Network Monitoring Tools

1. Nethogs

Install it by            sudo apt-get install nethogs

launch it by                sudo nethogs <connection_name> 

for example                sudo nethogs ppp0 

2. EtherApe
 
EtherApe is a graphical network monitor, which displays network activity graphically with showing active hosts as circles of varying size,and traffic among them as lines of varying width. In some cases your machine's NIC only sees packets going between your machine and the router. In that cases it is very uselful one to locate them.

 To intsall it by

sudo apt-get install etherape

3. Nagios

This is one of the most popular web bases linux monitoring system.

Homepage / Download Page: http://www.nagios.org/

4. Cacti

Cacti is another web based monitoring system written in PHP and licensed under GPL. Cacti was designed mainly to show results in graph formats.

Homepage / Download Page: http://www.cacti.net/

 

5. Zabbix

It's a  Open Source software Performance monitoring Agents for all platforms Agent-less monitoring Availability and SLA reporting Collection of any data Great graphs and network maps.

Homepage / Download Page : http://www.zabbix.com/

 

Simply use System Monitor to check you data transmission. Open it by 

If you have any queries, post it in comments. We will help you.