OSI/RM is only a reference model and has not been really applied to the network.
Therefore, in order to communicate with heterogeneous networks, TCP/IP protocol must be installed.
If it is a fill-in-the-blank question, fill in TCP/IP protocol.
TCP/IP provides a point-to-point link mechanism, which standardizes how data should be encapsulated, addressed, transmitted, routed and received at the destination.
It abstracts the software communication process into four abstract layers, and realizes different communication protocols through the protocol stack.
According to their different functions, various protocols under the protocol family are divided into these four levels.
Extended data:
When a peer-to-peer process uses a protocol to communicate, it does not actually directly transfer data from the N layer of one machine to the N layer of another machine. Instead, each layer packages data together with its control information to the next layer, and the next layer packages these contents as data together with its control information to the next layer, and so on until the lowest layer.
The bottom layer is the physical medium, which performs the actual communication.
There are interfaces between adjacent layers, which define primitive operations and services provided by the bottom layer to the upper layer.
In order to exchange information between adjacent layers, peer-to-peer interfaces must have agreed rules.
The collection of layers and protocols is called network architecture.
TCP/IP protocol does not depend on any specific computer hardware or operating system, and provides an open protocol standard. Even without considering the Internet, TCP/IP protocol has been widely supported.
Therefore, TCP/IP protocol has become a practical system combining various hardware and software.
TCP/IP protocol does not depend on specific network transmission hardware, so TCP/IP protocol can integrate various networks.
Users can use Ethernet, token ring network, dial-up line, X.
Network and all network transmission hardware.