Introduction.

Microsoft has adopted TCP/IP as the strategic enterprise network transport for its platforms. In the early 1990s, Microsoft started an ambitious project to create a TCP/IP stack and services that would greatly improve the scalability of Microsoft networking. With the release of the Microsoft® Windows NT® 3.5 operating system, Microsoft introduced a completely rewritten TCP/IP stack. This new stack was designed to incorporate many of the advances in performance and ease of administration that were developed over the past decade. The stack is a high-performance, portable 32-bit implementation of the industry-standard TCP/IP protocol. It has evolved with each version of Windows NT to include new features and services that enhance performance and reliability.

The goals in designing the TCP/IP stack were to make it:

• Standards-compliant
• Interoperable
• Portable
• Scalable
• High performance
• Versatile
• Self-tuning
• Easy to administer
• Adaptable

This paper describes Windows 2000 implementation details and is a supplement to the Microsoft Windows 2000 TCP/IP manuals. It examines the Microsoft TCP/IP implementation from the bottom up and is intended for network engineers and support professionals who are familiar with TCP/IP.

This paper uses network traces to help illustrate concepts. These traces were gathered and formatted using Microsoft Network Monitor 2.0, a software-based protocol tracing and analysis tool included in the Microsoft Systems Management Server product. Windows 2000 Server includes a reduced functionality version of Network Monitor. The primary difference between this version and the Systems Management Server version is that the limited version can only capture frames that would normally be seen by the computer that it is installed on, rather than all frames that pass over the network (which requires the adapter to be in promiscuous mode). It also does not support connecting to remote Network Monitor Agents.