The "normal" way is to have one keypair per device you use (unless using a key on a USB stick or something like that) and use that key for everything you do fro

The "normal" way is to have one keypair per device you use (unless using a key on a USB stick or something like that) and use that key for everything you do from that device (private, professional, etc.) The key identifies you physically (not as an employee, open source contributor or whatever, specifically). And the reason for having different ones in different devices is that it's more secure to generate on each device without leaking it during transfer. This way you can revoke the keys per device (e.g. you lose your laptop or have it stolen, revoke the key user@laptop and not the one user@university-lab). I use the same passphrase everywhere (but, again, they're different keys).