I have recently been using telnet a lot recently to test out many different types of tcp connections, (basic TCP, standard HTTP, Bayeux through HTTP, etc) as a means to learn how things work.
I want to learn a little bit more about how the next layer down in the OSI model works by using a tool to learn things that happen at the network layer.
Just as telnet allows the sending of messages at the TCP layer to learn about what goes on in the layer above it, I want to use a tool that allows me to send IP packet messages to see what things the TCP layer does.
Does anyone have any suggestions for what tool I could use?