MindMap Gallery Information Technology and Development
This is a mind map about information technology and development, including computer software and hardware, computer networks, network standard protocols, fifth-generation communication technology, storage and databases, etc.
Edited at 2025-01-02 23:59:21Rumi: 10 dimensions of spiritual awakening. When you stop looking for yourself, you will find the entire universe because what you are looking for is also looking for you. Anything you do persevere every day can open a door to the depths of your spirit. In silence, I slipped into the secret realm, and I enjoyed everything to observe the magic around me, and didn't make any noise. Why do you like to crawl when you are born with wings? The soul has its own ears and can hear things that the mind cannot understand. Seek inward for the answer to everything, everything in the universe is in you. Lovers do not end up meeting somewhere, and there is no parting in this world. A wound is where light enters your heart.
Chronic heart failure is not just a problem of the speed of heart rate! It is caused by the decrease in myocardial contraction and diastolic function, which leads to insufficient cardiac output, which in turn causes congestion in the pulmonary circulation and congestion in the systemic circulation. From causes, inducement to compensation mechanisms, the pathophysiological processes of heart failure are complex and diverse. By controlling edema, reducing the heart's front and afterload, improving cardiac comfort function, and preventing and treating basic causes, we can effectively respond to this challenge. Only by understanding the mechanisms and clinical manifestations of heart failure and mastering prevention and treatment strategies can we better protect heart health.
Ischemia-reperfusion injury is a phenomenon that cellular function and metabolic disorders and structural damage will worsen after organs or tissues restore blood supply. Its main mechanisms include increased free radical generation, calcium overload, and the role of microvascular and leukocytes. The heart and brain are common damaged organs, manifested as changes in myocardial metabolism and ultrastructural changes, decreased cardiac function, etc. Prevention and control measures include removing free radicals, reducing calcium overload, improving metabolism and controlling reperfusion conditions, such as low sodium, low temperature, low pressure, etc. Understanding these mechanisms can help develop effective treatment options and alleviate ischemic injury.
Rumi: 10 dimensions of spiritual awakening. When you stop looking for yourself, you will find the entire universe because what you are looking for is also looking for you. Anything you do persevere every day can open a door to the depths of your spirit. In silence, I slipped into the secret realm, and I enjoyed everything to observe the magic around me, and didn't make any noise. Why do you like to crawl when you are born with wings? The soul has its own ears and can hear things that the mind cannot understand. Seek inward for the answer to everything, everything in the universe is in you. Lovers do not end up meeting somewhere, and there is no parting in this world. A wound is where light enters your heart.
Chronic heart failure is not just a problem of the speed of heart rate! It is caused by the decrease in myocardial contraction and diastolic function, which leads to insufficient cardiac output, which in turn causes congestion in the pulmonary circulation and congestion in the systemic circulation. From causes, inducement to compensation mechanisms, the pathophysiological processes of heart failure are complex and diverse. By controlling edema, reducing the heart's front and afterload, improving cardiac comfort function, and preventing and treating basic causes, we can effectively respond to this challenge. Only by understanding the mechanisms and clinical manifestations of heart failure and mastering prevention and treatment strategies can we better protect heart health.
Ischemia-reperfusion injury is a phenomenon that cellular function and metabolic disorders and structural damage will worsen after organs or tissues restore blood supply. Its main mechanisms include increased free radical generation, calcium overload, and the role of microvascular and leukocytes. The heart and brain are common damaged organs, manifested as changes in myocardial metabolism and ultrastructural changes, decreased cardiac function, etc. Prevention and control measures include removing free radicals, reducing calcium overload, improving metabolism and controlling reperfusion conditions, such as low sodium, low temperature, low pressure, etc. Understanding these mechanisms can help develop effective treatment options and alleviate ischemic injury.
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2.1.1 Computer software and hardware
hardware
Controller/Arithmetic (CPU), memory (memory is divided into: read and write RAM/ROM only) Input device, output device. Storage capacity is in bytes.
software
Programs and documents can be divided into system software, application software and middleware (between the operating system and application)
2.1.2 Computer Network
Communication basics
The communication system consists of three parts: source system, transmission system and destination system
Key technologies: digital communication technology, information transmission technology, communication network technology
Network Basics
Divided from the scope of network function: personal LAN, LAN, metropolitan area network, wide area network
From network users, they can be divided into: public network (for public use) and dedicated network (for units only)
Network equipment
Information transmission on the network mainly includes: Ethernet technology and network switching technology
Network switching forms: data exchange, line exchange, message exchange and packet switching
Different levels of exchange
Physical layer (telephone network); link layer (layer 2 switching, changing the MAC address); network layer (layer 3 switching, changing the IP address); transport layer (layer 4 switching, changing the port); application layer switching (Gateway)
Network interconnection devices: repeaters, bridges, routers, gateways and switches
OSI protocol
Physical layer
Including physical network media
RS-232, V.35, RJ-45, FDDI
Data link layer
Split data into specific frames
IEEE802.3/2, HDLC, PPP, ATM
Network layer
Network address translated into physical address, router
IP, ICMP, IGMP, IPX, ARP
Transport layer
Ensure data is reliable/error-free to transfer from point A to point B
TCP, UDP, SPX
Session layer
Establish and maintain communications
RPC, SQL, NFS
Expression layer
Act as a translator, format conversion
JPEG, ASCII, GIF, DES, MPEG
Application layer
Provide interfaces: HTTP, Telnet, FTP, SMTP
Wushu.com's report
Network Standard Protocol
Ethernet specification IEEE802.3 is an important LAN protocol
TCP and UCP
TCP
Reliable, connection-oriented; relatively small amount of data transmission and high reliability requirements
UCP
UDP is an unreliable, connectionless protocol.
Reliability requirements are not very high, but require fast speed occasions
Fifth generation communication technology
The fifth-generation communication technology 5G has the characteristics of high speed and low latency.
Application scenarios: Enhanced mobile broadband, ultra-high reliability and low latency communication and massive machine communication
2.1.3 Storage and database
Direct-connected storage (DAS)
The storage device is directly connected to the server through an optical cable (SCSI interface cable), and the I/O (input/output) request is directly sent to the storage device.
Network Format Storage (FAS)
Network access storage (NAS)
A professional network file storage and file backup device, based on TCP/IP LAN
Storage Area Network (SAN)
Confidentiality: Information is not disclosed to unauthorized individuals
Integrity: Protecting the correctness and integrity of assets
Connecting through fiber optics is costly
Storage Virtualization
One of the core technologies of cloud storage, improving resource utilization and improving running time
Green storage
The core is to design a processor with a lower temperature, which balances storage capacity, performance and energy consumption.
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1.2 Data Structure Model (Database core)
Three models
Hierarchical model
Use the "tree" structure to represent the association between entity sets
A node has multiple parent nodes, etc. It is clumsy to use hierarchical models to represent such connections (one-to-many connections)
Mesh model
Clearly represent this non-hierarchical relationship with mesh structure
There can be multiple parent nodes at more than two nodes; the structure is relatively complex and it is not easy for users to use.
Format structure pattern
Relational Model
A model that represents entities and connections between entities in the form of a two-dimensional table
1.3 Common database types
Relational Database (SQL)
ACID principles that support transactions, namely atomicity, consistency, isolation and persistence
Advantages: Easy to understand, easy to use, easy to maintain
shortcoming
Data reading and writing must be parsed by SQL, and large amounts of data and insufficient reading and writing performance
Has a fixed table structure, so it is difficult to scale, and the performance of multi-table association query is poor
Adopt a relational data model
Non-relational database (N0SQL)
Distributed, non-relational, and no guaranteed compliance with ACID principles
Common non-relational databases: key-value databases, column storage, document-oriented
advantage
High concurrency, strong reading and writing capabilities under big data; supports distributed and easy to expand; Simple, weakly structured storage
shortcoming
(1) Transaction support is weak, poor passability (2) No constraints, poor support for complex scenarios
1.4 Data Warehouse
Concept meaning
is a topic-oriented, integrated, nonvolatile and time-varying data collection used to support management decisions
Architecture
Data Source
Data sources are the basis of data warehouses
Data storage and management
It is the core of the database system. The real key to the data warehouse is data storage and management
Online processing analysis server
Online Extension Processing (OLAP)
Front-end tools
Query tools, report tools, analysis tools, data mining tools
Data analysis tools are mainly aimed at OLAP servers Reporting tools and data mining tools are mainly aimed at data warehouses
2.1.4 Information Security Basics
Information security level
Behavioral safety
Dynamic security
Requirements at the political, legal and moral levels
Behavioral safety
Dynamic security
Secrecy, integrity, controllability
Data security
Static security
Secrecy, integrity and usability
Equipment safety
Determinism, reliability, availability
Three elements of information security (CIA)
Confidentiality
Information is not disclosed to unauthorized individuals
Integrity
Protect the correctness and integrity of assets
test
Prevent modifications made by unauthorized subjects
Block the authorized subject from making unauthorized modifications
Make sure the data is not changed
Availability
Features that authorized entities can access and use when required
Chapter 2 Development of Information Technology
1.2 Encryption and decryption
Two elements of encryption technology: algorithm and key
Two types of data encryption technologies
Symmetric encryption
The encryption and decryption keys are the same
Data encryption standard: DES algorithm
Asymmetric encryption
The typical RSA algorithm is represented by the encryption key and the decryption key are different.
The encryption key is disclosed and the decryption key needs to be kept confidential
Digital signature
An information that proves the identity of the party and the authenticity of the data (third-party verification)
Digital signature and data encryption can be achieved simultaneously with RSA passwords
Certification
Identification/Confirmation: It is a process to confirm whether something is true or valid (both parties authenticate each other, and third parties are not allowed to verify it)
1.3 Information system security
Computer equipment security, network, operating system security, database system and application system security
1.4 Network Security Technology
Firewall
Establishing a filtering mechanism on the boundaries of internal and external networks, internal networks are considered secure and trustworthy, while external networks are considered unsafe and untrustworthy.
Intrusion detection and protection
Intrusion Detection System (IDS)
Pay attention to the supervision of network security status, violate security policies, and issue alarms. Most IDS systems are passive
Intrusion Protection System (IPS)
Provides active protection, controls intrusion behavior, and is to pre-intercept intrusion activities and offensive traffic.
Virtual Private Network VPN
Establish a dedicated and secure data communication channel in a public network Tunnel technology: point-to-point tunnel protocol, layer-2 tunnel protocol, IP security protocol
Security Scan
Scanners are one of the most effective network security detection tools to detect remote or host security weaknesses and system vulnerabilities.
Network honeypot technology
It is an active defense technology and a trap to "trap" attackers
User and entity behavior analysis technology
1.5Web Threat Protection Technology
Web access control technology
Username and password identification verification are required to access the web website
Single sign-on technology
Implement one-point login and multiple-point access
Web page tamper-proof technology
Including time polling technology, core embedded technology, event triggering technology File filtering driver technology
Web content security
It is divided into email filtering, web filtering, and anti-spyware
1.6 Safety behavior analysis technology
User and Application Entity Behavior Analysis (UEBA) provides user portraits and abnormal detection based on various analytical methods, combining basic analytical methods and advanced analytical methods.
UEBA systems usually include data acquisition layer, algorithm analysis layer and scenario application layer
Chapter 2 Development of Information Technology
2.1 Internet of Things
Key technologies
Key technologies mainly involve sensor technology, sensor network and application system architecture, etc.
Three-layer Internet of Things architecture
Perception layer
Various sensors are composed of temperature sensors, QR code tags, RFID tags and reader and writers, cameras, GPS and other perception terminals
Identify the source of objects and collect information.
Network layer
Various networks, including the Internet, radio and television network, network management system and cloud computing platform
The entire Internet of Things center is responsible for transmitting and processing information obtained by the perception layer.
Application layer
The application layer is the interface between the Internet of Things and users, which combines with industry needs to realize intelligent applications of the Internet of Things.
Application and development
2.2 Cloud computing
Cloud computing level
Infrastructure as a Service (IaaS)
Provide users with infrastructure services such as computer capabilities and storage space
Platform as a Service (PaaS)
Users provide platform services such as virtual operating systems, database management systems, and web applications.
Software as a Service (SaaS)
Provide application software (office software, etc.) to users, and provide multi-tenant, customizable application capabilities to users
Key technologies
Virtualization technology
Virtualization and hyperthreading are completely different. Multitasking refers to the running of multiple programs in one operating system at the same time; in virtualization technology, multiple operating systems can be run at the same time.
Hyperthreading technology only uses a single CPU to simulate dual CPUs to balance program running performance
Container technology
It is a new virtualization technology
Divide resources from a single operating system into orphan groups to better balance conflicting resource usage requirements among orphan groups
Cloud storage technology
A new storage form developed by traditional media (cloud)
Multi-tenant and access control management
Research on cloud computing access control model, cloud computing access control based on ABE password mechanism, multi-tenant in the cloud and virtualized access control
Cloud security technology
Cloud computing security, to ensure the security of cloud infrastructure, cloud security technology services
2.3 Big Data
feature
Massive data, diverse data types, low data value density, fast data processing speed, etc.
Key technologies
Big data acquisition technology
The research focuses on data acquisition, integration and cleaning
Distributed data processing technology
Distributed computing systems include Hadoop, Spark and Storm
Big data management technology
Mainly focused on big data storage, big data collaboration, security and privacy
Big data application and service technology
Mainly includes analytical application technology and visualization technology
Chapter 2 Development of Information Technology
2.4 Blockchain
Technical Basics
Based on asymmetric encryption algorithm, the improved Merkle Tree is used as a data structure, and a distributed storage database technology is composed of consensus mechanisms, point-to-point networks, smart contracts and other technologies.
It is divided into: public chain, alliance chain, private chain and hybrid chain
It has the following characteristics: multi-centralization, multi-party maintenance, time-series data, smart contracts, and tamper-free
Key technologies
(1) Distributed ledger (2) Encryption algorithm (3) Consensus mechanism
Application and development
2.5 Artificial Intelligence
Machine Learning
It is a technology that automatically matches the model with data and “learns” the data by training the model.
Neural networks are a form of machine learning
Machine learning models are statistics-based.
Natural Language Processing
Committed to research various theories and methods for achieving effective communication between humans and computers using natural language
It should be applied to machine translation, public opinion monitoring, automatic summary, opinion extraction, text classification, question answering, text semantic comparison, speech recognition, Chinese OCR, etc.
Expert system
2.6 Virtual Reality
Technical Basics
Virtual reality technology has been used to start from desktop virtual reality systems, immersive virtual reality systems, and distributed virtual reality systems.
feature
Immersiveness
Users become and feel that they are part of the environment created by computer systems
Interactive
The user's degree of operability to objects in the simulated environment and the natural degree of feedback from the environment.
Multi-perception
It means that computer technology should have many ways of perception
Conceptual
Also known as imagination, users can interact with surrounding objects in virtual space.
Autonomy
Autonomy refers to the degree to which objects in a virtual environment act according to the laws of physics.
Key technologies
Mainly involved in human-computer interaction technology, sensor technology, dynamic environment modeling technology and system integration technology
Application and development
The current technological trends and directions mainly focus on the following aspects: (1) The iteration of hardware performance optimization and iteration accelerates (2) The degree to which the development of network technology effectively helps its application. (3) The virtual reality industry elements are accelerating integration (4) New technologies drive new business