Copyright belongs to the author.
Commercial reprint please contact the author for authorization, non-commercial reprint please specify the source.
Vincent Wang
Links: http://www.zhihu.com/question/20583641/answer/20242980
Source: Know
The main meaning is popular, originally uploaded several layers of model, know that the map is too difficult, perhaps I upload the method is not right, the other often used ID audit has been through, look at the sky.
OSI model is mainly used as a general model to do theoretical analysis, and the TCP/IP protocol model is the actual communication protocol of the Internet, the two generally do mapping analysis, the following do not make strict distinctions and statements (well, lazy);
The OSI model hierarchy can be broadly divided into 3 main levels
|............. The host ........ | Applications, representations, sessions, such as operating systems and software
|............. The network ........ | Internet and related protocol transmission, Network (TCP/IP)
|............. The medium ........ | Physical media-related data links, physical
model for OSI
1, the host needs network transmission data,
The network is essentially a service, and the interface between the host and the network depends on the transport layer, it's like you're going to send something by courier;
2, the network can provide two kinds of services:
1) Reliable, connection-oriented; (TCP) is like a dependable courier, every step has feedback and monitoring, of course, the price is hehe ...
2) unreliable, best-effort transmission (UDP) is like some of the non-reliable express or listen to the XX Express, the price is low, but can be relied on luck.
3, two services do not have the so-called good or bad, TCP reliability is the need to consume a lot of resources, low efficiency (chunks, important documents, etc.)
UDP does not guarantee reliability, but high efficiency (video, voice, unimportant small files, etc.)
4, while the other "
HTTP, FTP, SMTP and so on so-called "Application-layer Protocol" protocolRefers to the application of specific functions in the framework of TCP/IP communication protocol (HTTP is used for Hypertext transfer, FTP file transfer, SMTP processing mail, etc.), the relationship between the two, cough, the relationship between the popular said:
TCP and UDP and IP protocols are the basis of Internet communication, like the Constitution, and application agreements are like specific criminal law, Civil Code, marriage law, the Protection of Minors Act ... And so on, in a certain area of the specific application and implementation, but the most basic one: unconstitutional invalid.
the model is a TCP/IP stack
TCP/UDP protocol, and HTTP, FTP, SMTP
