DEV Community: fubumingyu

Code With Heroines : TCP/IP && Rise and fall of the Han Dynasty

fubumingyu — Sun, 16 Jun 2024 14:34:08 +0000

Description

The dramatic fall of the Tang Dynasty within a collapsing virtual world. Zhu Quanzhong, depicted as a determined young girl with advanced hacking skills, leads the charge against a crumbling digital empire. The background is filled with fragmented data structures and corrupted files, symbolizing the breakdown of the system.

Tang Dynasty

Li Yuan founded the Tang Dynasty (618-907) after overthrowing the Sui Dynasty and establishing his rule in Chang'an. His successor, T'ai Zemin, solidified the dynasty's governance with a complex taxation system and a government structure based on the Ritsuryo system, which integrated military and agricultural duties. The central government operated through three ministries and six departments, focusing on criminal and administrative law.

Externally, the Tang Dynasty expanded its influence over neighboring regions, including the Tutsis, Western nations, tribes of the Northeast, and northern Vietnam, establishing local governorates. However, internal challenges arose, especially during the reign of Empress Noriten Wuhu (690-705), causing instability. Emperor Xuanzong (712-756) temporarily restored stability, but later reliance on Yang Guifei's family and local military chief Sodo-sha led to the An Lushan and Fumi Simyeong Rebellion (755-763).

Following the rebellion, the Tang Dynasty struggled with the dominance of local military chiefs, eunuch corruption, and external invasions. The weakening of the Ritsuryo system resulted in increased taxes, the collapse of the peasantry, and the rise of large noble estates. Military and taxation changes, including double taxation and monopolies on commodities like salt, further destabilized the dynasty. The late 9th century saw a major peasant uprising (875-884), and the Tang Dynasty ultimately fell to Zhu Quanzhong, an envoy to Tang China.

What is TCP/IP?

TCP manages the exact transfer of data, while IP determines the path along which data is sent. The following is a specific description of each role.

Roles of TCP

Simply put, it acts like a post office.

Data splitting and reassembly: Splits large data into smaller packets and reassembles them back to the original data at the receiving end.
Order control: packets are numbered and sent in sequence, then sorted in the correct order at the receiving end.
Error detection and correction: Checks whether packets were delivered correctly and requests retransmission if there is an error.
Connection establishment and termination: establishes a connection between the sender and receiver before sending data, and terminates the connection when the data transmission is finished.

Roles of IP

Simply put, it acts like a truck driver.

Addressing: Uses the source and destination IP addresses to determine where to send the data.
Routing: Ensures that data takes the optimal path from source to destination. This may involve going through multiple relay points.
Packet delivery: treats each packet individually and delivers it over the optimal route. Packets may take different routes.

Golang middleware && Wei, Jin, Southern and Southern Dynasties

fubumingyu — Wed, 05 Jun 2024 13:22:36 +0000

Explanation

The holographic projections symbolize the implementation of Golang middleware to transition and integrate new systems efficiently, reflecting Sima Yan's establishment of the Jin Dynasty.

Wei, Jin, Southern and Southern Dynasties

At the end of the Later Han Dynasty, Cao Pi (220-226), son of Cao Cao, established the Wei Dynasty (220-265) in northern China. Concurrently, Liu Bei (221-223) founded the Shu state (221-263) in Sichuan, and Sun Quan (229-252) established the Wu state (222-280) in Jiangnan, leading to the era of the Three Kingdoms. The Wei Dynasty eventually conquered Shu, and the Wei general Sima Yan (Emperor Wu, r. 265-290) overthrew Wei to establish the Jin Dynasty (265-316). The Jin Dynasty unified China in 280 but soon collapsed due to internal conflicts (the Eight Kings Rebellion, 290-306). During this time, the Xiongnu and other northern tribes gained strength. When the Xiongnu moved south, they destroyed the Jin Dynasty, leading to the chaotic period of the Wu Hu and Sixteen Kingdoms (304-439), characterized by intense warfare. The Jin family established the Eastern Jin Dynasty (317-420) in Jiangnan to resist these invasions. In the 5th century, the Northern Wei Dynasty (386-534), founded by the Tuoba clan, unified northern China, while the Rouran Khaganate opposed them on the Mongolian plateau. In the south, the Song Dynasty (420-479) succeeded the Eastern Jin. This era is known as the Northern and Southern Dynasties Period (439-589), marked by the rise and fall of five northern dynasties and four southern dynasties.

What is Golang middleware?

The term “middleware,” used when setting up an API server in Go, refers to the layer that processes HTTP requests along the way.
For example, it rewrites HTTP headers of the request, assigns a unique key to the request, outputs logs, and performs other processing that you may want to manage as a whole system, such as authentication.
authentication, and other processes that you want to manage as a whole system.

Reference

Code With Heroines : Availability && Redundancy && Fall of the Han Dynasty

fubumingyu — Tue, 04 Jun 2024 14:01:14 +0000

Explanation

This illustration demonstrates Availability by showing the abundance of goods and military presence.

Fall of the Han Dynasty

The Western Han Dynasty faced financial deterioration due to extensive foreign campaigns and increased taxes, which caused public hardship. Controversial policies like price stabilization and state monopolies on salt and iron were criticized. Following Emperor Wu's death, power struggles among bureaucrats, eunuchs, and maternal relatives, along with the rise of local clans, weakened the dynasty, leading to its fall to Wang Mang in 8 AD.

Wang Mang established the Xin Dynasty (8-23 AD) and attempted reforms based on the Zhou system, but these policies were unsuitable for the time, leading to increased chaos. The dynasty also faced famine and peasant rebellions, culminating in its collapse in 23 AD. Emperor Guangwu Liu Xiu then founded the Later Han Dynasty (25-220), restoring stability initially and expanding influence through conquests and foreign exchanges.

However, by the end of the 1st century, power struggles among maternal relatives, eunuchs, and bureaucrats resurfaced, causing political instability. The Yellow Turban Rebellion in 184 and the subsequent rise of warlords led to further chaos, resulting in the fall of the Later Han Dynasty in 220.

What is Availability?

Availability refers to uninterrupted access to information and the availability of data and systems when needed. Examples of such measures include 24/7 availability, data redundancy and replication, backup and restore, and load balancing for cloud services, etc.

What is Redundancy?

Prepare spare systems for servers and network systems in case of equipment failure or load caused by sudden access concentration. A spare system is operated in parallel to maintain functionality in the event of a system failure.
When a failure occurs in the main system, losses can be minimized by instantly switching to a backup system. In addition, in a cyber attack, natural disaster, or other emergency, business can be continued by switching to a spare system while minimizing damage. Redundancy is required today as the need for business continuity planning (BCP) increases.

Reference

Code With Heroines : SSL && Unification of China under the Han Dynasty

fubumingyu — Mon, 03 Jun 2024 12:45:03 +0000

Explanation

This represents the official discipline of Confucian studies introduced by Emperor Wu, emphasizing the importance of secure and reliable knowledge, much like how SSL ensures secure data transmission.

Unification of China under the Han Dynasty

The Han Dynasty was unified under the rule of Liu Bang (202-195 BC), the Han Dynasty's founder, instead of the Qin Dynasty.
Rather than implementing drastic reforms, Liu Bang combined the county and prefecture system with the feudal system, initially appointing lords from his family and meritorious vassals. However, family members soon replaced these lords, leading to the Wu-Chuzhou Rebellion in 154 BCE, which the government suppressed, consolidating its power. A centralized government was established during Emperor Wu's reign (141-87 BCE). Emperor Wu introduced a nomination-based system for appointing officials and made Confucian studies an official discipline. He pursued aggressive foreign policies, defeating the Xiongnu and expanding territory into northern Vietnam and the Korean peninsula. Despite an unsuccessful alliance with the Dajue clan in Central Asia, his efforts opened the way for managing the western regions.

What is SSL?

SSL (Secure Sockets Layer) is a mechanism for encrypting communications between the server that stores a website and the browser.
The most important reason for installing SSL is to protect the information of website users. Suppose personal details or credit card information is transmitted without encryption. In that case, there is a risk of being intercepted and misused, so SSL is necessary to ensure that users can use the website with peace of mind.
In addition, from the SEO perspective, there is a growing movement toward the introduction of SSL, and although it has been adopted as a ranking factor and warnings have been displayed for sites without SSL (non-https) for some time, from October 2023, “http” will be automatically changed to “https” on browsers such as Chrome HTTPS first mode was applied.
At first glance, SSL seems secure by itself when it is installed, but there are pitfalls.
As I mentioned, SSL is an encryption mechanism between the server and the browser; it does not guarantee the website's security that the user accesses. It is not uncommon to find phishing sites with SSL installed.

Reference

SSLとは？必要な理由を説明します