GP may be referring to the "TCP/IP model" which does indeed define the layers used in common parlance. This model has 4 layers in contrast to the OSI model's 7 layers. The TCP/IP model is closer to how most real life network stack implementations are defined.
Arguably even this layering system is too rigid for reality but it's a decent model. See RFC 3439 section 3.
Comments
Correction: the network stack has layers, where IP is one of them, near the top.
Which is why most software targets IP. It’s a good abstraction and it’s portable.
GP may be referring to the "TCP/IP model" which does indeed define the layers used in common parlance. This model has 4 layers in contrast to the OSI model's 7 layers. The TCP/IP model is closer to how most real life network stack implementations are defined.
Arguably even this layering system is too rigid for reality but it's a decent model. See RFC 3439 section 3.