[Supplement to the new version of the system architecture] - seven-layer model

Network Functions and Classifications

Computing network functions: data communication, resource sharing, centralized management, distributed processing, load balancing
Network performance indicators: speed, bandwidth (bandwidth or transmission line rate), throughput, delay, round-trip time, utilization
network Non-performance metrics: cost, quality, standardization, reliability, scalability, upgradeability, manageability, and maintainability

Bus type (low utilization rate, large interference, low price)
star type (local area network formed by switches, large central unit load)
ring type (fixed flow direction, low efficiency and difficult to expand)
tree type (bus type expansion, hierarchical structure)
distribution (any node connection, difficult management and high cost)

communication technology

Signal processing performed by the transmitter includes source coding, channel coding, interleaving, pulse shaping and modulation.
Multiplexing technology and multiple access technology are required if multiple channels of data are transmitted at the same time

OSI seven-layer model

LAN and WAN protocols

Ethernet specification IEEE 802.3 is an important LAN protocol, including
IEEE 802.3 standard Ethernet 10Mb/s transmission medium is thin coaxial cable
IEEE 802.3u Fast Ethernet 100Mb/s twisted pair
IEEE 802.3z Gigabit Ethernet 1000Mb/s optical fiber Or twisted pair
IEEE 802.3ae 10 Gigabit Ethernet 10Gb/s optical fiber

Wireless local area network WLAN technical standard: IEEE 802.11

TCP/IP protocol

routing technology

Routing functions are provided by routers and include:

1. Heterogeneous internetworking, such as internetworking with heterogeneous subnet protocols
2. Subnet protocol conversion, protocol conversion between different subnets including LAN and WAN
3. Data routing, that is, forwarding data from one network to another network according to routing rules
4. Rate adaptation, using caching and flow control protocols for adaptation
5. Isolate the network, prevent broadcast storms, and implement firewalls
6. Fragmentation and reassembly of packets, packets exceeding the MTU of the interface are fragmented, and packets arriving at the destination are reassembled
7. Backup, flow control, such as switching of main and backup lines and complex flow control, etc.

Routing protocols are divided into: Interior Gateway Protocol (IGP), Exterior Gateway Protocol (EGP)

Network construction projects are divided into: network planning, network design, network implementation

Soft test-system architect knowledge points extraction-system architect tutorial (2nd edition)

1. Chapter One Introduction
2. Chapter 2 - Basic knowledge of computer systems (1)
3. Chapter 2 - Basic knowledge of computer systems (2)
4. Chapter 3 - Basic knowledge of information systems
5. Chapter 4 - Basic Knowledge of Information Security Technology
6. Chapter 5 - Basic knowledge of software engineering (1)
7. Chapter 5 - Basic knowledge of software engineering (requirements engineering and system analysis and design)
8. Chapter 5 - Basic knowledge of software engineering (software testing, clean room software engineering, component-based software engineering, software project management)
9. Chapter 6 - Basic knowledge of database design (basic concepts of database, relational database)
10. Chapter 6 - Database Design Basics (Database Design)
11. Chapter 7 - Basic knowledge of system architecture design (architecture-based software development method)
12. Chapter 7 - Basic knowledge of system architecture design (architecture style, reuse)
13. Chapter 8 - System Quality Attributes and Architecture Evaluation
14. Chapter 9 - Software Reliability Fundamentals
15. Chapter 10 - Evolution and Maintenance of Software Architecture
16. Chapter Eleven - Future Information Technology
17. Chapter 12 - Information System Architecture Design Theory and Practice
18. Chapter 13 - Hierarchical Architecture Design Theory and Practice
19. Chapter Fourteen - Cloud Native Architecture Design Theory and Practice
20. Chapter 15 - Service-Oriented Architecture Design Theory and Practice
21. Chapter 16 - Embedded System Architecture Design Theory and Practice
22. Chapter 17 - Communication System Architecture Design Theory and Practice
23. Chapter 18 - Security Architecture Design Theory and Practice
24. Chapter 19 - Big Data Architecture Design Theory and Practice
25. [Supplement to the new version of the system architecture] - Embedded Technology
26. [Supplement to the new system architecture] - Embedded software