dynamically assigned . Microsoft Exchange Server 5.5 uses two ports: one for the information store and one for the directory . Microsoft Exchange 2000 Server and Microsoft Exchange Server 2003 use three ports: one for the information store and two for the system attendant . You can also use Microsoft Office Outlook 2003 to connect to servers that are running Exchange Server 2003 by using RPC over HTTP . Exchange Server can also provide support for other protocols, such as SMTP, Post Office Protocol 3 (POP3), and IMAP.

Fax Service

Fax Service, a Telephony API (TAPI)–compliant system service, provides fax capabilities. By using Fax Service, users can send and receive faxes from their desktop programs by using either a local fax device or a shared network fax device.

System service name: Fax

File Replication

The File Replication service (FRS) allows files to be automatically copied and maintained on many servers at the same time. FRS is the automatic file replication service in Windows 2000 and in Windows Server 2003. Its function is to replicate the SYSVOL share to all domain controllers. Additionally, you can configure FRS to replicate files among alternate targets that are associated with the fault-tolerant DFS.

System service name: NtFrs

File Server for Macintosh

By using the File Server for Macintosh system service, Macintosh computer users can store and access files on a computer that is running Windows Server 2003. If this service is turned off or blocked, Macintosh clients cannot access or store files on that computer.

System service name: MacFile

FTP Publishing Service

FTP Publishing Service provides FTP connectivity . By default, the FTP control port is 21 . However, you can configure this system service through the Internet Information Services (IIS) Manager snap-in . The default data (that is used for active mode FTP) port is automatically set to one port less than the control port . Therefore, if you configure the control port to port 4131, the default data port is port 4130 . Most FTP clients use passive mode FTP . This means that the client initially connects to the FTP server by using the control port, the FTP server assigns a high TCP port between ports 1025 and 5000, and then the client opens a second connection to the FTP server for transferring data . You can configure the range of high ports by using the IIS metabase.

System service name: MSFTPSVC

HTTP SSL

The HTTP SSL system service enables IIS to perform SSL functions . SSL is an open standard for establishing an encrypted communications channel to help prevent the interception of critical information, such as credit card numbers . Although this service is designed to work on other Internet services, it is primarily used to enable encrypted electronic financial transactions on the World Wide Web (WWW) . You can configure the ports for this service through the Internet Information Services (IIS) Manager snap-in.

System service name: HTTPFilter

Internet Authentication Service

Internet Authentication Service (IAS) performs centralized authentication, authorization, auditing, and accounting of users who are connecting to a network. These users can be on a LAN connection or on a remote connection. IAS implements the Internet Engineering Task Force (IETF) standard Remote Authentication Dial-In User Service (RADIUS) protocol.

System service name: IAS

Internet Connection Firewall (ICF)/Internet Connection Sharing (ICS)

This system service provides NAT, addressing, and name resolution services for all computers on your home network or your small-office network . When the Internet Connection Sharing feature is enabled, your computer becomes an "Internet gateway" on the network, and other client computers can then share one connection to the Internet, such as a dial-up connection or a broadband connection . This service provides basic DHCP and DNS services but will work with the full-featured Windows DHCP or DNS services. When ICF and Internet Connection Sharing act as a gateway for the rest of the computers on your network, they provide DHCP and DNS services to the private network on the internal network interface. They do not provide these services on the external-facing interface.

System service name: SharedAccess

Kerberos Key Distribution Center

When you use the Kerberos Key Distribution Center (KDC) system service, users can log on to the network by using the Kerberos version 5 authentication protocol. As in other implementations of the Kerberos protocol, the KDC is a single process that provides two services: the Authentication Service and the Ticket-Granting Service. The Authentication Service issues ticket granting tickets, and the Ticket-Granting Service issues tickets for connection to computers in its own domain.

System service name: kdc

License Logging

The License Logging system service is a tool that was originally designed to help customers manage licenses for Microsoft server products that are licensed in the Server Client Access License (CAL) model . License Logging was introduced with Microsoft Windows NT Server 3.51 . By default, the License Logging service is disabled in Windows Server 2003 . Because of original design constraints and evolving license terms and conditions, License Logging may not provide an accurate view of the total number of CALs that are purchased compared to the total number of CALs that are used on a particular server or across the enterprise . The CALs that are reported by License Logging may conflict with the interpretation of the End-User License Agreement (EULA) and with Product Use Rights (PUR) . License Logging will not be included in future versions of the Windows operating system . Microsoft recommends that only users of the Microsoft Small Business Server family of operating systems enable this service on their servers.

System service name: LicenseService

Local Security Authority

The Local Security Authority (LSASS) service provides core operating system security mechanisms. The service uses random TCP ports that are assigned through the RPC service for domain controller replication. Although LSASS can use all the following protocols, it may use only a subset of them. For example, if you configure a VPN gateway that lies behind a filtering router, you might use Layer 2 Tunneling Protocol (L2TP) together with IPSec. In this scenario, you must allow IPSec Encapsulating Security Protocol (ESP) (IP protocol 50), IPSec Network Address Translator Traversal NAT-T (UDP port 4500), and IPSec Internet Security Association and Key Management Protocol (ISAKMP) (UDP port 500) through the router.

NotePacket filters for L2TP traffic are not required, because L2TP is protected by IPSec ESP.

System service name: LSASS

Message Queuing

The Message Queuing system service is a messaging infrastructure and development tool for creating distributed messaging programs for Windows. These programs can communicate across heterogeneous networks and can send messages between computers that may be temporarily unable to connect to each other. Message Queuing helps provide security, efficient routing, support for sending messages within transactions, priority-based messaging, and guaranteed message delivery.

System service name: MSMQ

Messenger

The Messenger system service sends messages to or receives messages from users and computers, administrators, and the Alerter service. This service is not related to Windows Messenger. If you disable the Messenger service, notifications that are sent to computers or users who are currently logged on the network are not received. Additionally, the net send command and the net name command no longer function.

System service name: Messenger

Microsoft Exchange MTA Stacks

In Microsoft Exchange 2000 Server and Microsoft Exchange Server 2003, the Message Transfer Agent (MTA) is frequently used to provide backward-compatible message transfer services between Exchange 2000 Server-based servers and Exchange Server 5.5-based servers in a mixed-mode environment.

System service name: MSExchangeMTA

Microsoft Operations Manager 2000

Microsoft Operations Manager (MOM) 2000 delivers enterprise-class operations management by providing comprehensive event management, proactive monitoring and alerting, reporting, and trend analysis . After you install MOM 2000 Service Pack 1 (SP1), MOM 2000 no longer uses a clear text communications channel, and all traffic between the MOM agent and the MOM server is encrypted over TCP port 1270 . The MOM Administrator console uses DCOM to connect to the server . This means that administrators who manage the MOM server over the network must have access to random high TCP ports.

System service name: one point

Microsoft POP3 Service

Microsoft POP3 Service provides e-mail transfer and retrieval services. Administrators can use this service to store and manage e-mail accounts on the mail server. When you install Microsoft POP3 Service on the mail server, users can connect to the mail server and can retrieve e-mail by using an e-mail client that supports the POP3 protocol, such as Microsoft Outlook.

System service name: POP3SVC

MSSQLSERVER

MSSQLSERVER is a system service in Microsoft SQL Server 2000. SQL Server provides a powerful and comprehensive data management platform. You can configure the ports that each instance of SQL Server uses by using the Server Network Utility.

System service name: MSSQLSERVER

MSSQL$UDDI

The MSSQL$UDDI system service is installed during the installation of the Universal Description, Discovery, and Integration (UDDI) feature of the Windows Server 2003 family of operating systems. MSSQL$UDDI provides UDDI capabilities in an enterprise. The SQL Server database engine is the core component of MSSQL$UDDI.

System service name: MSSQLSERVER

Net Logon

The Net Logon system service maintains a security channel between your computer and the domain controller to authenticate users and services . It passes the user's credentials to a domain controller and returns the domain security identifiers and user rights for the user . This is typically referred to as pass-through authentication . Net Logon starts automatically when the computer is a member of a domain . In the Windows 2000 Server and Windows Server 2003 families, Net Logon publishes service resource records in the DNS. Net Logon is only enabled on computers that belong to a domain. When this service runs, it relies on the Server service and on the Local Security Authority service to listen for incoming requests. On domain member computers, Net Logon uses RPC over named pipes. On domain controllers, it uses RPC over named pipes, RPC over TCP/IP, mailslots, and Lightweight Directory Access Protocol (LDAP).

System service name: Netlogon

NetMeeting Remote Desktop Sharing

The NetMeeting Remote Desktop Sharing system service allows authorized users to remotely access your Windows desktop from another personal computer over a corporate intranet by using Windows NetMeeting. You must explicitly enable this service in NetMeeting. You can disable or shut down this feature by using an icon in the Windows notification area.

System service name: mnmsrvc

Network News Transfer Protocol (NNTP)

The Network News Transfer Protocol (NNTP) system service allows computers that are running Windows Server 2003 to act as news servers. Clients can use a news client, such as Microsoft Outlook Express, to retrieve newsgroups from the server and to read the headers or the bodies of the articles in each newsgroup.

System service name: NNTPSVC

Performance Logs and Alerts

The Performance Logs and Alerts system service collects, based on preconfigured schedule parameters, performance data from local or remote computers and then writes that data to a log or triggers a message. Based on the information that is contained in the named log collection setting, the Performance Logs and Alerts service starts and stops each named performance data collection. This service only runs if at least one performance data collection is scheduled.

System service name: SysmonLog

Print Spooler

The Print Spooler system service manages all local and network print queues and controls all print jobs. Print Spooler is the center of the Windows printing subsystem. It manages the print queues on the system and communicates with printer drivers and input/output (I/O) components, such as the USB port and the TCP/IP protocol suite.

System service name: Spooler

Remote Installation

You can use the Remote Installation system service to install Windows 2000, Windows XP, and Windows Server 2003 on Pre-Boot eXecution Environment (PXE) remote boot-enabled client computers . The Boot Information Negotiation Layer (BINL) service, the primary component of Remote Installation Server (RIS), answers PXE client requests, checks Active Directory for client validation, and passes client information to and from the server . The BINL service is installed when you either add the RIS component from Add/Remove Windows Components, or select it when you initially install the operating system.

System service name: BINLSVC

Remote Procedure Call (RPC)

The Remote Procedure Call (RPC) system service is an interprocess communication (IPC) mechanism that enables data exchange and invocation of functionality that reside in a different process . The different process can be on the same computer, on the LAN, or in a remote location, and can be accessed over a WAN connection or over a VPN connection . The RPC service serves as the RPC endpoint mapper and Component Object Model (COM) Service Control Manager . Many services depend on the RPC service to start successfully.

System service name: RpcSs

Remote Procedure Call (RPC) Locator

The Remote Procedure Call (RPC) Locator system service manages the RPC name service database. When this service is turned on, RPC clients can locate RPC servers. This service is turned off by default.

System service name: RpcLocator

Remote Storage Notification

The Remote Storage Notification system service notifies users when they read from or write to files that are only available from a secondary storage media. Stopping this service prevents this notification.

System service name: Remote_Storage_User_Link

Remote Storage Server

The Remote Storage Server system service stores infrequently used files on a secondary storage medium. If you stop this service, users cannot move or retrieve files from the secondary storage media.

System service name: Remote_Storage_Server

Routing and Remote Access

The Routing and Remote Access service provides multiprotocol LAN-to-LAN, LAN-to-WAN, VPN, and NAT routing services. Additionally, the Routing and Remote Access service also provides dial-up and VPN remote access services. Although Routing and Remote Access can use all the following protocols, the service typically uses only a subset of them. For example, if you configure a VPN gateway that lies behind a filtering router, you will probably use only one technology. If you use L2TP with IPSec, you must allow IPSec ESP (IP protocol 50), NAT-T (TCP on port 4500), and IPSec ISAKMP (TCP on port 500) through the router.

Note Although NAT-T and IPSec ISAKMP are required for L2TP, these ports are actually monitored by the Local Security Authority. For additional information about this, see the "References" section of this article.

System service name: RemoteAccess

Server

The Server system service provides RPC support and file, print, and named pipe sharing over the network . The Server service allows the sharing of local resources, such as disks and printers, so that other users on the network can access them . It also allows named pipe communication between programs that are running on the local computer and on other computers . Named pipe communication is memory that is reserved for the output of one process to be used as input for another process . The input-accepting process does not have to be local to the computer.

System service name: lanmanserver

SharePoint Portal Server

With the SharePoint Portal Server system service, you can develop an intelligent portal that seamlessly connects users, teams, and knowledge so that people can take advantage of relevant information across business processes. Microsoft SharePoint Portal Server 2003 provides an enterprise business solution that integrates information from various systems into one solution through single sign-on and enterprise application integration capabilities.

Simple Mail Transfer Protocol (SMTP)

The Simple Mail Transfer Protocol (SMTP) system service is an e-mail submission and relay agent. It accepts and queues e-mail for remote destinations, and it retries at specified intervals. Windows domain controllers use the SMTP service for intersite e-mail-based replication. The Collaboration Data Objects (CDO) for the Windows Server 2003 COM component can use the SMTP service to submit and to queue outbound e-mail.

System service name: SMTPSVC

Simple TCP/IP Services

Simple TCP/IP Services implements support for the following protocols:

System service name: SimpTcp

SMS Remote Control Agent

SMS Remote Control Agent is a system service in Microsoft Systems Management Server (SMS) 2003. SMS Remote Control Agent provides a comprehensive solution for change and for configuration management for the Microsoft operating systems. With this solution, organizations can provide relevant software and updates to users.

System service name: Wuser32

SNMP Service

SNMP Service allows incoming Simple Network Management Protocol (SNMP) requests to be serviced by the local computer . SNMP Service includes agents that monitor activity in network devices and report to the network console workstation . SNMP Service provides a method of managing network hosts (such as workstation or server computers, routers, bridges, and hubs) from a centrally-located computer that is running network management software . SNMP performs management services by using a distributed architecture of management systems and agents.

System service name: SNMP

SNMP Trap Service

SNMP Trap Service receives trap messages that are generated by local or by remote SNMP agents and then forwards those messages to SNMP management programs that are running on your computer . SNMP Trap Service, when configured for an agent, generates trap messages if any specific events occur . These messages are sent to a trap destination . For example, an agent can be configured to initiate an authentication trap if an unrecognized management system sends a request for information . Trap destinations include the computer name, the IP address, or the Internetwork Packet Exchange (IPX) address of the management system . The trap destination must be a network-enabled host that is running SNMP management software.

System service name: SNMPTRAP

SQL Analysis Server

The SQL Analysis Server system service is a component of SQL Server 2000. With SQL Analysis Server, you can create and manage OLAP cubes and data mining models. The analysis server may access local or remote data sources for creating and storing cubes or data mining models.

SQL Server: Downlevel OLAP Client Support

This system service is used by SQL Server 2000 when the SQL Analysis Server service has to support connections from downlevel (OLAP Services 7.0) clients. These are the default ports for OLAP services that are used by SQL 7.0.

SSDP Discovery Service

SSDP Discovery Service implements Simple Service Discovery Protocol (SSDP) as a Windows service . SSDP Discovery Service manages receipt of device presence announcements, updates its cache, and passes these notifications along to clients with outstanding search requests . SSDP Discovery Service also accepts registration of event callbacks from clients, turns these into subscription requests, and monitors for event notifications . It then passes these requests along to the registered callbacks . This system service also provides hosted devices with periodic announcements. Currently, the SSDP event notification service uses TCP port 5000. Starting with the next Windows XP service pack, it will rely on TCP port 2869.

Note At the time of this writing, the current Windows XP service pack level is Windows XP Service Pack 1 (SP1).

System service name: SSDPRSR

Systems Management Server 2.0

Microsoft Systems Management Server (SMS) 2003 provides a comprehensive solution for change and configuration management for Microsoft operating systems. With this solution, organizations can provide relevant software and updates to users quickly and cost-effectively.

TCP/IP Print Server

The TCP/IP Print Server system service enables TCP/IP–based printing by using the Line Printer Daemon (LPD) protocol. The LPD service on the server receives documents from Line Printer Remote (LPR) utilities that are running on UNIX computers.

System service name: LPDSVC

Telnet

The Telnet system service for Windows provides ASCII terminal sessions to Telnet clients. A Telnet server supports two types of authentication and supports the following four types of terminals:

American National Standards Institute (ANSI)
VT-100
VT-52
VTNT

System service name: TlntSvr

Terminal Services

Terminal Services provides a multi-session environment that allows client devices to access a virtual Windows desktop session and Windows-based programs that are running on the server. Terminal Services allows multiple users to be connected interactively to a computer.

System service name: TermService

Terminal Services Licensing

The Terminal Services Licensing system service installs a license server and provides licenses to registered clients when the clients connect to a terminal server (a server that has Terminal Server enabled). Terminal Services Licensing is a low-impact service that stores the client licenses that have been issued for a terminal server, and then tracks the licenses that have been issued to client computers or terminals.

System service name: TermServLicensing

Terminal Services Session Directory

The Terminal Services Session Directory system service allows clusters of load-balanced terminal servers to correctly route a user's connection request to the server where the user already has a session running . Users are routed to the first-available terminal server, regardless of whether they are running another session in the server cluster . The load-balancing functionality pools the processing resources of several servers by using the TCP/IP networking protocol . You can use this service with a cluster of terminal servers to increase the performance of a single terminal server by distributing sessions across multiple servers . Terminal Services Session Directory keeps track of disconnected sessions on the cluster and makes sure that users are reconnected to those sessions.

System service name: Tssdis

Trivial FTP Daemon

The Trivial FTP Daemon system service does not require a user name or a password and is an integral part of RIS. The Trivial FTP Daemon service implements support for the Trivial FTP Protocol (TFTP) that is defined by the following RFCs:

RFC 1350 - TFTP
RFC 2347 - Option extension
RFC 2348 - Block size option
RFC 2349 - Timeout interval, and transfer size options

TFTP is a file transfer protocol that is designed to support diskless boot environments. TFTP daemons listen on UDP port 69 but respond from a randomly allocated high port. Therefore, when you enable this port, the TFTP service can receive incoming TFTP requests, but enabling it does not allow the selected server to respond to those requests. You must configure the selected server to respond from port 69 to allow it to respond to inbound TFTP requests.

System service name: tftpd

Universal Plug and Play Device Host

The Universal Plug and Play Host discovery system service implements all the components that are required for device registration, control, and the response to events for hosted devices . The information that is registered that pertains to a device (the description, the lifetimes, and the containers) are optionally stored to disk and are announced on the network after registration, or when the operating system restarts . The service also includes the Web server that serves the device, in addition to service descriptions and a presentation page.

System service name: UPNPHost

Windows Internet Name Service (WINS)

Windows Internet Name Service (WINS) enables NetBIOS name resolution. This service helps you locate network resources by using NetBIOS names. WINS servers are required unless all domains have been upgraded to the Active Directory directory service and unless all computers on the network are running Windows 2000 or later. WINS servers communicate with network clients by using NetBIOS name resolution. WINS replication is only required between WINS servers.

System service name: WINS

Windows Media Services

Windows Media Services in Windows Server 2003 replaces the following four services that are included in Windows Media Services versions 4.0 and 4.1:

Windows Media Monitor Service
Windows Media Program Service
Windows Media Station Service
Windows Media Unicast Service

Windows Media Services is now a single service that runs on Windows Server 2003, Standard Edition; Windows Server 2003, Enterprise Edition; and Windows Server 2003, Datacenter Edition. Its core components were developed by using the COM, and it has a flexible architecture that you can customize for specific programs. It supports a greater variety of control protocols, including Real Time Streaming Protocol (RTSP), Microsoft Media Server (MMS) protocol, and HTTP.

System service name: WMServer