Seven types of lines are proposed for the following reasons:

1. Compared with optical fiber LAN, the solutions of seven types of systems provide the required performance and bandwidth, but their overall cost is only a fraction of that of optical fiber.

2. Optical fiber system can bring enough bandwidth to people, and the price of optical fiber cable is close to seven types of cables. However, if the cost factors of optical fiber routers, optical switches and optical network cards are taken into account, the price advantage of optical fiber will soon be lost.

The cost of optical communication network has been greatly reduced before Category 7 lines can show real advantages in the above two aspects, and because of the natural advantages of optical communication in transmission distance, Category 6 lines have been completely suppressed by optical communication before they can develop rapidly.

Now, "light enters copper and retreats" is not only the slogan of communication operators, but also a solid step. FTTx and PON technologies have been widely used in the field of communication network access. Local area network communication is about to stage a scene of "light enters copper and retreats".