No, they are not the same at all. One page of text can explain the Async protocol. However, it takes a whole book to explain TCP/IP. In any network/communication book, you will see the layers of protocol, like physical layer, link layer, network layer, transport layer, and etc. In OSI model, the layer number can go up to 7 (application layer).

Say simply, RS232 defines the physical layer protocol, IP defines the network layer, and TCP defines the transport layer. In MS Windows, comm.drv handles the link layer communication. Basically, lower two layers deal with correct transmission of bits and bytes between communication devices, and higher layers deals with correct routing of packets/messages among network nodes.

Regards, Oliver