[CentOS] Monitor speed between client and server, netperf?

Hi,

Want to know what is the best tools to monitor network connection speed between client PC and my server. As I need to know if the network latency. I know use zabbix to monitor CPU/member and others of server. However, 1. For the connection speed monitor is there any tools can do this? 2. I tried netperf, it's good. I have to write a cron job in my client PC to report the speed? is this a correct way to do? 3. If use netperf and cron job do connection speed test every 5 mins, is that impact my server network throughput as I guess it is sending really data between server and client. Could you help to point me a right way to move on, thank you very much.

Best Regards, Su Heng