Unit 1 – Networking (A1S1)
An introduction to provide an overview of your report
The Application Layer is the most important and most visible layer in computer networks. Applications reside in this layer and human users interact via those applications through the network. The best network type must be chosen to reflect the best way forward on how the data must be shared and transferred between the three (3) different locations. Such data can be accessed from LAN or WAN and by evaluating the ideal topology within a particular location and amongst the three premises. One must keep in mind the VPN for employees who need to make use of teleworking – thus a terminal must reach a particular server from anywhere in Malta and / or outside the shores. Albeit Flexi Corp hosts a cloud, different type of servers are needed to be used as Mail Server, Web Server, FTP Server and / or more. Furthermore, rather than just be equipped with reliable servers which offers good optimisation, Flexi Corp must furnish for data redundancy in case for natural disaster and for data queuing with the use of load balancer. Due to the fact that Flexi Corp cannot afford pausing the work for a few hours, it is very paramount that when upgrading the systems, database or any other software the company must be proficient with having a clone of each server so not to stop the daily run.
In this type of infrastructe, given that all premises are located few kilometres away and the type of service Flexi Corp offers (i.e. accountancy), it should consider the financial part thus, although it must own a fine network structure, the company must be equipped for scalability but to a certain point.
P1 Discuss the benefits and constraints of different network types and standards.
Also known as peer-to-peer (P2P) is a network where two or more computers are able to access files and devices such as printers without having a separate server computer / software. This type of network can be an ad hoc connection that is, a couple of computers connected via a Universal Serial Bus to transfer files. A P2P network also works as a permanent infrastructure that links a half-dozen computers in a small office over copper wires. It can also be a network on a much greater scale in which special protocols and applications set up direct relationships among users over the Internet. Early in the days P2P was famous for downloads of files of others such as music and videos. One famous web application which was used to download this type of files was LimeWire Music.
P2P file sharing has both advantages and disadvantages. The following are some of the pros of P2P file sharing.
? Pros of P2P file sharing
• Less expensive. Many P2P file sharing is free (although the legality of this is questionable), making it a top option for users who don’t want to spend a lot of money for an entire CD just to get one song. P2P file sharing allows users to pick and choose their downloads. Even the legal fee-based versions of P2P file sharing are less expensive;
• Speed. P2P file sharing is fast and easy. People who want to download legally such things like Operating System (e.g. Windows) updates and the like can do so quickly, as P2P files contains these large files and make them more manageable, allowing for faster downloads. P2P services allow users to download little chunks of files rather large files, from many different people. This implies to be faster;
• No servers. That is probably the biggest advantage that P2P network offers. Data isn’t being stored on one central server. Due to this fact, one does not have to worry on the ability of the server.
? Cons of P2P file sharing
• Not always legal. While there are legitimate sites for legally exchanging files, many P2P sites have come under the spotlight for sharing music and videos illegally. Downloading music, videos, and many other types of files is often in violation of copyright laws. Hefty fee are attached for such actions;
• Bandwidth. When a computer is connected to many computers its performance will be slowed down because as a member of the P2P network, it will be sharing information in the shared folders;
• Spyware. Many P2P networks, once downloaded, are filled with spyware and malware. A solution for this issue is to install a good anti-virus, firewall and spyware application.
Unlike the P2P network, the client-server works with one centralized and powerful computer (server) which is the hub of many less powerful terminals (clients) connected with each other. This means that the clients access data and run programmes from the server. In simplified context the client-server approach can be described as a customer sitting at a restaurant waiting for the server to come by and take his order. The client, which can be a laptop / desktop, a smartphone, or any computerized device, can make a request from the server.
The client makes use of the network as a way to connect and communicate with to the server. Like-wise to the customer who speaks to his server, the client uses the network to send and receive messages about its order / request. The server will take the request and make sure that the request is valid. If everything checks out okay, then the server will fetch the request and serve the client.
The server can make a request from the client as well. It may want to check up on the status of the client, or ask if it has received any security patches, or if it still needs resources from the server. If not, the server will close the connection in order to free up network traffic.
Imagine a server standing next to a customer who just stares at the menu without ordering anything? After 15 minutes, it would be a good idea for the server to leave and checks on other clients.
? Pros of client-server
• More control over the data. Efficiency over all files due to the fact that they are stored in a central location;
• Backups. Having a centralised server, will have the ability to do frequent back-ups of all / partition of the data;
• Security. Having firewalls with access logins decreases data theft / lost. If this is the case, a track of what has happened is available;
? Cons of client-server
• Specialised staff. Specialised personnel such as Network Engineers and Network Operating Systems are needed to maintain good quality network operation;
• Financial cost. It requires a lot of money to buy a server and its respective software and media;
• Server dependence. There is a reliance on the central server, if it fails or something happens to it, no work can be done.
Cloud based networking, is the type of network which is access its resources from a centralised third-party provider using wide area network (WAN). This networking is related to the concept of cloud computing , where centralized computing resources are shared for the employees or clients. Here, the network can be shared as well as the computing resources. Presently it has become a trend to push more for this concept, because fewer employees and/or customer devices and applications are needed to manage the network. A renowned cloud based network is Microsoft Azure. It offers a variety of computing services staring from servers, storage, databases, networking, software, analytics, intelligence and more.
? Pros of cloud
• Cost Efficient. It eliminates the capital expense of buying software and hardware and setting up and maintain on-site data centres, servers, electricity for power and cooling and specialised staff for managing the infrastructure;
• Easy Access to Information. Once registered with one of these cloud providers, the clients can access their information from anywhere, where there is an Internet connection;
• Almost Unlimited Storage. Most of the cloud providers offers unlimited storage capacity. Hence, when a company commits itself to cloud, there is no worrying about running out of storage space or increasing the current storage space availability.
? Cons of client-server
• Prone to hacking. Storing information in the cloud could make any company vulnerable to external hack attacks, threats or data theft. Anything which is on the internet, is not completely secure and hence, there is always the lurking possibility of stealth of sensitive data;
• Security in the Cloud. Another major issue which the cloud faces is that of security issues. One should consider that he is ‘sharing’ his information which might be sensitive to a third-party cloud service provider. This could potentially put your company at great risk;
• Internet Connectivity. Running all or some of the applications in the cloud requires to maintain a consistent internet connection (W/LAN, 3/4G). However If the cloud-based service providers loses connectivity, or if the internet service provider (ISP) experiences an outage (e.g. natural issues), the company might be out of business until it is connected again with the cloud provider.
Centralise network which is also called centralised server-structure is where all users connect to a central server, which is the solo-acting agent for all communications. This server would store all the communications and the users’ account information. Most public instant messaging platforms use a centralized network. Centralized computing enables the deployment of all of a central server’s computing resources, administration and management. The central server, in turn, is responsible for delivering application logic, processing and providing computing resources (both basic and complex) to the attached client machines.
? Pros of centralised network
• Control over own data. When it is maintained by central server, it requires less times and also few staff or engineer. It is controlled by one server and also maintained by administrator. The multipurpose of this is that each one can save and backup their data on to the central data server and can access from there;
• Physical control. Another advantage is that of having control on when and how upgrades and deployment of softwares can occur whilst having everything in the house.
? Cons of centralised network
• Cost. Equipment and hardware is highly expensive to buy and build up a centralised server. Another cost in maintaining a centralisation network is electricity;
• Storage. A lot of storage is required to keep up all the necessary data and back-up the most important data.
Network virtualization (NV) is expressed by the ability to develop logical / virtual networks that are separated from the underlying network hardware to safeguard the network which can integrate better with and support increasingly virtual environments. Over the past decade, lots of companies and organizations have been adopting to this type of technology at an accelerated rate. Virtualization is the ability to replicate a hardware platform, such as a server, storage device or network resource, in software. The functionalities are decoupled from the hardware and simulated in a virtual instance. Its ability to operate just like the norm, hardware solution would do. The virtual instances of these resources is hosted by a hardware support. Most of the hardware can be general and off-the-shelf platforms. In addition, one hardware platform can be used to support multiple virtual devices/machines. As a result, a virtualized solution is typically much more portable, scalable and cost-effective than a traditional hardware-based solution.
? Pros of virtualised network
• Capital expenditure savings. It helps businesses to reduce their IT costs by requiring less hardware servers and related resources to achieve the same level of computing performance, availability and scalability;
• Green Environment. It reduce the size of their hardware and server footprint, lower the energy consumption, cooling power and data centre buildings, thus resulting in lower costs.
? Cons of virtualised network
• Time spent learning. Server virtualization might be challenging to understand. IT professionals who feel completely confident in their ability to manage and understand physical servers require some time to fully understand how to work a virtualized one;
• Upfront costs. The initial investment in the virtualization software may be a bit hefty, and possibly additional hardware might be required to accommodate the virtualization. It may also depends on the existing business’s network.
IEEE 802.1X is a standard component of the IEEE 802.11 network protocol group. It was established by the Institute of Electrical and Electronics Engineers (IEEE). IEEE 802.1X is attached to IEEE 802.11 protocols to empower the wireless network security. It controls access to wireless and/or virtual local area networks (VLAN) and implies data traffic policies based on user account access. IEEE 802.1X ensures a user authentication framework where network access is rejected upon a failed authentication. Built for wired networks, IEEE 802.1X requires very little processing power and is well-suited to wireless LAN applications.
? Pros of IEEE 802.1X
• Scalability. It allows more control and management of users, devices, profiles, certificates and more from a single management node and the adjust the solutions for the profile management to allow automated or simplified roll-backs of the technology;
• Ease of use. From an end-user perspective, this type of component is user-friendly due to the fact that it asks the user to enter the network credentials to get authenticated. Usually this happens once unless network credentials have been changed.
? Cons of IEEE 802.1X
• Cost. For WIFI usage, it requires a lot of network points such as routers, thus it requires a bit of costs in implanting these points and all data wiring;
• Account. End-users cannot make use of the WIFI or internet prior having their own credentials. Thus this means that new employees have to wait to have their account set-up. Some companies they may take a week to set-up new accounts.
TO ASK ON CONCEPTUAL MODEL
P1 Explain the impact of network topology, communication and bandwidth requirements.
What Are Network Topologies?
Network Topology refers to the layout of a network and how different terminals within the same network are connected with each other and how data is being exchanged amongst. Topologies are either physical, which means a physical layout of devices on a network, or else logical that is the way that the signals act on the network media, or the way that the data passes through the network from one terminal to the next. The Ethernet protocol is a common logical bus topology protocol. LocalTalk is a common logical bus or star topology protocol. IBM’s Token Ringis a common logical ring topology protocol. A network’s logical topology is not necessarily the same as its physical topology. For example, twisted pairEthernet is a logical bus topology in a physical star topology layout. While IBM’s Token Ring is a logical ring topology, it is physically set up in a star topology.?
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