I recently got a new Mac laptop at work, and as part of setting it up, I wanted to add two of the printers on the office network. As I went through the process of setting them up, I tried to remember which printer protocol was the “right” one to use these days. And when I turned to Google, and then Bing, to try to find the answer, I discovered that this information just isn’t published anywhere online. (Is it just me, or are search results becoming more and more terrible?)
Apple’s own documentation isn’t helpful. It describes the three options, but makes no recommendations. So, here’s the answer, really simple:
1. If you have an HP printer, use HP Jetdirect – Socket.
2. For any other modern (less than 10 years old) networked printer, use Internet Printing Protocol – IPP.
3. If and only if that doesn’t work, try Line Printer Daemon – LPD.
The explanation is simple, too. If you have an HP printer, you want to use the HP-specific protocol. Otherwise, IPP is the modern printer network protocol (and it works with HP printers, too). LPD is actually pretty ancient, technology-wise, but there are still some printers, or print spoolers, that only work with it.