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commincation via mac address

Hi all, is it possible for network devices to communicate only via mac address, or does ip need to be involved somewhere ?

Community Member

Re: commincation via mac address

No. Thats why it's called a protocol stack. Your Application layer communicates with tcp/udp - and these two can't talk to layer 2 without translator: IP

PS: of course it all depends on how you would define device, and communicate - Two Cisco devices can communicate with CDP over layer 2 for example.

Regards Robert

Community Member

Re: commincation via mac address

we have a phone system that does that have ip and just uses mac address, how does thsi work then, would each mac address have to be entered in each device to allow commuincation ?

Community Member

Re: commincation via mac address

I dont really get your setup. Somehow you have to map an identity (TelephoneNr or IP) to a Layer 2 ID. Maybe you are using a proprietary protocol that runs on top of Ethernet. You dont need an IP or IPX Layer - though it has prooved to be pretty convenient and succesful.

I dont understand "that does that have ip" -it does or does not? And it is an Ethernet Network?



Re: commincation via mac address

As per my understanding goes Network devices cannot communicate using mac-address.

The layer 2 devices ex. bridge and switches can learn about the network devices using mac-address. There will be no communication of frames in this case its only learning stage for the network device. In case the frame is recived will be forwared to the designation mac-address.

to the above there should be an ip address that would be assigned to the device for the forwarding to complete. In local LAN there can be commucation using mac-address but it will not be outside the domain.

I feel that ip address need to be involved to get the communication complete in a network.

I dont know much about the voice phone but seems to be it must be getting the ip address from some server if you have not assigned it any. You can check the switch config for the port which the ip phone is connected.

One more thing which you need to try is to disconnect the ip phone cable and connect to the laptop. do a ipconfig and check if you get an ip address.

Let me know if this helps.

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