i have an ubuntu server and i just have installed ntopng on it for control all the network traffic on my server.
I noticed that ntopng sorts the hosts by access point (with the MAC address) but as i understand an access point is a router
Then i’m a bit confuse because when i check my ip, i have an access point associate and that access point has a lot of other IPs that obviously are not connected to my router.
When i go to my ip info i see that access point and when i click on it it shows me all the hosts related to that access point (image)
What i am misunderstanding?
Answer
This table doesn’t show anything about access points, quite the opposite. (Access points are Ethernet bridges, so packets sent through one do no inherit the AP’s MAC address.)
However, packets sent through a router do use the router’s own MAC address – the router will “rebuild” the packets and will not preserve the original MAC header. Similarly, when you send packets to remote hosts (any random host on the Internet), you do so by specifying that they should be sent to the router’s MAC, not the destination host’s MAC.
In other words, the packets your computer sends look like this:
Ethernet header:
Source MAC: <Your computer's MAC>
Destination MAC: <The router/gateway's MAC>
IPv4 header:
Source IP: <Your computer's IP>
Destination IP: <The website's IP>
And packets you receive from the router are the opposite – they have the website’s IP address as the IP source, but they always have the router’s MAC address as the Ethernet source.
As a result, every single remote host that you communicate with will appear as having the router’s MAC address. So the table you’re seeing is completely useless, but also completely normal.
Attribution
Source : Link , Question Author : Jaume Garcia Sanchez , Answer Author : user1686
