Netsh

Netsh is an incredibly valuable tool for anyone needing to debug network applications. With this software, you'll have the ability to dump incoming packets in both ascii or hexadecimal formats. You can also create custom packets and send them in either format as well. Additionally, the tool is built to forward the dumped packets. It was designed to be inserted between a client and a server application, but it can be utilized in other ways too.

Netsh uses a range of objects called devices which include sockets, files, the system console, and memory buffers. Each device can link to another device, which allows it to receive and send any data that the device does.

The package also provides a suite of simpler commands like hextelnet, tcpsrv, and udplink. These commands simplify the forwarding of packets to any number of hosts while dumping them and logging them in a file simultaneously.

While the benefits of Netsh are undeniable, it's important to note that this is still alpha software. As such, there are still many areas that can be improved. The website lacks detail, Netsh isn't documented thoroughly, and there's presently no error-checking within the code. Therefore, each system call, such as listen(), connect(), etc., must succeed for Netsh to work correctly.