"Please contact in advance if there is a national defense optical cable construction". Can anyone give a specific explanation on "national defense optical cable"? detailed

It is an optical cable laid to meet the information communication between the army and the country, mainly serving the national defense communication network. The characteristics of the national defense communication network are as follows: First, the contact is very extensive. The relationship between national defense and politics, economy, domestic social activities and diplomacy is completed by communication, and the internal activities of national defense construction are also completed by communication. Second, the communication industry does not produce physical products. Its products show the spatial transfer of information and mail, and its production process and consumption process are basically the same; Third, national defense communication must ensure that information is transmitted to the destination quickly, timely, accurately and safely. Especially, communication in the army is the basic means to ensure operational command, which can make the orders and instructions of superiors be issued in time, and the situation of subordinates be reported in time to ensure close coordination between friendly and neighboring troops. In the modern national defense construction, all construction undertakings and military activities can not be separated from the exchange and transmission of information for a moment, and all major decisions can only be made on the basis of obtaining a large amount of information. With the application of high-tech in the military field, military operations need extensive cooperation, such as cooperation between services and arms, cooperation between the army and political, diplomatic, economic and cultural propaganda, cooperation between the army and policies, and so on, which can only be realized through communication. The construction of national defense communication network is an important part of national defense construction and the basic condition to ensure the smooth completion of training operations and combat tasks.