The History Of The Network Essentials

Published Date: 02 Nov 2017

NETWORK ESSENTIALS

Computer network is a group of computer systems and the other computer hardware devices is connected together through communication channels. Networks are basically categorized on their characteristics.

In question one, they asked to find two types of computer networks that are wired network and wireless network.

Wired network is classified as the traditional choice in homes, however wireless network (Wi-Fi) are gaining ground so fast.

Both wired network and wireless network have their own ways to protect from computer virus and hackers.

QUESTION 1

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Wired Network

Wired Network provides users with lots of of security and the ability to move lots of data quickly. Compared to wireless network, wired network is typically faster than it. However, the cost of Ethernet cable will expensive by adding more computers on the network itself, and the more expensive the network will be.

Moreover, unless you are builds a new house and installing Ethernet cable inside the walls, you will be able to see the cables running from a place to another place around your home, and also the wires can greatly limit into your mobility. For example, a laptop owner would not be able to reduce or move around easily if his or her computer is tethered to the wall.

There are three basic systems people use to set up wired networks. An Ethernet system uses a twisted copper pair or coaxial based on transport system. Mostly common used cable will be Ethernet is a category under unshielded twisted pair(UTP) cable. Normally this type of cable useful for the large businesses who want to connect several devices together such as printers and so on but it’s very expensive.

First of all, should keep it separatedly. It means the user must keep their own computer work and do their email and personal web browsing on a different computer system. This will protect their working environment. It will also keep your personal files of a system that may belong to their employer. If they changing job, they do not need to transfer all of their personal information over.

Second, keep it clean. It means, the user must often cleaning their desks not only for make it easier to stay focused on work, but to ensure that sensitive information is not accidentally read by a neighbour, cleaner, carpenter, babysitter or any other person who actually does not need to know it. User can buy a lockable filing cabinet, and lock the screen of their work computer when it is not in use. The same goes for working while at a cafe hotel or other public place. Always bare mind that to save any personal documents and keep them safe from wandering eyes.

Third, install security software on all home and personally owned computers. This statement tells, the user should be installed anti-virus and personal firewall software on all computers in their home or public network. Notice that this software should be set to update automatically to ensure protection from the latest viruses and threats can be easily done. Moreover, keep the user operating system and web browser patches currently. If they are work for a company, they should make sure that their work computer at home complies with all of that companies IT security policies just like as they would if they were working from the office.

Lastly, keep it backed up. It means, the user should have an effective backup plan for every home office solution. All data should be backed up religiously and wisely, stored in a secure location. Knowing that an external hard drive that is stored in a locked cabinet can be an acceptable solution, as long as the user does not forget to take it out on a regular basis and run a backup. Cloud based solutions can also work as the user are secure and they compile with their employer's IT policies. It is easy to back data up but the hard part is to restoring it. It is sensible to test backups every once in a blue moon to make sure that the user can really restore data when they need it to.

Through employing these best practices, each individual can protect themselves against common Internet risks like computer virus and hackers such as ensuring a safer computing experience for professionals conducting business from home, as well as their families that utilize the same network.

On the other hand, the phone line also existing the phone wiring found in the most homes and can provide the fast services such as DSL. For the television they are using the same type of coaxial cable which provides cable internet. If you plan to connect only two computers you need is a network interface card (NIC) in each computer and a cable to run between them. If you want to connect many computers make sure there is an additional piece of equipment which is router.

Once you have all the equipments, you need to install it and configure the computers so they can connect to each other. Normally we need to depends on the type of networks and the existing hardware to connect several computers.

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Wireless Network

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A wireless network is a computer network that is not connected by cables. It is easiest and less expensive network. A wireless local-area network (LAN) uses radio waves to connect devices such as laptops to the Internet network and its applications. This type of network using radio waves instead of wired network. Without the present of wires make this type of network very flexible to the entire user.

For example,when you connect a laptop to WiFi hotspot at a cafe, hotel, airport lounge and so on it means you are connecting to the wireless network. Some of them are believed wired networks were faster and more secure than wireless networks. But actually wireless networking standards and technologies have eroded to those speed and security differences.

The advantages of a wireless network will first of all the productivity. It can access to the Internet to get help of the applications. Morever, easy to setup the settings. No need to use string cables, so installation can be done in a quick method. Finally the advantages will be expandable which means it easily expand wireless network with existing equipment whreas wired network may requires additional wiring.

In addition, if the user wants to build a wireless network theu should need the wireless router. The signal from a wireless router extends about 100 feet in all the directions. It is also depending on the size and shape of a user home and the range of the router.

Well there are many reasons that strangers were stoled our private data. They could gain access to private data on network and simply steal bandwidth thus it slowing down the connection when using it. They simply like to hack people’s profile to gain information.

However, there are some ethics that user should take the precautions to protecting the network from computer virus and hackers. The user send or receive the data, the hacker could intercept easily to get access to user wireless network. So in order to prevent all those things we should take the precautions as stated as below.

Firstly, a user must rottenly change the default administrator password on their home router and wireless access points. This is just for obvious reasons depending on the user.

Secondly, the user should never enable any remote management on their home router or access point. This is just in case the user does not want anyone to access into their router from the Internet.

Lastly, a user must often configure their network to use strong encryption. The earliest attempt at WiFi security, Wired Equivalent Protocol (WEP) proved deeply flawed and very easy to hack. WiFi Protected Access (WPA) and in particular WPA2 (which features tough AES encryption) has gone a long way to rectifying this glaring defect. Even too many wireless networks (WLANs) remain unprotected and open to intruders.

CONCLUSION

As the conclusion, a Wired Network and Wireless Network each one have its own advantages and disadvantages.

There is a many ways to make sure that both networks are in security condition. The user can maintain the computer in good condition at all time.

All the risk from hackers and computer virus need to be prevent wisely by the user. It is all depending on how we as the user manage to prevent the networks from any computer virus and hackers by following all the steps given above.

INTRODUCTION

OSI stands for Open System Interconnection is defines netwoking framework to implement protocols in seven layers.

There are 7 layers of OSI model. The first layer is physical layer, second layer is data link layer, third is network layer, fourth is transport layer, fifth is session layer, sixth is presentation layer, and seventh is application layer.

Each of the layer has it owns protocols.

QUESTION 2

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OSI defines as Open System Interconnection it called as reference model for how messages could transfer between two points in a telecommunication network. Its purpose is to guide product implementors so that their products will consistently work with one another.

OSI contains defines seven layers of functions that take place at each end of a communication. Lets explain one by one of the layers. Firstly will be physical layer. This layer conveys the bit stream like electrical impulse, light or radio signal through the network.

As normal physical layers is actually communicates direct with the communication medium. It contains sending bit and receiving bit. The bit means binary digit is a most basic unit of information in data communication flow. Fast Ethernet, RS232 and ATM are the protocols with the physical layer components.

Secondly will be data link layer. At this layer, data will be packets are encoded and decoded into bits. It handles errors in the physical layer and also furnishes transmission protocol knowledge and also frame sychronization. The transmission are synchronises and is responsible for error-control on frame-level which means a frame is a block of data within network-specific addressing information.

This data link layer is divided into sub layers which are The Medis Access Control(MAC) layer and the Logical Link Control(LLC) layer. The MAC sub layer controls how the computer access to the data and permission to transmit it through network. Whereas, LLC layer controls frame synchronization, error checking and flow control.

Access-methods for Ethernet and Token Ring are carrying by this layer also. It also provides the address information for the physical layer on top of the frame of transmitted. The examples of data link layer are start indicator, source address, destinations address, control, data, and error control.

Moreover, data link layer provides frame sequencing which means transmit and receive frames in sequential order. Not only this it also provides frame traffic control it tells the transmitting node to "back-off" when no frame buffers are available. The examples of data link layer are start indicator, source address, destinations address, control, data, and error control.

In addition, network is also one of the OSI layer. Controlling the operation of the subnet, decide which physical path the data need to take based first, service of priority, and many others are the jobs of the network layer. Network layer provides the routes frame among network. The subnet traffic control can instruct a sending station to throttle back its frame transmission. Communications of subnet means the network layer software residing in the subnet intermediate systems can recognize them and use them to route data to the destination address by the network layer software must build headers.

On the other hand, transport layer will be the fourth layer. It ensures that messages are delieved in error-free, sequential order and with no losses or any duplication. It helps to relieves the highe layer protocols from any concern with the help of transfering data between them and their peers.

It provides message segmentation, message acknowledgement and message traffic control. This layer can accpet relatively large mesage but there is a size limit imposed by the network. This layer also have end-to-end layers which is not concerned.

Fifth layer is session. This allows session establishment between processes running on different stations. Session layer got two sessions which establishment session and support session. Establishment session allow two application processes on different machines to establish and terminate a connection. However, support session allow those processes to communicate over the network, perform security, log in, name regonition and so on.

The presentation layer is a sixth layer. In this layer, data to be presented to the application layer. It can be seen the translator for the network. At the standing station, this layer might be translate data from a format used by the application layer into common format, then translate the common format to a format known to the application layer at the receiving station.

Not only this, the presentation layer provides character code translation for example ASCII to EBCDIC. It provides three type of data. Data conversion is a bit in order CR-CR/LF,integer-floating point, and so on. Data compression it reduces the number of bits that need to be transmitted on the network. Data encryption which encryt data for security purposes. For example password encryption.

Finally, application layer is the last layer of the OSI model. Application layer supports application and end-user processes. The network layer information is added up in the part of a header, which is appended to the starting of the data. Protocol Data Unit or in short form PDU are used in describing the combination of the control information for a layer together with the data from the next high layer. Each of the layers appends a header to the PDU that stay next higher layer receives. The data would fully field for each other layer consisting of the PDU for the next higher layer.

At this layer provides application services for file transfers, email and the other network software services. Telnet and File Transfer Protocol (FTP) are applications that exist entirely in the application level. Furthermore, application layer containing a large number of commonly needed functions such as resource sharing and device redirection, remote file access, remote printer access, communication interprocesses, management of network, services directory, electronic message for example mailing, and network virtual terminals.

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Example of seven (7) layers of OSI model

CONCLUSION

As the conclusion, the Open Systems Interconnect (OSI) model has seven layer such as physical layer, data link layer, network layer, transport layer, session layer, presentation layer, and application layer.

All the explanation from the beginning with the lower level in the hierarchy which is the physical layer, and proceeding to the highest level which is the application layer.

There are a lot of advantages of the OSI model. Firstly, it encrypt data for security purposes. Secondly, it reduce the complexity for example, it divides the network connection into smaller and simpler parts.

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