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Difference between recorded network traffic and downloaded file size?




I configured a NetFlow9 protokol on a firewall port. The network traffic is now beeing shown in PRTG. For a testing purposes I downloaded a zip file from the internet. The file size is 167 MB. But when I looked for this traffic in PRTG, the Top connections showed the traffic amount on port 80 for my IP address of 338 MB. I know these amounts shouldn´t be the same because of the way the sessions work but can the difference be so big (2x the size of downloaded file)?


netflow9 prtg top-connections

Created on Jun 28, 2018 6:46:39 AM

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Accepted Answer



Hello there,

Thanks for your inquiry, we appreciate your contact regarding this matter!

There are two interfaces through which the packets go through, so the traffic is counted twice here. They're ingress and egress flows. Please also take a look at this link for more information.

For any further questions or issues, we're glad to help.

Kind regards,
Birk Guttmann, Tech Support Team

Created on Jun 29, 2018 7:33:37 AM by  Birk Guttmann [Paessler Support]

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