LP4-Networking-1 (1).pdf

4 4 | Networking 1 63 UNIT 4: Types of Internet Connection Backups, Recovery & Server Security 4.0 Intended Learning Outcomes On completion of the module, you should be able to: a....

4 4 | Networking 1 63 UNIT 4: Types of Internet Connection Backups, Recovery & Server Security 4.0 Intended Learning Outcomes On completion of the module, you should be able to: a. Classify search engines and social networking. b. Identify different Types of Internet Connection. c. Discuss different platforms used in social networking. d. Determine backups, recovery and server security in accessing internet. 4.1 Introduction Connecting an electronic device to the internet has become easy as there are different ways to do that. Different hardware uses various connection speeds to get connected with the device or devices. With time people are now availing faster internet connection. However, there are a lot of different type’s internet connections that are now available both in the homes and outside. When determining which type of Internet speed and Internet connection is right for you or your family, it's important to understand the distinction between each connection. In today's age, there are numerous ways to connect laptops, desktops, mobile phones, gaming consoles, e-readers and tablets to the Internet. Some of the most widely used Internet connections are described below. 4.2 Types of Internet Connection Dialup, Broadband, Lease line Dial-up Connection Dial-up connection uses telephone line to connect PC to the internet. It requires a modem to setup dial-up connection. This modem works as an interface between PC and the telephone line. There is also a communication program that instructs the modem to make a call to specific number provided by an ISP. Dial-up connection uses either of the following protocols: 1. Serial Line Internet Protocol SLIP 2. Point to Point Protocol PPP The following diagram shows the accessing internet using modem: 4 4 | Networking 1 64 Lease Line Leased lines are most commonly rented by businesses to connect branch offices of the organization. Leased lines guarantee bandwidth for network traffic between locations. For example, T1 leased lines are common and offer the same data rate as symmetric DSL. Individuals can theoretically rent leased lines for high-speed internet access, but their high cost deters most people, and far more affordable home options are available with higher bandwidth than a simple dial-up phone line, including residential DSL and cable internet broadband service. Fractional T1 lines, starting at 128 Kbps, reduce this cost somewhat. They can be found in some apartment buildings and hotels. Using a Virtual Private Network (VPN) is an alternative technology for using a leased line. VPNs allow an organization to create a virtual and secure connection between locations as well as between those locations and remote clients such as employees. Broadband For consumers who are looking for internet access, a leased line is usually not a feasible option. There are fast broadband internet connections available that are much more affordable. Access to these broadband services varies depending on location. In general, the farther from a populated area you live, the fewer broadband options are available. Broadband options available to consumers include:  Digital Subscriber Lines: DSL service uses existing telephone wiring to deliver broadband service. Voice telephone service does not use all of the broadband capacity of the telephone system's copper twisted pair of wires, and DSL utilizes the free space. 4 4 | Networking 1 65  Cable Modems: Cable service represents another pre-existing wire into many homes. The coaxial cable is used to carry the additional broadband internet signal.  Wireless Broadband: Wireless Broadband uses a radio link between the user's location and the service provider's facility. The range is limited, making availability more limited as well.  Wireless Cell Phone Internet: Broadband service is often available using 3G and 4G cellular signals that are commonly used by smartphones. Though not as fast as DSL or cable and expensive if you have high data usage, this option is faster than dial-up for rural customers.  Satellite Broadband: Satellite broadband service may be the only broadband service available in rural areas. The service often accompanies satellite television service and uses the same receiver for downloading. The speed is not as fast as other services, but it is still much faster than dial-up service. The main downside is the costly price tag for equipment and the service. Wi-Fi, Wimax, 2G, 3G, 4G (LTE), 5G Wi-Fi Wi-Fi stands for “wireless fidelity”. However since most of our WLANs are based on those standards, the term Wi-Fi is used generally as a synonym for WLAN. Wi-Fi is a popular technology which allows any electronic device to exchange and transfer data wirelessly over the network giving rise to high speed internet connections. Any device which is Wi-Fi enabled (like personal computers, video game consoles, Smartphone, tablet etc.) can connect to a network resource like the internet through a wireless network access point. Now such access points also known as hotspots have a coverage area of about 20 meters indoors and even a greater area range outdoors, this is achieved by using multiple overlapping access points (Chan, 2005),(Intel Corp,2003). However, with all such features, Wi-Fi also suffers from certain shortcomings. Wi-Fi is known to be less secure than wired connections (such as Ethernet) because an intruder does not need a physical connection. Web pages that use SSL are secure but unencrypted internet access can easily be detected by intruders. Because of this, Wi-Fi has adopted various encryption technologies. The early encryption WEP, proved easy to break. Higher quality protocols (WPA, WPA2) were added later on. An optional feature added in 2007, called WiFi Protected Setup (WPS) was deployed, but it also had a serious flaw that allowed 4 4 | Networking 1 66 an attacker to recover the router's password. The Wi-Fi Alliance has since updated its test plan and certification program to ensure all newly certified devices resist attacks. But security is still a major concern (Cam- Winget, et al., 2003), (Chandra Shekar, et al., 2005-2008). WiMAX WiMAX stands for “World Interoperability for Microwave Access”. It is a standard typically based on global interoperability including ETSI HIPERMAN, IEEE 802.16d-2004 for fixed, and 802.16e for mobile high-speed data. WiMAX is gaining popularity as a technology which delivers carrier-class, high speed wireless broadband at a much lower cost while covering large distance than Wi-Fi (Cam- Winget, et al., 2003). It has been designed to be a cost effective way to deliver broadband over a large area. It is intended to handle high-quality voice, data and video services while offering a high QoS (Westech Comms Inc., 2010). WiMAX operates in between 10 and 66 GHz Line of Sight (LOS) at a range up to 50 km (30 miles) and 2 to 11GHz non Line-of-Sight (NLOS) typically up to 6 - 10 km (4 - 6 miles) for fixed customer premises equipment (CPE). Both the fixed and mobile standards include the licensed (2.5, 3.5, and 10.5 GHz) and unlicensed (2.4 and 5.8 GHz) frequency spectrum. However, the frequency range for the fixed standard covers 2 to 11 GHz while the mobile standard covers below 6 GHz. Depending on the frequency band, it can be Frequency Division Duplex (FDD) or Time Division Duplex (TDD) configuration. The data rates for the fixed standard will support up to 75 Mbps per subscriber in 20 MHz of spectrum, but typical data rates will be 20 to 30 Mbps. The mobile applications will support 30 Mbps per subscriber, in 10 MHz of spectrum, but typical data rates will be 3 - 5 Mbps. Applications of fixed WiMAX (802.16-2004) include wireless E1 enterprise backhaul and residential ‘last mile’ broadband access, while 4 4 | Networking 1 67 applications for mobile WiMAX (802.16e) include nomadic and mobile consumer wireless DSL service. Other WiMAX applications include: connecting Wi-Fi hotspots with each other and to other parts of the Internet; providing a wireless alternative to cable and DSL for last mile (last km) broadband access. On flexibility, WiMAX can be deployed in any terrain across all geographical areas. Second Generation (2G) 2G refers to the second generation of mobile networks based on GSM. The radio signals used by the 1G network were analog, while 2G networks were digital. 2G capabilities were achieved by allowing multiple users on a single channel via multiplexing. During 2G, Cellular phones were used for data along with voice. Some of the key features of 2G were: o Data speeds of up to 64 kbps o Use of digital signals instead of analog o Enabled services such as SMS and MMS (Multimedia Message) o Provided better quality voice calls o It used a bandwidth of 30 to 200 KHz Third Generation (3G) The 3G standard utilizes Universal Mobile Telecommunications System (UMTS) as its core network architecture. 3G network combines aspects of the 2G network with new technologies and protocols to deliver a significantly faster data rate. By using packet switching, the original technology was improved to allow speeds up to 14 Mbps. It used Wide Band Wireless Network that increased clarity. It operates at a range of 2100MHz and has a bandwidth of 15-20MHz. Some of the main features of 3G are: o Speed of up to 2 Mbps o Increased bandwidth and data transfer rates o Send/receive large email messages o Large capacities and broadband capabilities International Mobile Telecommunications-2000 (IMT-2000) were the specifications by the International Telecommunication Union for the 3G network. Theoretically, 21.6 Mbps in the max speed of HSPA+. Fourth Generation (4G) The main difference between 3G and 4G is the data rate. There is also a huge difference between 3G and 4G technology. The key technologies that have made 4G possible are MIMO (Multiple Input Multiple Output) and OFDM (Orthogonal Frequency Division Multiplexing). The most important 4G standards are WiMAX and LTE. 4 4 | Networking 1 68 While 4G LTE is a major improvement over 3G speeds, it is technically not 4G. What is the difference between 4G and LTE? Even after it was widely available, many networks were not up to the required speed of 4G. 4G LTE is a “fourth generation long term evolution”, capable of delivering a very fast and secure internet connection. Basically, 4G is the predetermined standard for mobile network connections. 4G LTE is the term given to the path which has to be followed to achieve those predefined standards. Some of the features of 4G LTE are: o Support interactive multimedia, voice, video. o High speed, high capacity and low cost per bit (Speeds of up to 20 Mbps or more.) o Global and scalable mobile networks. o Ad hoc and multi-hop networks. Following is the comparison between 4G and 5G speeds: Theoretical 5G vs 4G speed Live 5G vs 4G speed test performed via RantCell App Fifth Generation (5g) 5G uses the rarely used radio millimeter bands in the 30 GHz to 300 GHz range. Testing of 5G range in mmWave has produced results approximately 500 meters from the tower. Using small cells, the deployment of 5G with millimetre wave based carriers can improve overall coverage area. Combined with Beamforming, small cells can deliver extremely fast coverage with low latency. Low latency is one of 5G’s most important features. 5G uses a scalable orthogonal frequency-division multiplexing (OFDM) framework. 5G benefits greatly from this and can have latency as low as one millisecond with realistic estimates to be around 1 – 10 seconds. 5G is estimated to be 60 to 120 times faster than the average 4G latency. 4 4 | Networking 1 69 Active antenna 5G encapsulated with 5G massive MIMO is used for providing better connections and enhanced user experience. Big 5G array antennas are deployed to gain additional beamforming information and knock out propagation challenges that are experienced at mmWave frequency ranges. Further, 5G networks clubbed with network slicing architecture enables telecom operators to offer on-demand tailored connectivity to their users that is adhered to Service Level Agreement (SLA). Such customised network capabilities comprise latency, data speed, latency, reliability, quality, services, and security. With speeds of up to 10 Gbps, 5G is set to be as much as 10 times faster than 4G. Following is a brief comparison of 2G, 3G, 4G, and 5G. Search Engine Search engines are websites or software that enables a person to find documents or other media on the internet. Most famous are, Google (originally called ‘BackRub’ and now a subsidiary of Alphabet) and Bing (formerly known as MSN search). There are thousands of smaller search engines on the internet, but few are used by more than a handful of real world people. Google still holds the majority share at 78%, but about 22% of search engine usage is for the other ‘major’ search engines. And that trend does not seem to be changing an awful lot. There was a brief period recently when the Firefox browser changed its default search engine from Google to Yahoo, and Google market share wavered, but the evidence is that those users are gradually reverting back to Google (once they’ve finally figured out where the setting is in Firefox to do this). A similar effect was seen following the roll out of Windows 10 which uses Bing as the default search provider in the new Edge browser. So when we talk about search engines today, we can almost use the words ‘Google’ and ‘search engine’ interchangeably. In fact, the word ‘search’ in common language has been replaced with ‘Google’ – “I’ll just Google the phone number for the restaurant” or “I just Googled myself, and immediately regretted it”. Social Networking Social networking is the use of Internet-based social media sites to stay connected with friends, family, colleagues, customers, or clients. Social networking can have a social purpose, a business purpose, or both, through sites like Facebook, Twitter, LinkedIn, and Instagram. Social networking has become a significant base for marketers seeking to engage customers. 4 4 | Networking 1 70 Despite some stiff competition, Facebook remains the largest and most popular social network, with 2.8 billion people using the platform on a monthly basis, as of Dec. 31, 2020. It was followed, in order of popularity, by Instagram, Facebook Messenger, Twitter, and Pinterest, according to Statistica. One of the most well-known types of social media is social networks. These networks allow users to connect with people and brands online. Social networks can help you:  Build brand awareness  Generate new leads  Build relationships with customers  Provide customer service  And more Many people call social networks “relationship platforms” because they allow people to connect and build a relationship. You can share information, photos, videos, and more through these sites. These platforms focus on sharing knowledge and connecting with people. Let’s take a look at three of the most popular types of social networks: Facebook 4 4 | Networking 1 71 With over 2.3 billion monthly active users, Facebook is one of the most popular social networks available to your business. Many people use these platforms to connect with family, friends, and brands. For your company, Facebook offers an excellent opportunity to connect with your audience. You can share:  Status updates  Photos  Videos  Links to content  Polls Facebook also offers paid advertisements that allow you to attract new followers to help grow your business. Twitter Twitter has over 326 million monthly active users. This platform is used similarly to Facebook, with users posting photos, videos, status updates, links, polls, and more. The most significant distinction between these social networks is the size of the message. Twitter’s unique attribute is that you only have 280 characters for each of your messages. This limit means that you need to get to the point with what you’re trying to say. Twitter also offers paid advertisements for your business. You can run a multitude of different ads to gain new followers and earn conversions for your business. 4 4 | Networking 1 72 LinkedIn LinkedIn boasts over 610 million users in more than 200 million countries and territories. This social network is a great place for professionals to connect. It’s an excellent platform for building professional relationships, sharing information, finding new jobs, and recruiting new candidates. You can also advertise to people who use LinkedIn. It’s a great place to target professionals interested in your business. Backups, Recovery & Server Security 4.3.1 Backups Application Critical business assets should be duplicated to provide redundancy and serve as backups. At the most basic level, fault tolerance for a server means a data backup. Backups are simply the periodic archiving of the data so that if there is a server failure you can retrieve the data. From a security point of view, there are three primary backup types with which we are concerned:  Full — All data is archived.  Differential — All changes since the last full backup are archived.  Incremental — All changes since the last backup of any type are archived. Full backup Full backup is the best backup strategy but it has drawbacks. Consider a scenario where you do a full backup at 1 a.m. each morning. You are concerned about the possibility of a server crash before the next full backup, so you want to do a backup every two hours as well. Which 4 4 | Networking 1 73 type of backup should you choose? Let’s consider each option and what would happen if the system crashes at 5:10 a.m. If you do a full backup every two hours beginning at 1 a.m., then when the system crashes at 5:10 a.m., you simply need to restore the 5:00 a.m. full backup. However, running a full backup every two hours is very time consuming and resource intensive, and it will have a significant negative impact on server performance. Differential backup In this scenario, you do a full backup at 1 a.m. and then perform a differential every two hours thereafter. When the system crashes at 5:10 a.m., you have to restore the full backup from 1 a.m. and the differential backup from 5 a.m. This takes just one more step than restoring the full backup. Keep in mind, however, that the differential backups are going to get larger each time you do them and thus more time consuming and resource intensive. Although they won’t have as much impact as the full backups, they will still slow down your network. Incremental backup In this scenario, you do a full backup at 1 a.m. and then an incremental backup every two hours. When the system crashes at 5:10 a.m., you need to restore the last full backup done at 1 a.m. and then each incremental backup since then — and they must be restored in order. This is much more complex task, but each incremental backup is small and does not take much time or resources to create. There is no single correct choice of what backup to use. The proper choice depends on your organization’s needs. Whatever backup strategy you choose, you must periodically test it. The only effective way to test your backup strategy is to restore the backup data to a test machine. One of the top best practices is to store your backups in geographically different places to prevent disasters such as acts of nature or accidents (e.g., hurricanes, fires or hard-disk failures) from destroying the business’s IT core. Backups should be performed incrementally across multiple disks and servers, and on different time schedules (daily, weekly and monthly). Preferably, these incremental backups should save a base copy and each modification should reflect only the changes to the base copy, or a closely matching previous version. This allows for proper versioning and can help to serve as a form of data control. 4.3.2 File Server In the client/server model, a file server is a computer responsible for the central storage and management of data files so that other computers on the same network can access the files. A file server allows users to share information over a network without having to physically transfer files by 4 4 | Networking 1 74 floppy diskette or some other external storage device. Any computer can be configured to be a host and act as a file server. In its simplest form, a file server may be an ordinary PC that handles requests for files and sends them over the network. In a more sophisticated network, a file server might be a dedicated network-attached storage (NAS) device that also serves as a remote hard disk drive for other computers, allowing anyone on the network to store files on it as if to their own hard drive. A program or mechanism that enables the required processes for file sharing can also be called a file server. On the Internet, such programs often use the File Transfer Protocol (FTP). 4.3.3 Email Server Email servers provide the communications backbone for many businesses. They typically run either as an additional service on a server or as dedicated systems. Putting an active virus scanner on email servers can reduce the number of viruses introduced into your network and prevent viruses from being spread by your email server. It is worth noting, though, that most scanners can’t read Microsoft’s open files; to scan Exchange mail stores, you need a specific email AV scanner, some of them even try to detect phishing, such technology is based on machine learning engine and has good perspectives combating social engineering attacks. Email servers are being inundated by automated systems that attempt to use them to send spam. Most email servers have implemented measures to prevent this. The threats, however, are becoming increasingly more sophisticated. You may be able to reduce these attempts to access your system by entering the TCP/IP addresses in your router’s ACL Deny list. Doing so will cause your router to ignore connection requests from these IP addresses, effectively improving your security. Such measures can be also done with spam filters. Proxy Server A proxy server provides a gateway between users and the internet. It is a server, referred to as an “intermediary” because it goes between end-users and the web pages they visit online. When a computer connects to the internet, it uses an IP address. This is similar to your home’s street address, telling incoming data where to go and marking outgoing data with a return address for other devices to authenticate. A proxy server is essentially a computer on the internet that has an IP address of its own. Proxy Servers and Network Security Proxies provide a valuable layer of security for your computer. They can be set up as web filters or firewalls, protecting your computer from internet threats like malware. 4 4 | Networking 1 75 This extra security is also valuable when coupled with a secure web gateway or other email security products. This way, you can filter traffic according to its level of safety or how much traffic your network— or individual computers—can handle. Some people use proxies for personal purposes, such as hiding their location while watching movies online. For a company, however, they can be used to accomplish several key tasks such as: 1. Improve security 2. Secure employees’ internet activity from people trying to snoop on them 3. Balance internet traffic to prevent crashes 4. Control the websites employees access 5. Save bandwidth by caching files or compressing incoming traffic Benefits of a Proxy Server Proxies come with several benefits that can give your business an advantage: 1. Enhanced security: Can act like a firewall between your system and the internet. Without them, hackers have easy access to your IP address, which they can use to infiltrate your computer or network. 2. Private browsing, watching, listening, and shopping: Use different proxies to help you avoid getting inundated with unwanted ads or the collection of IP-specific data. 3. Access to location-specific content: You can designate a proxy server with an address associated with another country. You can, in effect, make it look like you are in that country and gain full access to all the content computers in that country are allowed to interact with. 4. Prevent employees from browsing inappropriate or distracting sites: You can use it to block access to websites that run contrary to your organization’s principles. Also, you can block sites that typically end up distracting employees from important tasks. Some organizations block social media sites like Facebook and others to remove time-wasting temptations. 4 4 | Networking 1 76 Assessment Name: _____________________________ Course, Year & Section: ________________ Subject: ____________________________ Instructor: ____________________________ Part I: Identification Direction: Write your answer in a short bond paper _______________ 1. Websites or software that enables a person to find documents or other media on the internet. _______________ 2. Generation of mobile network where the data speed is of up to 64 kbps. _______________ 3. It is what “WI-FI” stands for. _______________ 4. It’s an alternative technology for using a leased line. _______________ 5. The range in radio millimeter band where fifth generation rarely use. _______________ 6. A computer responsible for the central storage and management of data files so that other computers on the same network can access the files. _______________ 7. The service often accompanies satellite television service and uses the same receiver for downloading. _______________ 8. It can act like a firewall between your system and the internet. _______________ 9. A standard typically based on global interoperability including ETSI HIPERMAN, IEEE 802.16d-2004 for fixed, and 802.16e for mobile high-speed data. _______________ 10. This modem works as an interface between PC and the telephone line. 4 4 | Networking 1 77 Part II: True or False _______ 1. File servers provide the communications backbone for many businesses. _______ 2. A proxy server is essentially a computer on the internet that has an IP address of its own. _______ 3. Without an enhanced security, hackers have easy access to your IP address, which they can use to infiltrate your computer or network. _______ 4. A file server does not allow users to share information over a network without having to physically transfer files. _______ 5. With speeds of up to 10 Gbps, 5G is set to be as much as 10 times faster than 4G. _______ 6. Proxy server can access location-specific content. _______ 7. Running a full back-up every two hours is very time consuming and resource intensive, and it will have a significant negative impact on server performance. _______ 8. Social networking has become a significant base for marketers seeking to engage customers. _______ 9. Lease line allow an organization to create a virtual and secure connection between locations as well as between those locations and remote clients such as employees. _______ 10. A program or mechanism that enables the required processes for file sharing can also be called a file server. 4 4 | Networking 1 78 Part III: Enumeration State three primary back-up types of retrieving data. 1. ____________________ 2. ____________________ 3. ____________________ Give at least 5 platforms used in social networking. 1. ____________________ 2. ____________________ 3. ____________________ 4. ____________________ 5. ____________________ Give at least 2 benefits of proxy server. 1. ____________________ 2. ____________________ 4 4 | Networking 1 79 4.3 References https://www.tutorialspoint.com/internet_technologies/pdf/internet_connec tivity.pdf https://www.lifewire.com/definition-of-leased-line-817871 https://rantcell.com/comparison-of-2g-3g-4g-5g.html https://arxiv.org/ftp/arxiv/papers/1302/1302.2247.pdf https://www.blackboxecom.com/data/documents/01%20- %20Introduction%20to%20Search%20Engines.pdf https://www.investopedia.com/terms/s/social- networking.asp#:~:text=Social%20networking%20is%20the%20use,Twitter%2 C%20LinkedIn%2C%20and%20Instagram. https://www.webfx.com/blog/social-media/types-of-social-media/ https://searchnetworking.techtarget.com/definition/file-server https://www.fortinet.com/resources/cyberglossary/proxy- server#:~:text=A%20proxy%20server%20provides%20a,it%20uses%20an%20I P%20address 4.4 Acknowledgement All the figures and information contained in this module were taken from the references enumerated above.