What is data encapsulation and decapsulation?

Data Encapsulation Data encapsulation refers to the transfer of protocol data units.

PDUs) encapsulated in a set of protocol headers and tails. In the OSI 7-layer reference model, each layer is primarily responsible for communicating with peers on other machines. This process is implemented in a "protocol data unit" (PDU), where the PDU of each layer is typically composed of the protocol header, protocol tail, and data encapsulation of that layer.

Each layer can add protocol headers and tails to their corresponding PDUs. The protocol header contains information about the communication between layers. Protocol headers, protocol tailers, and data are three relative concepts, depending on the layers at which the information unit analysis is performed.

For example, the transport header (th) contains only the transport layer.

information that can be seen, while all other layers below the transport layer transmit the transport header as part of the data for each layer. at the network layer.

An information unit consists of a layer 3 protocol header (NH) and data; and the data link layer.

, all information transmitted by the network layer (Layer 3 protocol headers and data) is considered data. In other words, the data portion of an information unit in a particular OSI layer may contain protocol headers, protocol tails, and data that are transferred down from the upper layer.

Data encapsulation, generally speaking, is to map business data to the payload of a certain encapsulation protocol, and then fill the header of the corresponding protocol to form a packet of the encapsulation protocol and complete rate adaptation.

Deencapsulation is the reverse process of encapsulation, disassembling the protocol package, processing the information in the packet header, and taking out the business information data in the payload Data encapsulation and decapsulation are a pair of reverse processes.

Data encapsulation refers to the process of encapsulating a protocol data unit (PDU) in a set of protocol headers and ends. In the OSI 7-layer reference model, each layer is primarily responsible for communicating with peers on other machines. This process is implemented in a "protocol data unit" (PDU), where the PDU of each layer is typically composed of the protocol header, protocol tail, and data encapsulation of that layer.

Extended data: When packets are transmitted between different devices using the network, in order to reliably and accurately send them to the destination, and to make efficient use of transmission resources (transmission equipment and transmission lines), the packets should be split and packaged in advance, and the destination address, local address, and some bytes for error correction should be appended to the sent packets, and when the security and reliability are high, encryption should be carried out, etc. These operations are called data encapsulation.

When processing packets, the rules that are followed and negotiated by both parties are agreements. Compared with mailing items, the data packet itself is like an item, and the encapsulation is like filling in various mailing information, and the agreement is the specification of how to fill in the information.

Encapsulation, that is, the properties and implementation details of objects are hidden, and only the interface is exposed to the outside world, and the access level of reading and modification of properties in the program is controlled; Combine the abstracted data and behaviors (or functions) to form an organic whole, that is, the data is organically combined with the source of the operating data to form a "class", in which the data and functions are members of the class. In electronics, packaging refers to the circuit pins on the silicon wafer that are wired to the external connector to connect with other devices.

Encapsulation is encapsulation, which means air belt in the middle and late stages of uh production, this air duct is the worst product, and it is a final kind of packaging, so this kind of packaging must be sealed.

If you put it in a package, it should be based on its main points and according to your own meaning.

This refers to the fact that we produce a product, that is, we need to seal the product, that is, to seal the outside of it.

The process of data decapsulation is (Pedan).

a.Segment – Packet – Frame – Stream – Data.

b.Stream—Frame—Packet—Segment—Data.

c.Data header-package-segment-in-frame annihilation-stream.

d.Data—Segments—Packets—Frames—Streams.

Correct answer: B

Packaging is the process of assembling an integrated circuit into a chip final product, simply put, it is to put the integrated circuit die (die) produced by foundry on a substrate that plays a bearing role, lead the pins out, and then fix the packaging as a whole.

Because the chip must be isolated from the outside world to prevent the corrosion of the chip circuit by impurities in the air and cause the electrical performance to deteriorate. On the other hand, the packaged chip is also easier to install and transport. It is crucial because the quality of packaging technology also directly affects the performance of the chip itself and the design and manufacture of the PCB (printed circuit board) connected to it.