The Great Wall has different names for this kind of defense works, such as Liecheng, Fangcheng, Fortress, Linluo, Jiegou, Side Wall and so on. In fact, they all refer to the Great Wall. In fact, the Great Wall in a broad sense refers to all the giant military engineering systems in ancient China.
Huo Feng communication
As early as the Zhou Dynasty, China had a method of transmitting information by bonfire. As a primitive means of acousto-optic communication, bonfire served the ancient military war. From the border to the capital and the border, a beacon tower is built at regular intervals. When the enemy invaded, firewood was stored inside, and the fire alarms were lit one by one. When the princes saw the fire, they immediately sent troops to help and resist the enemy.
During the Western Zhou Dynasty, in order to guard against enemy invasion, the "bonfire tunnel" was used as the contact signal for border defense emergency. On the passage from the frontier to the hinterland of various countries, a beacon tower is built at intervals, one after another. There are oranges on the stage, and there are cages full of firewood on the heads of oranges. When the enemy invaded, the beacon tower set off fireworks in succession to convey the alarm. Every night, the watchman lit the firewood in the cage and held it high, calling it a "lighthouse" to convey information to the leaders. During the daytime warning, the firewood piled up on the stage is lit, and the smoke is used to indicate the urgency, which is called "embarrassment". In order to make the smoke straight without bending, so that it can be seen from a distance, the ancients often used wolf dung instead of firewood, so it was also called wolf smoke. The Zhou Dynasty stipulated that when the emperor raised a bonfire, local governors must immediately lead troops to rescue and fight against the enemy. It can be seen that the implementation of the beacon system means that a huge and perfect military information contact network has appeared as early as last week.
Banner newspaper, brand newspaper, and post-unveiling banner newspaper originated from "unveiling cloth" in ancient China. They are usually carried by special personnel, rode on horses, and sent out by Mercedes-Benz for military and civilian reading along the way to boost morale. Brand newspaper is a news dissemination tool written on "raft", while posters are printed materials similar to leaflets, which can be distributed everywhere.
Newspapers began in the Qing Dynasty, mainly concentrated in Beijing. As early as the early Qing Dynasty, there were people engaged in newspaper copying activities in private names in Beijing, mostly low-level officials, who took printing and newspaper copying as a sideline. By the middle and late Qing Dynasty, it had evolved into a private newspaper.
On behalf of all official documents and letters, the organization is always called "delivery" and has "emergency delivery shop" with a copper bell tied to the horse's collar in a hurry. Running on the road, ringing the bell during the day and lighting a fire at night, the person killed is not responsible. Shopping for horses, shopping for people, rain or shine, day and night. In the early years of Southern Song Dynasty, Yue Fei, an anti-gold general, was forcibly recalled to Lin 'an from the front with 12 gold medals by Song Gaozong. This kind of gold medal is a gold plate sent by express delivery, indicating urgency.
In ancient times. People build tall beacon towers. When the enemy invaded, they immediately lit the firewood on the beacon tower, transmitted the enemy's message with the burning beacon smoke, and called the army to come to help. Later, people found a way to send information by horse. Many post offices have been set up all over the country, and special people deliver letters. In this way, information can be transmitted to far places by horses. Later, people invented the method of transmitting information by semaphore and light.
A whole set of evacuation system was formed in Qin and Han Dynasties. Especially in the Han Dynasty, the documents delivered were graded, and the documents of different grades should be delivered by special personnel and special horses in accordance with the prescribed order and time. Sending and receiving these documents must be registered and marked with time to show responsibility.
During the Sui and Tang Dynasties, the cause of evacuation developed unprecedentedly. The official postal transport line in the Tang Dynasty centered on Chang 'an, the capital city, radiating in all directions and reaching the frontier, with a post station about 30 miles away.
The transmission of information on the Internet is similar to the transmission of letters:
First, in the Internet, when information chooses a path, it is not fixed. In other words, whenever information is to be forwarded to a certain place, the network will choose the optimal path according to the situation at that time to achieve the purpose of fast transmission.
Second, when you want to transmit a file, especially a large file, the Internet does not transmit the whole file together, but first divides it into smaller information blocks, and each block is marked with the address of the sender and the receiver, and then transmits each block separately. Because each packet of the file is transmitted separately, different paths can be adopted. After all the data packets arrive at the destination, they are rearranged, sorted and merged according to the transmission control protocol, and the original files are restored and then handed over to the users.