Here are the resources referenced in my 2018 JNUC session - Device Enrollment: under the hood
Apple Support Articles
Use Device Enrollment
TCP and UDP ports used by Apple Software
https://support.apple.com/HT202944
Get Started using Apple Business Manager with Mobile Device Management
If you aren’t getting Apple push notifications
If you service or replace a device in Apple School Manager or Apple Business Manager
Find Apple Customer Numbers, DEP Reseller ID and DEP Reseller ID
Apple Documentation
Apple System Status Page
Device Enrollment Program Guide
Apple Deployment Programs Help
Deployment Reference
MDM Protocol Reference
AppleCare Connect DEP API guide
Third party references
MicroMDM wiki - Troubleshooting MDM and DEP
Using Terminal at the setup assistant
Showing the language chooser screen after reinstalling macOS
AutoDMG
vfuse
Creating VMs that work with Device Enrollment
Duo Security - MDM Me Maybe
https://www.youtube.com/watch?v=lz6ikbC3Rdg
Demystifying MDM: open source endeavors to manage Macs - Jesse Peterson and Victor Vrantchan
Getting MicroMDM working and working with MicroMDM – Jesse Peterson
A Deep Dive into macOS MDM (and how it can be compromised)
A Push Odyssey: Journey to the Center of APNS | JNUC 2017
