1. Introduction to Computers
Introduction to Networking

2. Networking and Vocabulary
We all use networks every day of our lives, and thus have an intuitive understanding of what a network is, and how it is used. However, for the purposes of education and administration it is important to define networking terms and break down a network into composite parts
Network - A network is a group of interconnected computers and other devices that are able to share information with each other
Nodes/Hosts - Computers and devices that have a need to communicate with each other. For our purpose, these terms are synonyms
Connecting Media - This is the physical connection between nodes/hosts. It can be twisted pair cabling, fiber optic cables, or even WiFi radio signals

3. Networking and More Vocabulary
Network Interface - This is the port and hardware element that connects the computer or other device to the network. It converts the digital data that's coming from the computer into some type of signal that can be transmitted on the network medium
Network Protocol - These are the standards that define how data going along the network medium is going to be formatted. The important thing to remember is the fact that if the computers on the network aren't using the same network protocol, then they're not going to be able to understand the data that's being communicated

4. Benefits of Networking - Sharing Peripherals
Networks can be very expensive to set up, and even more expensive to maintain, so why would a company go through with this expense? Networks offer huge advantages to devices
Sharing peripherals - First of all a company can save money by sharing common use peripherals. For example, let’s say a company needs to print and scan documents often. If every employee had a printer, even if the office as a whole printed often, each individual printer would be idle most of the time. The company would be wasting money buying so many printers, but a few times a day each employee will need access to a printer. We can set up a network to have one printer per floor, and share the resource amongst the employees

5. Benefits of Networking - Consolidate Storage
Once we have a network setup, we can consolidate storage and store our data at a convenient centralized point. This gives us a lot of benefits
Cost - Each computer can have less storage locally since they store data on a network device
Mobility - We can move computers and users around without worrying about access to data. Users can be moved from one computer to another and still access all of their files, so long as their new computer is still connected to the network
Security - Since all data is stored at one central point instead of spread throughout multiple computers it is easier for a network administrator to protect and maintain the data. Access can be monitored and controlled more easily, and backups are easier since there is only one device to backup

6. Benefits of Networking - Collaboration/Communication
Employees can use a network to share information and work. For example, if we are working on a multimedia project (a game, movie or report for example) each person contributing to the whole can add their work to a project folder and have a team leader assemble the parts into a whole. Or team members can share resources and research on a common goal
Companies can also provide resources to customers through a network. For example, companies can provide a website to allow customers to research their products, use social media to communicate to customers, provide a store for customers to purchase products and provide a forum for users to communicate. A strong internet presence is essential to a modern company

7. Network Types Peer to Peer
We can categorize networks into two basic types based on the roles and responsibilities of hosts
In a peer to peer network, all nodes are equal. They will both provide and consume network services
This means that for example, one host could be connected to a printer that it shares, and another computer could be connected to an external hard drive that provides the network with storage space. The printer computer can use the storage space, and the storage computer can use the printer

8. Advantages and Disadvantages of Peer to Peer Networks
Peer to Peer network advantages
It is simple to set up
Doesn’t require specialized software or much hardware
Tends to be inexpensive
Peer to Peer network disadvantages
Not scalable. Handles smaller networks fine, but larger networks become unwieldy
Support is hard, since there is no centralized location for administration. For example, we may have multiple users who decide to share some local storage space over the network to make collaboration easier. To properly backup the data at this point, we’ll need to go to each sharing computer and back them up
Too much authority is in the hands of the local users. Users could go in and delete files from shared storage, turn off computers that are sharing devices like printers, or make other changes locally that will remove resources from the network

9. Network Types Client/Server
Unlike a peer to peer network, each host in a client/server network has a specific role
Servers provide resources
Clients consume resources
This means that all network available resources will be on servers and users will be on clients
This also means we’ll need different operating systems for the clients and servers
The client operating system has to be something that will allow the user to perform their daily tasks and access the server’s resources, while the server’s operating system has to be designed to offer the resources to clients

10. Advantages/Disadvantages of Client/Server Networks
Client/Server Advantages
Very scalable; Relatively easy to add servers and clients to expand the network
Easier to support since hosts are locked into roles. If you have an issue with the printer, you know there is a centralized printer server that has an issue, and you don’t need to take a user off of their machine
Networked data is centralized, so it is easier to keep secure, backup and otherwise manage
Client/Server Disadvantages
More expensive to implement and maintain than peer to peer because it requires specialized hardware, software and training
Takes more planning than peer to peer, since you have to plan out number of servers and what services they provide, compared to just adding services to peers