# nmap is a powerful network scanning tool that should be a standard item in your tool box
cd /usr/ports/security/nmap
make install clean
# Example:
# nmap v sV -O -p 21,135,139,445,5800,5900 www.netjunkies.net

# nmapfe is a frontend GUI for nmap to make life simpler
cd /usr/ports/security/nmapfe
make install clean
# Example:
# nmapfe &

# dnstracer determines where a given Domain Name Server (DNS) gets its information
cd /usr/ports/dns/dnstracer
make install clean
# Example:
# dnstracer www.netjunkies.net

# dhcping sends a DHCP request to DHCP server to see if it's up and running
cd /usr/ports/net/dhcping
make install clean
# Example:
# dhcping -v 172.28.0.10

# echoping tests performances of a remote host by sending it TCP "echo" (or other protocol) packets
cd /usr/ports/net/echoping
make install clean
# Example:
# echoping -h / www.netjunkies.net:80

# fping is meant to be used in scripts and its output is easy to parse
cd /usr/ports/net/fping
make install clean
# Examples:
# fping -g 172.28.0.0/24
# fping -a -g 172.28.0.0/24

# hping is a command-line oriented TCP/IP packet assembler/analyzer
cd /usr/ports/net/hping
make install clean
# Example:
# hping --scan 1-1024 -S 172.28.0.10

# ngrep can be used to debug various plain text protocols like HTTP and FTP etc.
cd /usr/ports/net/ngrep
make install clean
# Example:
# ngrep port 80

# netcat is the tcp/ip "Swiss Army knife"
cd /usr/ports/net/netcat
make install clean
# Examples:
# nc -v www.netjunkies.net 80 (and type: GET / HTTP/1.0)
# nc -v www.netjunkies.net 80 < get.txt

# wget is for retrieving files using HTTP, HTTPS and FTP mostly used by scripts or at the command line
cd /usr/ports/ftp/wget
make install clean
# Example:
# wget http://members.netjunkies.net/n3ncy/FreeBSD61/Useful-Network-Tools.htm