The TCP/IP model, in general, does not consider physical specifications, rather it assumes a working network infrastructure that can deliver media-level frames on the link.
Some textbook authors have supported the interpretation that physical data transmission aspects are part of the link layer.
[1][2] Others assumed that physical data transmission standards are not considered communication protocols, and are not part of the TCP/IP model.
The link layer in TCP/IP is still wider in scope and in principle a different concept and terminology of classification.
However, this use is misleading and non-standard, since the link layer implies functions that are wider in scope than just network access.