Introduction to Computer Networks | What is LAN?

Introduction to Computer Networks | What is LAN?

As a first step on our path to CCNA certification we will touch on the topic of CCNA 1, Introduction to Computer Networks or what is LAN?
n this section we will be dealing with one of the first issues for CCNA certification called Network Fundamentals or Network Fundamentals. In today's world, we are connected as never before thanks to the use of networks, and that is how we perceive it in the news and discoveries that are known throughout the world in a matter of seconds, or, people who play with friends who are on the other side of the ocean and on other continents.

1. NETWORKS AND NEW FORMS OF COMMUNICATION

Internet globalization leads to new forms of communication that provide the ability to create information that can be accessed by a worldwide audience.

Some forms of communication you already know include the following:

• Text : allows two or more people to communicate instantly and in real time.
• Social media : they consist of interactive websites in which people and communities create and share user-generated content with friends, family, and the rest of the world.
• Collaboration tools : they allow people to communicate with each other, usually through real-time interactive video, without location or time zone limitations.
• Blogs : it is an abbreviation of the word weblogs and they are easy to update and edit web pages (such as  GNS3 Blog ).
• Wikis : these are web pages that user groups can edit and view together. While a blog is more like an individual and personal diary, a wiki is a group creation. As such, it may be subject to more extensive review and editing. (Example, Wikipedia)
• Podcasting : allows people to spread their audio recordings to a vast audience. The audio file is placed on a website (or blog or wiki) where others can download and play it on their PCs or other mobile devices.
• Peer-to-peer file sharing application (P2P): allows people to share files with each other without having to store them on a central server or download them from such a server. To join the P2P network, the user must simply install a P2P software.

What other sites or tools do you use to share what you think?

2. TYPES OF NETWORKS ACCORDING TO THEIR SIZE

There are networks of all sizes. They can range from simple networks, consisting of two PCs, to networks that connect millions of devices. Let's see some images to know more about the different sizes of networks.

• Small Networks : Small domestic networks connect some computers to each other and to the Internet. They are simple networks that are installed in homes allow you to share resources, such as printers, documents, images and music, between some local PCs.
• Office Networks (Home Offices) : Considered as medium sized networks, they allow computers in a home office or a remote office to connect to a corporate network and have access to centralized shared resources.
• Medium to Large Networks: Medium to large networks, such as those used in corporations and schools, can have many locations with hundreds or thousands of interconnected computers.
• World Networks : The Internet is a network of networks that connects hundreds of millions of computers worldwide. Internet is the most extensive network that exists. In fact, the term Internet means "network of networks." The Internet is literally a collection of interconnected private and public networks.

3. Clients & Servers in Computer network

In every computer network there are clients and servers. What does each of them mean and why is it important in computer networks? Let's also see what types of clients and servers exist.

All PCs connected to a network that participate directly in network communications are classified as hosts. The hosts are also called terminals.

WHAT IS A SERVER

The servers are PCs with software that allows them to provide information, for example email or web pages, to other terminals in the network. Each service requires a separate server software. For example, to provide web services to the network, a server needs a web server software. A PC with server software can provide services to one or more clients simultaneously. In addition, a single PC can run several types of server software.

TYPES OF SERVERS

1. File Server : The file server stores user and / or business files in a central location.
2. Web Server : The web server runs web server software and contains web pages.
3. Email Server : The email server runs email server software

WHAT IS A Clients?

Clients are PCs that have software installed that allows them to request information from the server and display the information obtained. A web browser, such as Chrome or Firefox, is an example of client software. A single PC can also run several types of client software. For example, a user can check their email and view a web page while using the instant messaging service and listen to the radio over the Internet.

TYPES OF CLIENT

• File Client : Client devices have access to these files through client software, such as Windows Explorer.
• Web Client : Customers use their browser software, such as Chrome, Opera or Firefox, to access the web pages found on the server.
• Email Client : Customers use their email client software, such as Microsoft Outlook, to access email messages found on the server.

4. PEER NETWORK (P2P)

Server and client software usually run on different computers, but it is also possible for the same computer to perform both functions at the same time. In small businesses and homes, many PCs function as servers and clients on the network. This type of network is called a peer network .

WHAT ARE P2P NETWORKS

P2P (Peer to Peer) or Peer-to-Peer networks are PCs that function as servers and clients on the network. A P2P network is made up of personal computers, each of which acts as a client and server, so that each one can exchange files directly with any other computer on the network. Each computer can access any of the others, although access can be restricted to those files that the user of a computer decides to make available. A Peer to Peer network is less expensive than client / server networks but less efficient when large amounts of data must be exchanged.

CHARACTERISTICS OF PEER NETWORKS

To determine what type, P2P or client / server, the network architecture to configure and use, you must consider:

• The type of user and the size of the organization.
• The peer-to-peer network is used in homes and small businesses because its implementation is economical and the user is the administrator.
• The client / server network is ideal for large corporations, schools and hospitals due to the large number of users and workstations it can accommodate, but it is more expensive than the point-to-point network.

THE ADVANTAGES OF PEER NETWORKS

The advantages of peer networks are presented below:

• Simple setup
• Less complexity
• Lower cost, since network devices or dedicated servers may not be required
• They can be used for simple tasks such as transferring files and sharing printers

THE DISADVANTAGES OF PEER NETWORKS

The disadvantages of peer networks are presented below:

1. Decentralized administration
2. They are not so safe
3. They are not scalable
4. All devices can function as clients and servers, which can slow performance

See you in a next post!