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[MiNT] OT: Re: Weird ping reply


Well, I understand how the HW address is assigned, but the point is that the ping doesn't work from the user point of view (Timeout) although the packets are actually sent and received on the NIF. That's why I am suspicious about the HW address. Also the HW address should be changed by the router to the destination one coresponding to the IP of the machine. Still don't understand what I am missing here.


Adam Klobukowski wrote:
Standa Opichal napisał(a):


OK, I found out that the HW address I am getting is my HUB's one. It seems that the bridge or the NAT in the HUB exchanged this. I don't know exactly why, but it is definitely not a mintnet fault.

Anyway, does anyone have idea what was it going there?

If I understand it correctly, addreses you shown are MAC adressed of the network cards (and aport in the hub). They are used by Ethernet protocols.

Ping howewer works on the higher level. It works on the IP protocol level.

When you ping or hust tty to connect something using IP protocol), your computer first uses ARP (Address resolution protocol) to question the network where to send packets. Why? Becouse IP addres may be world-wide, and MAC is locally. IP packets gets encapsulated into Ethernet packets, and then sent into network. But where? This is where ARP comes handy. ARP allows you to ask: "What is a MAC addres of the device that I sgould sent IP packets with the following IP address (ie. gateway)".

Maybe it is a bit complicated, and my english is not good enough, but basically this is how it works.