Today we will start talk about the concept of a network. This will help providw a background in networks and network types. Understanding how networks communicate is very important.

 Let’s take you back to the internet. 

The internet is a worldwide collection of interconnected networks, cooperating with each other to exchange information using common standards.

If you didn’t know anything about the internet, now you do. The internet has become a major part of everyday life. So much that it is the norm because everything that you access online is located somewhere on the global internet.

 

Data Transmission

Computers and networks only work with binary digits, zeros, and ones. A bit is stored and transmitted as one of two possible discrete states. Computers use binary codes to represent and interpret letters, numbers, and special characters with bits. When you have a group of eight bits, this is known as a byte.

 Bits and Bytes really grind my gears lol I had to throw that in there. But no seriously, I still have trouble understanding BINARY. 

 

Every input device (mouse, keyboard, voice-activated receiver) will translate human interaction into binary code for the CPU to process and store. Every output device (printer, speakers, monitors, etc.) will take binary data and translate it back into human recognizable form. Within the computer itself, all data is processed and stored as binary.

 

After the data is transformed into a series of bits, it must be converted into signals that can be sent across the network media to its destination. Media refers to the physical medium on which the signals are transmitted. Examples of media are copper wire, fiber-optic cable, and electromagnetic waves through the air. A signal consists of electrical or optical patterns that are transmitted from one connected device to another. These patterns represent the digital bits (i.e. the data) and travel across the media from source to destination as either a series of pulses of electricity, pulses of light, or radio waves. Signals may be converted many times before ultimately reaching the destination, as corresponding media changes between source and destination.

There are three common methods of signal transmission used in networks: 

  • Electrical signals - Transmission is achieved by representing data as electrical pulses on copper wire.

  • Optical signals - Transmission is achieved by converting the electrical signals into light pulses.

  • Wireless signals - Transmission is achieved by using infrared, microwave, or radio waves through the air.

 

Bandwidth and Throughput

The rate of data transfer is discussed in terms of bandwidth and throughput

Bandwidth is the capacity of a medium to carry data. In order words the capacity of a network communications link to transmit the maximun amount of data it can from one point to another over a network connection.

 An example of this can be streaming a movie. If you want your movie to stream smoothly (high bandwidth) networks have to be capable of transmitting and receiving bits at a very high rate.

Throughput is the measure of the transfer of bits across the media over a given period of time.

Many factors influence throughput including: 

  • The amount of data being sent and received over the connection

  • The types of data being transmitted

  • The latency created by the number of network devices encountered between source and destination

 

Network

Is a system of computers and other devices that are connected together via cabling or wirelessly for the purpose of sharing resources, data, and applications.

Clients and Server Roles

A host is computers connected to a network that sends and receives messages on the network. A computer can act as a server or a client or even both. Servers are hosts that have software installed that enables them to provide information such as email or web pages.

 Email server runs on email server software

Web server runs on webserver software

File server stores corporate and user files in a central location

 

Peer-to-peer Networks

  • When you have a computer that functions as the server and client on a network that is called a peer-to-peer (P2P) network.

  • Sometimes called workgroups.

  • No centralized management or security and each computer is in charge of its own local users and file and folder permissions.

  • Usually connected together through a simple hub or network switch.

  • Usually works good with home networks or small office networks since there aren’t a lot of users and computers to manage. 

Network Infrastructure

A network infrastructure contains three categories of hardware components.

  • End devices that can consist of your laptop, phone, & printer.

  • Intermediary devices such as a wireless router, LAN Switch, & Router.

  • Network Media such as wireless Media, LAN Media, & WAN Media.

 

I know sometimes the basics aren’t as juicy but hey you have to start somewhere. Since I’m new to the field, I have no choice but to take it back to the basics. Don’t worry I will get to the cool stuff after we have built a solid foundation. The information in the blog is based on the course I’m taking from CISCO called Networking Essentials.

 

Hope you all enjoyed it! Let me know what you think!

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