TCP Spy .NET is a small application used to trace TCP packets between a client and a server. Optimized for.Net Web Services or Web Site TCP Spy .Net will help you find any bottleneck and it will help you in analyzing your bandwidth usage.

Client/Server C++ component library for TCP/IP winsock sockets network communication. Allows multiple servers and clients to run simultaneously over a TCP network such as the Internet or intranet (LAN). Works with C++,C#.NET, MFC and C++ Builder.

Client/Server component VB and VB.NET library for TCP/IP winsock sockets network communication. Allows multiple servers and clients to run simultaneously over a TCP network such as the Internet or intranet (LAN). Works with Visual Basic and VB .NET

SmartSniff allows you to capture TCP/IP packets that pass through your network adapter, and view the captured data as sequence of conversations between clients and servers.

A "Must have" quick reference for IT/Networking professionals and students who are learning and using TCP/IP; Comprehensive Protocol Map focus on TCP/IP protocol suite and key layer 1 and 2 LAN, WAN an MAN protocols; Detailed explanations of IP.

This application security test tool gives developers an environment for testing non-HTTP Client/Server applications, similar to that provided by interactive HTTP proxies.

Communicate directly with an open TCP or UDP port on a machine. This can be very useful for low-level troubleshooting of server issues when using any of the clear-text based protocols such as FTP, Telnet, HTTP, etc. Also a great learning tool. (Free)

XP TCP/IP Repair is a Graphical User Interface (GUI) for commands in Windows XP® that repair your TCP/IP registry settings and your Winsock LSP's.