7 layers of osi model

variety of applications that can complete and implement the various services requested by the user. Summary of OSI7 layer modelSince OSI is an ideal model, the general network system involves only a few layers, and few systems can have all 7 layers and fully comply with its

layer here?The OSI model is a layered model, that is, it is divided into several parts, each of which is called a layer, each layer plays a fixed role, as seen in:650) this.width=650; "Src=" https://mmbiz.qlogo.cn/mmbiz/ iahl5mqlicpynj6o78bkudfel4pys77dv4niv6aastde8bioyfpm3y7lul0oicsou3pvlbch3s0wd5skocyezj6ca/0 "style=" Height:auto ; "alt=" 0 "/>

TCP/IP four layer modelTCP/IP is synonymous with a set of protocols, and it also includes many protocols that make up the TCP/IP protocol cluster. TCP/IP protocol cluster is divided into four layers, IP is located in the second layer of the Protocol cluster (corresponding to the third layer of OSI), TCP is located in the third layer of the Protocol cluster (corresponding to the fourth layer of

completed by different application protocols and programs of this layer, and the differences between different network operating systems in the functions, interfaces, implementation technologies, hardware support, security reliability and various application interfaces are very large. The main functions of the application layer are as Follows:User interface: The application layer is a direct interface between the user and the network, and the application and the network, allowing the user to in

, File transfer Service (FTP), Remote Login service (telnet), e-mail Service (email), Print service, security Service, network Management Service, database service, and so on. The various network services mentioned above are completed by different application protocols and programs of this layer, and the differences between different network operating systems in the functions, interfaces, implementation technologies, hardware support, security reliability and various application interfaces are v

function, interface, implementation technology, hardware support, security and reliability, as well as a variety of application interfaces and other aspects of the difference is very large. The main functions of the application layer are as follows:user interface: The application layer is a direct interface between the user and the network, and the application and the network, so that users can interact with the network interactively.implement a variety of services: This layer has a variety of

are completed by different application protocols and programs of this layer, and the differences between different network operating systems in the functions, interfaces, implementation technologies, hardware support, security reliability and various application interfaces are very large. The main functions of the application layer are as follows:User interface: The application layer is a direct interface between the user and the network, and the application and the network, allowing the user t

), i.e. the ISO open Interconnect system Reference Model. Such as. Each layer implements its own functions and protocols, and communicates with the interfaces of the neighboring layers. The OSI service definition provides a detailed description of the services provided at each level. A layer of service is the ability of the layer and its lower

expand the function independently according to the need, meanwhile, it is advantageous to the interconnection of equipment of different manufacturers, and also helps us to learn and understand the data communication network.Different layers in the OSI reference model perform different functions, and each layer communicates with each other through a standard inte

/IP protocol are hierarchical and are based on the concept of a separate protocol stack. The OSI Reference Model has 7 layers, and the TCP/IP protocol has only 4 layers, that is, the TCP/IP protocol does not have a presentation layer and a session layer, and merges the data

ISO open Interconnect system Reference Model. Such as. each layer implements its own functions and protocols, and communicates with the interfaces of the neighboring layers. The OSI service definition provides a detailed description of the services provided at each level. A layer of service is a capability of the layer and its lower

The OSI reference model has many similarities with the TCP/IP reference model. They are based on the concept of an independent protocol stack. In addition, the features of the layer are similar. For example, in the two models, the transmission layer and above all provide end-to-end and network-independent transmission services for processes that want to communica

protocol are hierarchical and are based on the concept of a separate protocol stack. The OSI Reference Model has 7 layers, and the TCP/IP protocol has only 4 layers, that is, the TCP/IP protocol does not have a presentation layer and a session layer, and merges the data lin

devices. . A method that ensures that network transmissions are received correctly. . How network devices maintain a constant rate of data flow. . How the electronic data is represented on the network media. The OSI model consists of 7 layers of layers: physical layer,

more and more complex, and the network devices between the manufacturers are mostly incompatible and difficult to communicate.In order to solve the network compatibility problems, to help manufacturers to produce compatible network equipment, ISO in 1984, the OSI RM (Opensystem interconnection Reference model, open System Interconnect Reference Model). The

Reasons for the existence of the OSI model (open System interconnection):The network model is built so that the builders of the network can build networks that can communicate and work with each other, and describe the transmission of data from one computer to another on a network.1.physical LayerDefines the electronic and functional aspects of the connection bet

permissions is compromised; bodyAuthentication and session management is compromised; cross-site vulnerability to code execution, cache overflow vulnerability, pop-up vulnerability, error handlingImproper, unsafe storage, denial of service, unsafe configuration management. Network isolation must split the application protocol.All network attacks must reside on a layer of the network OSI model, otherwise it

650) this.width=650; "src=" Http://s1.51cto.com/wyfs02/M00/86/CA/wKioL1fK0vaCHA2_AAHY47KSUjM920.jpg "title=" 001ttetlgy6ocxvcbca94690.jpg "alt=" Wkiol1fk0vacha2_aahy47ksujm920.jpg "/> OSI seven-layer model Open Systems Interconnect (open System interconnect), the model is divided into 7

Everyone who has studied computer networks must know the OSI seven layer protocol model. The OSI layer Seven protocol model (or OSI seven layer model) is a well-defined protocol specification and is considered a standard reference

IntroductionOSI (open System interconnect), which is open systems interconnection. Commonly called the OSI Reference Model, is the network interconnection model that the ISO (International Organization for Standardization) organization studied in 1985, which gives you an introduction to the OSI Reference