net6 is a library which eases the development of network-based applications
as it provides a TCP protocol abstraction for C++. It is portable to both
the Windows and Unix-like platforms.
Netcat is a simple Unix utility which reads and writes data across
network connections using TCP or UDP protocol. It is designed to be a
reliable "back-end" tool that can be used directly or easily driven by
other programs and scripts. At the same time it is a feature-rich
network debugging and exploration tool, since it can create almost any
kind of connection you would need and has several interesting built-in
capabilities.
Netdude is the NETwork DUmp data Displayer and Editor for tcpdump tracefiles.
It is a GUI-based tool that allows you to make detailed changes to packets in
tcpdump tracefiles.
Netmap can be used to make a graphical representation of the surrounding
network. It first uses traceroute to make a list of all routers and their
interconnections, after which it generates a .dot file.
NetStrain is a tool to measure practical data throughput between two machines
over a TCP connection. It can be used for performance testing,
stress/stability testing and to demonstrate various network effects. It
supports both IPv4 and IPv6, provided the underlying system does.
Neubot is a research project on network neutrality of the NEXA Center for
Internet & Society at Politecnico di Torino. The project is based on a
lightweight open-source program that interested users can download and install
on their computers. The program runs in background and periodically performs
transmission tests with some test servers and with other instances of the
program itself. These transmission tests probe the Internet using various
application level protocols. The program saves tests results locally and uploads
them on the project servers. The collected dataset contains samples from various
Providers and allows to monitor network neutrality.
ngrep strives to provide most of GNU grep's common features, applying
them to the network layer.
ngrep a pcap-aware tool that will allow you to specify extended
regular expressions to match against data payloads of packets. It
currently recognizes TCP, UDP, and ICMP across Ethernet, PPP, SLIP,
FDDI, Token Ring and null interfaces, and understands BPF filter
logic in the same fashion as more common packet sniffing tools,
like tcpdump and snoop.
OpenBGPD is a FREE implementation of the Border Gateway Protocol, Version 4.
It allows ordinary machines to be used as routers exchanging routes with
other systems speaking the BGP protocol.
The Packet Debugger (pdb) is a program which allows people to work
with packet streams as if they were working with a source code
debugger. Users can list, inspect, modify, and retransmit any packet
from captured files as well as work with live packet capture.