A communication line consisting of a plurality of mutually insulated conductors or conductors and having a sealed sheath outside. Some are also provided with an outer protective layer outside the sheath. There are many laying methods such as overhead, direct burial, pipeline and underwater. Divided into symmetrical, coaxial and integrated cables according to structure; It is divided into field and permanent cables (underground and submarine cables) according to functions. The transmission frequency band of the communication cable is wide, the communication capacity is large, and the external interference is small, but it is not easy to repair. It can transmit telephone, telegram, data and image, etc.

Communication cable (English name: communication cable) refers to the cable used for short distance audio communication and long distance high-frequency carrier and digital communication and signal transmission, and is one of the five major cable products in China. According to the purpose and scope of use of communication cables, it can be divided into six series of products, namely, urban communication cables (including paper insulated local telephone cables, polyolefin insulated polyolefin sheathed local telephone cables), long-distance symmetrical cables (including paper insulated high and low frequency long-distance symmetrical cables, copper core foam polyethylene high and low frequency long-distance symmetrical cables and digital transmission long-distance symmetrical cables) Coaxial cable (including small coaxial cable, medium coaxial cable and small coaxial cable), submarine cable (including symmetrical submarine cable and coaxial submarine cable), optical fiber cable (including traditional cable type, strip array type and skeleton type), and RF cable (including symmetrical RF and coaxial RF).