Copper core wire is inside the cable; The inside of the cable is glass fiber. A cable is usually a rope like cable that is twisted by at least two conductors in each group. The optical cable is a communication line that a certain number of optical fibers form the cable core in a certain way, which is wrapped with a sheath, and some are also covered with an outer sheath to realize optical signal transmission.

When the voice signal is converted into an electrical signal by the telephone, it is transmitted to the switch through the line, and then the switch directly transmits the electrical signal through the line to another telephone to answer the call. The transmission line in this call process is the cable.

When the voice signal is converted into an electrical signal by the telephone, it is transmitted to the switch through the line, and then the switch transmits the electrical signal to the photoelectric conversion equipment (converts the electrical signal into an optical signal) through the line to another photoelectric conversion equipment (converts the optical signal into an electrical signal), and then to the switching equipment to answer the call on another telephone. The line between the two photoelectric conversion devices is the optical cable.

Copper core wires are mainly used in cables. The diameter of core wire can be 0.32mm, 0.4mm and 0.5mm. The larger the diameter is, the stronger the communication capability is; There are also 5 pairs, 10 pairs, 20 pairs, 50 pairs, 100 pairs, 200 pairs, etc. according to the number of cores. Optical cables can only be divided into 4, 6, 8, 12 pairs of cores.

Cable: It has large volume and weight, poor communication ability, and can only be used for short distance communication. Optical cable: It has the advantages of small volume, weight, low cost, large communication capacity, strong communication ability, etc. Due to many factors, it is only used for long-distance and point to point (i.e. two switching rooms) communication transmission.

In fact, the differences between cable and optical cable are mainly shown in three aspects.

First, there are differences in materials. The cable is made of metal (mostly copper and aluminum) as the conductor; The optical cable uses glass fiber as the transmission conductor.

Second, there are differences in transmission signals. Cables transmit electrical signals. Optical cables transmit optical signals.

Third, there are differences in the scope of application. Cables are now mostly used for energy transmission and low-end data information transmission (such as telephone). Optical cables are mostly used for data transmission.

It can be known in practical application that optical fiber cable has a larger transmission capacity than copper cable, with long distance, small volume, light weight and no electromagnetic interference in the trunk section. It has developed into a backbone of wired transmission lines for long-distance trunk lines, urban trunk lines, offshore and trans ocean undersea communications, as well as local area networks, private networks, etc., and has begun to develop into the field of urban user loop distribution networks, which is called fiber to the home Broadband integrated services digital network provides transmission lines.