I was teaching on onsite and the customer wanted to record the session so employees can have some material to review. I thought it would be helpful to share.
I always start with the OSI model - or my version of it.
I hate to complicate things, so I use a 4 layer model. As I go through it, I always get that asked, 'why bother with this?'.
I explain that the model helps people to work consistantly. Kind of like a checklist when troubleshooting, baselining or even a way to organize your report.