If I keep creating unrelated files, will the ipfs system run out of junk files? 
By default we use 256 bits hashing, this allows for 115792089237316195423570985008687907853269984665640564039457584007913129639936 different files to “exists” (*there are cryptographic limitations).
This is 3 order of magnitude close to the number of atoms in the visible universe, in other words a fucking lot.
But I keep sending 256 bits to ipfs, which can add up. Let other ipfs network members store junk files
The 256 bits is about the hash space.
You don’t send files to other nodes unless they ask for it. You can’t just use space in the network, IPFS is a file sharing network, that means you can exchange data, but if you shutdown your node the file wont be accessible because other nodes wont host it for you (most of the time).
If people decide to host your file then the other node will send it, but this is not an automated process, someone on the other node has to pin your file.
You can also use a pinning service, where you pay someone else to host the file for you.
ipfs seems to be an upgraded version of the BT network, ipfs is similar to different bt servers united into a ready-made whole. If the hosting server does not have a public ip address, ipfs will act as the transit server? I’m curious if I have a file that someone else needs, but I don’t have a public ip. How do I send files to others?
Thank you very much. I’m going to finish this video on ipfs