Case Analysis of Seven-tier Model

Case Analysis of Network Seven-layer Model

Send an email to a friend

1. Physical layer: establish, maintain, and disconnect physical connections. The transmission medium is the network cable.

two。 Data link layer: establish logical connection, hardware address addressing, error checking and other functions. That is the sending and receiving address of this email.

3. Network layer: logical address addressing and path selection between different networks. That is, the optimal route and sending scheme of the sending place and destination of the mail.

4. Transport layer: defines the protocol port number over which data is transmitted, as well as flow control and error checking. That is, the sender and recipient of the confirmation message.

5. Session layer: establish, manage, and abort sessions. Establish a relationship between the recipient and the sender.

6. Presentation layer: data representation, security, compression. That is, the way the mail is opened, the content, and so on.

7. Application layer: an interface between a network service and an end user. The interaction between mail and recipients.