What is IPv4? (TechRef)

Applies To: Windows Server 2008

What is TCP/IP?

Transmission Control Protocol/Internet Protocol, or TCP/IP, is an industry-standard suite of protocols designed for large internetworks. TCP/IP, which was developed in 1969 by the U.S. Department of Defense (DoD) Advanced Research Projects Agency (DARPA), is the result of a resource-sharing experiment called Advanced Research Projects Agency Network (ARPANET). The TCP/IP protocol was developed to provide high-speed communication network links. Since 1969, ARPANET has grown into a worldwide community of networks known as the Internet.

Before TCP/IP, there was no way for computers to communicate easily and securely on public networks. Windows Server® 2008 TCP/IP was designed to make it easy to integrate Microsoft systems into large-scale corporate, government, and public networks, and to provide the ability to operate over those networks in a secure manner. In Windows Server 2008, the TCP/IP protocol is installed by default and, unlike previous versions of Windows, cannot be uninstalled. However, you can reset the TCP/IP configuration to a default state with the netsh interface ip reset command.

The Windows TCP/IP suite contains core protocol elements, services, and the interfaces between them. The Transport Driver Interface (TDI) and the Network Device Interface Specification (NDIS) are public, and their specifications are available from Microsoft. In addition, there are a number of higher-level interfaces available to user-mode applications. The most commonly used are Windows Sockets and NetBIOS.

Windows Server 2008 TCP/IP

Windows Server 2008 TCP/IP enables enterprise networking and connectivity. Adding TCP/IP to a Windows Server 2008 configuration offers the following advantages:

  • A standard, routable enterprise networking protocol that is the most complete and accepted protocol available. All modern network operating systems offer TCP/IP support, and most large networks rely on TCP/IP for much of their network traffic.

  • A technology for connecting dissimilar systems. Many standard connectivity utilities are available to access and transfer data between dissimilar systems, including File Transfer Protocol (FTP) and Telnet, a terminal emulation protocol. Several of these standard utilities are included with Windows Server 2008.

  • A robust, scalable, cross-platform client/server framework. Windows Server 2008 TCP/IP offers the Windows Sockets interface, which is ideal for developing client/server applications that can run on Windows Sockets–compliant TCP/IP protocol implementations from other vendors.

  • A method of gaining access to the Internet. The Internet consists of thousands of networks worldwide, connecting research facilities, universities, libraries, private companies, and individuals.


The term Internet refers to the worldwide public Internet. An intranet refers to a private IP-based internetwork.

Support for Standard Features

Windows Server 2008 TCP/IP supports the following standard features:

  • Ability to bind to multiple network adapters with different media types.

  • Logical and physical multihoming.

  • Internal IP routing capability.

  • Internet Group Management Protocol (IGMP) (IP multicasting).

  • Duplicate IP address detection.

  • Multiple configurable default gateways.

  • Dead gateway detection.

  • Automatic Path Maximum Transmission Unit (PMTU) discovery.

  • Internet Protocol security (IPSec).

  • Quality of Service (QoS).

  • Virtual Private Networks (VPNs) with the Point-to-Point Tunneling Protocol (PPTP) and the Layer Two Tunneling Protocol with IPSec (L2TP/IPSec).

TCP/IP Standards

The standards for TCP/IP are published in a series of documents that are called Requests for Comments (RFCs). RFCs describe the internal workings of the Internet. Some RFCs describe network services or protocols and their implementations, whereas others summarize policies. TCP/IP standards are always published as RFCs, although not all RFCs specify standards.

TCP/IP standards are not developed by a committee, but rather by consensus. Anyone can submit a document for publication as an RFC. Documents are reviewed by a technical expert, a task force, or the RFC editor, and then assigned a status. The status specifies whether a document is being considered for becoming a standard.

There are five RFC status assignments, shown below.

RFC Status Assignments

Status Description


Must be implemented on all TCP/IP-based hosts and gateways.


Encouraged that all TCP/IP-based hosts and gateways implement the RFC specifications. Recommended RFCs are usually implemented.


Implementation is optional. Application has been agreed to but is not a requirement.

Limited Use

Not intended for general use.

Not Recommended

Not recommended for implementation.

If a document is being considered for becoming a standard, it goes through stages of development, testing, and acceptance known as the Internet Standards Process. These stages are formally labeled maturity levels. The following table lists the three maturity levels for Internet Standards.

Maturity Levels for Internet Standards

Maturity Level Description

Proposed Standard

This specification is generally stable, has resolved known design issues, is believed to be well understood, has received significant community review, and appears to hold enough community interest to be considered valuable.

Draft Standard

This must be well understood and known to be quite stable, both in its semantics and as a basis for developing an implementation.

Internet Standard

This specification is characterized by a high degree of technical maturity, and it is generally agreed that the specified protocol or service provides significant benefit to the Internet community.

When a document is published, it is assigned an RFC number. If changes are required, a new RFC is published with a new number. The original RFC is never updated. Therefore, it is important to verify that you have the most recent RFC on a particular topic.

RFCs can be obtained in several ways. To obtain any RFC, or a full and current indexed listing of all RFCs published to date, see the IETF RFC Database.