Unit 2 The Network Infrastructure for E-Commerce

Unit 2: The Network Infrastructure for E-Commerce Contents: 1. Introduction to Information Superhighway (I-Way) 2. Components of the I-Way 3. Internet as a network infrastructure. Wireless Application Protocol: Wireless Application Protocol (WAP), Architecture of WAP; Working of WAP Wireless Technologies: ADSL, WiMAX, WLAN, WMAN, Wi-Fi, UMTS (3G), LTE (4G), (5G NR). 4. Security Issues related to Wireless Communications. Introduction to Information Superhighway (I-Way)  Global network of computers that, potentially, will connect most of world's individuals, firms, and organizations. It is envisioned to provide very high speed access to information in all forms (text, graphics, audio, video) via a telephone or wireless connection. The term was first used in 1985 by Al Gore.  The Information Superhighway is very much a physical network, an infrastructure of modern Highcapacity, interactive electronic pipeline providing integrated services. I-way links everyone at home or office to everything else.  The Information Superhighway is a physical network, facilitating the broadband, two-way transmission of any type of digital information, within its own virtual space.  Any e-commerce application will need the I-Way infrastructure in the same manner as any normal business would require the interstate highway network to carry goods from one place to the other.  I-Way is a network of interconnected data highways of several types: 1. Cable TV wires 2. Telephone wires 3. Optical fibers 4. Cellular and satellite 5. Radio and microwave-based wireless  I-Way is an interactive two-way high-capacity method of transporting information and services. IWay is applicable in large volume e-commerce applications as it provides traffic-free telecommunication service. I-Way helps organizations, firms and companies in upgrading their network infrastructure.  It also helps companies and organizations in recognizing the following: 1. Their infrastructure 2. Ways to change their business 3. Transaction strategies (marketing, advertising, etc.) 4. Ways to sell their products and services 5. Ways to change their relationship with the customerComponents of the I-Way There are three main components in I-Way: 1. Network Access equipment 2. Local Access components 3. Global Access componentsNetwork access equipment To access any network, specific equipment is required at the customer and this enables the consumer to access the network. It consists of hardware, such as routers, switches and access devices, such as computers and set-top boxes. Software platforms are browsers and operating systems. Local access component Local access component is the link between businesses, homes, schools and organizations to the main communication point also referred to as the ‘last mile’. Last mile connection represents a tremendous investment that cannot be easily replaced or overlooked in any network strategy. It provides the following types of connections: (a) Telephone-based channel (b) Cable-based last channel (c) Electrical-based last channel (d) Wireless-based last channel Global access component Nowadays, e-commerce activities are not limited to any country; and with the world becoming a global village, a proper network infrastructure is required to connect people and businesses across the world. These types of networks include: (a) Long distance networks (via coaxial cable or fiber-optic cable) (b) Satellite Internet as network infrastructure Backbone High-bandwidth fiber optic cable that transports data across the Internet Network Service Provider (NSP): Owns and controls one of the major networks comprising the Internet backbone Bandwidth Measures how much data can be transferred over a communications medium within a fixed period of time; is usually expressed in bits per second (bps), kilobits per second (Kbps), or megabits per second (Mbps) Network Access Points and Metropolitan Area Exchanges  One of the hubs where the backbone intersects with regional and local networks, and where the backbone owners connect with one another.  Metropolitan Area Exchanges (MAEs) another name for one of the hubs where the backbone intersects with regional and local networks.Campus Networks Generally local area networks operating with a single organization that leases access to the Web directly from regional and national carriers Internet Service Providers Firm that provides the lowest level of service in the multi-tiered Internet architecture by leasing Internet access to home owners, small businesses, and some large institutions. Narrowband The traditional telephone modem connections, now operating at 56.6 Kbps Broadband Refers to any communication technology that permits clients to play streaming audio and video files at acceptable speeds -- generally above 100 Kbps Broadband service is based on DSL, cable modem, telephone (T1 and T3 lines), and satellite technologies. Cable modem It refers to a cable television technology that piggybacks digital access to the Internet using the same analog or digital video cable providing television signals to a home. Cable Internet is a major broadband alternative to DSL service, generally providing faster speeds and a “triple play” subscription: telephone, television, and Internet for a single monthly payment. Digital Subscriber Line (DSL) It is a telephone technology that provides high-speed access to the Internet through ordinary telephone lines found in a home or business. Service levels range from about 768 Kbps up to 7 Mbps. T1 An international telephone standard for digital communication that offers guaranteed delivery at 1.54 Mbps T3 An international telephone standard for digital communication that offers guaranteed delivery at 45Mbps Satellite Satellite companies provide high-speed broadband Internet access, primarily to homes and officeslocated in rural areas where DSL or cable access is not available Internet, Intranet and Extranet Internet • The internet is the global system of interconnected computer networks that server billions of users worldwide. • It is the network of networks. • It allows computers on different kinds of networks to interact with each other. • It is the most common information super highway. • It is a public network.Intranet Intranet is defined as private network of computers within an organization with its own server and firewall. Intranet is system in which multiple PCs are networked to be connected to each other. PCs in intranet are not available to the world outside of the intranet. Usually each company or organization has their own Intranet network and members/employees of that company can access the computers in their intranet. Extranet • It is an Intranet that can be accessed by the permitted users over the Internet in a secure way. • It is a controlled private network that allows access to partners, vendors and suppliers or an authorized set of customers – normally to a subset of the information accessible from an organization's intranet. • It can be used for Inter-organization services like suppliers, buyers and distribution management. Internet vs Intranet Internet Intranet It is a public network. It is a private network. It is not owned by particular organization. It is owned by a particular organization or group of organizations. It connects large number of computers worldwide. It connects limited number of computers owned by an organization or group of organizations. It can be used by any user. It can be used only by the permitted used such as employee, customer of the organization. It contains data and information targeted for all the users. It contains data and information targeted only to the users of the organization. The security is usually low. The security is usually higher. Wireless Application Protocol  WAP stands for Wireless Application Protocol.  It is a protocol designed for micro-browsers and it enables the access of internet in the mobile devices.  It uses the mark-up language WML (Wireless Markup Language and not HTML), WML is defined as XML 1.0 application.  It enables creating web applications for mobile devices.  In 1998, WAP Forum was founded by Ericson, Motorola, Nokia and Unwired Planet whose aim was to standardize the various wireless technologies via protocols.  WAP protocol was resulted by the joint efforts of the various members of WAP Forum.  In 2002, WAP forum was merged with various other forums of the industry resulting in the formation of Open Mobile Alliance (OMA). WAP achieved some popularity in the early 2000s.  From the 2010s it had been largely outdated by more modern standards.  Most modern handset internet browsers now fully support HTML, so they do not need to use WAP markup for web page compatibility, and therefore, most are no longer able to render and display pages written in WML, WAP's markup language.  Most modern handset internet browsers now support full HTML, CSS, and most of JavaScript, and do not need to use any kind of WAP markup for webpage compatibility.  The list of handsets supporting HTML is extensive, and includes all Android handsets, all versions of the iPhone handset, all Blackberry devices, all devices running Windows Phone, and many Nokia handsets. Architecture of WAP WAP is designed in a layered fashion, so that it can be extensible, flexible, and scalable. The WAP protocol stack is divided into five layers − 1. Application Layer: This layer contains the Wireless Application Environment (WAE). It contains mobile device specifications and content development programming languages like WML and WMLScript 2. Session Layer: This layer contains Wireless Session Protocol (WSP). It provides fast connection suspension and reconnection. 3. Transaction Layer: This layer contains Wireless Transaction Protocol (WTP). It runs on top of UDP (User Datagram Protocol) and is a part of TCP/IP and offers transaction support. It provide a simplified protocol suitable for low bandwidth wireless stations. 4. Security Layer: This layer contains Wireless Transaction Layer Security (WTLS). It incorporates security features that are based upon the established Transport Layer Security (TSL) protocol standard. It offers data integrity, privacy and authentication. 5. Transport Layer: This layer contains Wireless Datagram Protocol. It presents consistent data format to higher layers of WAP protocol stack.Working mechanism of WAP  The user opens the mini-browser in a mobile device. He selects a website that he wants to view.  The mobile device sends the URL encoded request via network to a WAP gateway using WAP protocol.  The WAP gateway translates this WAP request into a conventional HTTP URL request and sends it over the internet.  The request reaches to a specified Web server and it processes the request just as it would have processed any other request and sends the response back to the mobile device through WAP gateway in WML file which can be seen in the micro-browser. Wireless Technologies Wireless technology refers to technology that allows us to communicate without using cables or wires. Wireless technology provides the ability to communicate between two or more entities over distances without the use of wires or cables of any sort. This includes communications using electromagnetic waves through the air. Wireless technology is usually more expensive, but it has provided the additional advantage of mobility, allowing the user to receive and transmit information while on the move. The major use of wireless technology has been in the area of broadcast communications like radio, television, and direct broadcast satellite. A single wireless transmitter can send signals to several hundreds of thousands of receivers as long as they all receive the same information. Today, wireless technology encompasses such diverse communication devices as garage-door openers, baby monitors, walkie-talkies, and cellular telephones, as well as transmission systems such as point-topoint microwave links, wireless Internet service, and satellite communications. Wireless keyboards and mice for computers, wireless speakers and headphones, and wireless smart sensors are now available on the market. The electromagnetic waves used in wireless technology includes waves like: radio waves, microwaves, infrared waves. These waves transmit data at different frequencies that do not interfere with each other. Frequency bands are either licensed or unlicensed. Licensed bands are owned by certain companies or facilities for specific purposes and cannot be used by anyone else. Unlicensed bands are free and any one can use them, subject to certain protocols. Some of the characteristics of wireless communications systems which make it attractive for users are:1. Mobility − A wireless communications system allows users to access information beyond their desk and conduct business from anywhere without having a wire connectivity. 2. Reachability − Wireless communication systems enable people to be stay connected and be reachable, regardless of the location they are operating from. 3. Simplicity − Wireless communication system are easy and fast to deploy in comparison of cabled network. Initial setup cost could be a bit high but other advantages overcome that high cost. 4. Maintainability − In a wireless system, you do not have to spend too much cost and time to maintain the network setup. 5. Roaming Services − Using a wireless network system, you can provide service anywhere any time including train, buses, airplanes etc. 6. New Services − Wireless communication systems provide various smart services like SMS and MMS. Different technologies used for data communication are:  ADSL  WiMAX  WLAN  WMAN  Wi-Fi Wireless Technologies  UMTS (3G)  LTE (4G)  NR (5G) ADSL (Asymmetric Digital Subscriber Line)  ADSL is a high-speed Internet access service that utilizes existing copper telephones lines to send and receive data at speeds that far exceed conventional dial-up modems.  ADSL uses standard telephone lines to transmit upstream and downstream data on a digital frequency, which sets these data streams apart from the analog signals telephones and fax machines use.  ADSL allows data stream speeds from 1.5 to 8 megabits per second (Mbps).  The "asymmetric" in ADSL refers to the fact that the downstream data rate, or the data coming to your computer from the Internet, is traveling faster than upstream data, or the data traveling from your computer to the Internet.  Upstream data rates are slower because Web page requests are fairly miniscule data strings that do not require much bandwidth to handle efficiently. Features:  Runs through the BT phone line network  High-quality, reliable broadband connection  Permits faster data transmission through a single connection  Allows internet access at the same time as making phone calls  Minimal installation costs and maintenanceAdvantages: Affordable, Large coverage area, does not affect your landline phone calls Disadvantages: Low speed, Distance-sensitive, Susceptible to electrical noise DSL (Digital Subscriber Line) DSL is a communications medium used to transfer digital signals over standard telephone lines. Along with cable Internet, DSL is one of the most popular ways ISPs provide broadband Internet access. Types of DSL: 1) ADSL - ADSL supports a range of asymmetric (higher downstream than upstream) data speeds that can reach up to 7Mbps downstream and 1.5Mbps upstream. ADSL can deliver simultaneous high-speed data and telephone service over the same line. 2) SDSL (Symmetric Digital Subscriber Line) - SDSL supports symmetric (equal downstream and upstream) data transmissions up to 1.54Mbps. 3) VDSL (Very High Bit-rate Digital Subscriber Line) - VDSL is the fastest of all DSL and provides transmission rates of 13-52Mbps downstream and 1.5-2.3Mbps upstream over a single copperpair wire, at a distance of 1,000-4,500 feet from the service provider's premises. 4) VDSL2 (Very High Bit-rate Digital Subscriber Line 2) - VDSL2 is faster than VDSL and provides transmission rates up to 100Mbps at longer distances. WiMAX  WiMAX stands for Worldwide Interoperability for Microwave Access.  It is an IP based Wireless Broadband Access Technology.  It is an alternative to wired broadband, such as DSL and cable modem.  It is a broadband wireless networks that are based on the IEEE 802.16 standard, which ensures compatibility and interoperability between broadband wireless access equipment.  It operates similar to Wi-Fi, but at higher speeds over greater distances and for a greater number of users. It has the ability to provide service even in areas that are difficult for wired infrastructure to reach.  It is expected to offer up to about 40Mbps capacity per wireless channel for both fixed and portable applications, depending on the particular technical configuration chosen enough to support hundreds of businesses with T-1 speed connectivity and thousands of residences with DSL speed connectivity.  It can support voice and video as well as Internet data. Nepal Telecom also provides WiMAX Service. It is available throughout the country within the tentative 2 km radius from the base station. It provides Internet speed of 256Kbps to 2Mbps. The service is provided in three options: USB Dongle, In Door Unit (IDU) and Out Door Unit (ODU). Benefits of using WiMAX 1. It can support high bandwidth solutions that is required for a full range of high-value multimedia services. 2. It can help service providers meet many of the challenges they face due to increasing customer demands without discarding their existing infrastructure investments as it can seamlessly interoperate across various network types.