Over a decade ago, wired connection and the dial-up internet to connect to the internet. Back then, wireless was a wild dream, and the fastest connection took hours. Broadband was for the rich with speeds of up to only 2-10 Mbps. Copper cable was the transmission medium. Communication over copper cable is the most used transmission medium but is currently facing competition from fiber optic cables.
Communication Over Copper Cable
Ethernet over copper is a transmission technology that use electrical pulses to transport data from the source to the destination. However, the electrical signal undergoes several interferences like:
- Electromagnetic interference- interference is caused by a disturbance generated by neighboring electrical equipment. The noise from the external source cause conduction, electromagnetic induction or electrostatic coupling on the copper wire. EMI is also referred to as Radio-frequency Interference (RFI).
- Crosstalk, it is the interference caused by magnetic fields due to a telecommunication signal from an adjacent cable affecting the signal in the adjacent circuit.
The above electrical disturbances corrupt the data signal, and the receiver gets a corrupted message. The signal on the copper cable also experiences attenuation. Attenuation loss is the loss of signal strength due to long distance transmission. Copper cable experience high attenuation and thus makes it unsuitable for long distance communication.
Communication Over Fiber Optic Cable
The fiber cable is constructed from glass fibers that transmit data packets in the form of light pulses. The source is a laser or an LED that emits light into the fiber cable. The core of the fiber, the glass, is like a mirror and the light pulses are reflected and refracted back and forth. The rays of light can bend at corners; therefore, the light reaches the receiver regardless of whether the pipe is straight. Fiber cables have low attenuation and do not experience electromagnetic interference or crosstalk.
When talking about the speed of a network, we are referring to the throughput of the network. Throughput is the amount of data that the infrastructure can transport per unit time. Fiber is said to be very fast that its speed compares to that of lightning. Others believe it is faster than lighting and hence the phrase “faster than lightning.” A copper network can, for example, carry 3,000 data bits at once while fiber network can carry 300,000 data bits at once or even more.
What makes the vast difference between the two networks? Fibers can carry high-frequency range than copper cables. The pulses of light are at a much higher frequency compared to electrical pulses. Hence the phrase “at the speed of light.” In a vacuum light can travel about 186,000 miles per second, it is incredibly fast. The speed leads to minimal loses and the data can move great distances.
The fiber networks also offer more bandwidth than copper cables. Though copper provides adequate bandwidth, fiber provides 1,000 times more bandwidth. A multimode fiber offers a bandwidth of 500MHz/km meaning 1 GHz for every 500 meters. Compare the value to a Cat 6 twisted pair copper cable, the fastest link on the market, which provides 500MHz for every 100 meters.
The fiber cable network may not transmit data at the speed of light but is just slightly lower. Due to the high speed, the photons in fiber cable can travel more distance at the same time than electrons in the copper cable. Therefore, unlike copper cables, fiber is not limited in terms of meters and the length can range from 10 km to 40km.
Optical cable reliability, fast speed, and long transmission distance are replacing the copper cables.