The measure of fiber capacity and transmission speed is usually noted in which unit?

The correct unit to measure fiber capacity and transmission speed is gigahertz (GHz). This measurement indicates the frequency of the signal being transmitted over the fiber optic cables. Higher frequencies typically allow for higher data transmission speeds and increased bandwidth, which are critical for modern communication systems that handle large amounts of data.

When assessing data capacity and transmission speed in fiber optics, understanding the role of frequency is important. Signals transmitted at higher frequencies can carry more data within the same time frame compared to lower frequency signals. This capability is essential for applications requiring high-speed internet and large-scale data transfers.

Other units mentioned have different purposes: nanometers (nm) are used to measure wavelengths of light and not directly related to speed; decibels (dB) measure signal loss or gain, not capacity or speed; and kilometers (km) measure distance rather than transmission characteristics. Understanding these distinctions helps clarify why gigahertz is the appropriate choice for measuring fiber capacity and transmission speed.