network-tools

What are your recommended tools and frameworks for network development on Linux?

What are your favourite network-tools, which you use to troubleshoot or design (as in conceptualize) your network-application code. Ethereal/Wireshark Nmap any particular simulators (e.g. ns) any special purpose sniffer any particular frameworks, (e.g. iptables) I am looking at must have, and good/advantage to have tools/framework ...

Are there any tool for monitoring HTTP response?

Are there any tool for monitoring HTTP responses? so open such tool up. give it URL. And it goes to it and brings you back not only body of http response but all http response. ...