Chapter 8

In this article Chapter 8 of CISCO "Network Fundamentals" tackles about the importance and function of the first layer of OSI model which is the Physical layer. Physical layer works by transporting bits of information frame across the local media that follows the physical layer fundamental principle in the core of the process after the encoding of bits in signaling, physical layer happens. furthermore signal vary in the medium by its frequency, amplitude, phase and clock rate  . media we have different types that help lot to the success of transporting data some of this media is copper wires, UTP (Unshielded twisted pair), Coaxial cable wires. this are the common media sited in the chapter 8 article. of course different media means different performance. the physical layer happens in the hardware by its standard sets IEEE, ISO, ANSI etc.an electrical signal will be transmitted on the media(Copper wire), a microwave signal in wireless device and light impulse in fiber optic. This where throughput, bandwidth and goodput be seen. throughput means the actual performance of  the actual data transfer while the bandwidth is the amount of data that can be carried from source to destination  while the goodput is the application of throughput. of course if we have media we must also have a connectors inb the article sited some of the connectors these are: 110 punch block, RJ45 socket/plug. this is what chapter tackles all about to how physical layer function to the devices needed to success the delivery of the data and here are some important key word to remember:

1. Physical layer - The Physical Layer consists of the basic hardware transmission technologies of a network. It is a fundamental layer underlying the logical data structures of the higher level functions in a network.
2. Network Media - (sometimes referred to as networked media) refers to media mainly used in computer networks such as the internet.
3. Throughput -  means the actual performance of  the actual data transfer
4. Media - A media connector attaches to the transmission media and allows the physical connection into the computing devices.
5. Data Signal - A pulse or frequency of electricity or light that represents data as it travels over a network, a computer channel or wireless.