Sending files via FTP without IP addresses on PC's

Question

Can two PC's communicate with each other - FTP, without using IP addresses(entirely skipping Network Layer)? I know, FTP is client-server architecture, but I wonder if LAN network and MAC addresses are known, then technically two PC's can communicate via only NIC - MAC addresses, as a result there is no need for IP address in order two PC's could send files via ftp. I ask, because I read that Network Layer exists to provide logical address to facilitate path determination for routers, then theoretically in small LAN without a need for Internet access, IP address for those PC's seems to be unneccesary.

Answer 1

Short answer: No.

Long answer: The Open Systems Interconnection model ("OSI model") is here to help you understand networking infrastructure. When OSI is understood properly, all questions like this will answer itself.

Basically, OSI defines 7 Layers of stuff, on which the next higher level builds upon. Without the underlying Layer, the next Layers can not work. Layer 2 can not operate without Layer 1, Layer 3 can not work without 2 (which needs Layer 1) and so on.

FTP operates, as an application (or application protocol, to be exact), on Layer 7. This means, Layer 1-6 are needed for FTP to work. While IP is on Layer 3, Layer 4 is needed to transport information contained in Layer 3. So the complete Stack (1-Cable, 2-MAC, 3-IP, 4-TCP, 5-Session and finally 6-FTP) is needed.

While two machines can connect to each other using their MAC-Adresses, you will need a protocol to do stuff. There are ancient protocols that can exchange data at Layer 2 (we all remeber NetBEUI, right?), but "Layer 2 only" has been proven extremely unreliable and is practically not used anywhere.

Answer 2

you can create an ad-hoc network but you will not bypass the network layer. So basically you will use FTP without the internet in your local network.

you can try it by connecting two PCs with an ethernet cable. Statically assign different IP addresses for both PC (make sure that they are on the same subnet)

PC1: 192.168.1.2/24

PC2: 192.168.1.3/24 

So this answer will help you in case you want to transfer files between two PCs when directly connecting them together. but you are following the OSI model as well.

both ethernet interfaces have MAC addresses and you assigned IP addresses as well for the network layer, and then you can use FTP protocol to transfer files between them.

Answer 3

No, FTP cannot operate on top of Layer 2.

FTP relies on reliable stream transmission mechanisms provided by TCP. TCP in turn relies on packet transmission features provided by IP.

One could create a protocol that would transfer data from host to host using L2 Ethernet frames. However, that protocol would have to implement similar features as IP / TCP have in order to actually transfer files.