Traffic generators

1)D-ITG http://www.grid.unina.it/software/ITG/download.php

2)pacgen - Ethernet IP TCP/UDP packet generating tool for Linux
http://nixbit.com/cat/system/networking/pacgen/

3)Hping is a command-line oriented TCP/IP packet assembler/analyzer download

4)Nessus Vulnerability Scanner from Tenable Network Security download

5)Tcpreplay is to resend all packets from its input file(s) at the speed at which they were recorded, at some specified data rate download

6)Nemesis is a command-line network packet crafting and injection utility for for testing Network Intrusion System download

7)PackETH is a *graphical* packet generator tool for ethernet download

Network Monitor Analyzer

1)Wireshark Network Protocol Analyzer-Network protocol analyzer for Windows and Unix that allows examination of data from a live network, or from a capture file on disk
download

2)Ethereal- A Network Protocol Analyzer
download

3)EtherApe is a graphical network monitor for Unix modeled after etherman.Featuring link layer, ip and TCP modes, it displays network activity graphically download

4)SNORT-SNORT is an Open Source Intrusion Detection System download

5)Argus-designed to monitor servers and network connections download

6)ngrep is a "network grep" utility that can be used to match regular expressions within network packet payloads download

7)Nagios for network and service monitoring download

8)NetworkActiv to sniff webpages on a Wi-Fi network download