03 Ec ECommerce Infrastructure

INFO 3435 eCommerce

Alexander Nikov

3. eCommerce Infrastructure: Internet, web and mobile platform

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Teaching Objectives

• Discuss the origins of the Internet.• Identify the key technology concepts behind the Internet.• Describe the role of Internet protocols and utility programs.• Explain the current structure of the Internet.• Explain the limitations of today’s Internet.• Describe the potential capabilities of Internet II.• Explain how the World Wide Web works.• Describe how Internet and Web features and services

support eCommerce.• Explain the impact of mCommerce applications

Outline

1.The Internet: Technology Background

2. The Internet Today

3. The Future Internet Infrastructure

4. The Web

5. The Internet and the Web: Features and services

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The Internet: Technology Background• Internet

– Interconnected network of thousands of networks and millions of computers

– Links businesses, educational institutions, government agencies, and individuals

• World Wide Web (Web)– One of the Internet’s most popular services

– Provides access to around billions, possibly trillions, of Web pages

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Trends in eCommerce infrastructure 2013-2014eCommerce infrastructure

E-commerce applicationWeb application

World Wide Web

Internet

Data communication network

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1.1. The Evolution of the Internet1961—The Present

• Innovation Phase, 1964–1974

– Creation of fundamental building blocks• Institutionalization Phase, 1975–1994

– Large institutions provide funding and legitimization

• Commercialization Phase,1995–present

– Private corporations take over, expand Internet backbone and local service

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1.2. The Internet: Key Technology Concepts

• Defined by Federal Networking Commission as network that:

– Uses IP addressing

– Supports TCP/IP

– Provides services to users, in manner similar to telephone system

• Three important concepts:1. Packet switching

2. TCP/IP communications protocol

3. Client/server computing

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1.2.1. Packet Switching

• Slices digital messages into packets

• Sends packets along different communication paths as they become available

• Reassembles packets once they arrive at destination

• Uses routers – Special purpose computers that interconnect the computer networks that make

up the Internet and route packets– Routing algorithms ensure packets take the best available path toward their

destination

• Less expensive, wasteful than circuit-switching

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Packet SwitchingFigure 3.3, Page 119

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Packet switching

• Objective:– Efficiently utilize

bandwidth• Process

– Break message into packets

– Transmit packets independently

– Multiple messages share line

– Reassemble message at receiving end

Packet A1 Packet A2 Packet A3

Message A

Packet A1 Packet A2 Packet A3

Message A

Packet A3 Packet Packet

Packet Packet A2 Packet

Open Packet Packet

Packet A1 Packet Open

Packet Packet Open

Packet Packet Packet

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A message’s packets can follow different paths

Router 3

Router 4

Router 6

Router 7 Router 9

Router 8Router 1

Router 2

Router 4 Router 5

Router 5Router 5

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Packets and Internet Protocols

• Protocols are pieces of software that run on every node or computer and allow every pair of computers to communicate directly without having to know much about each other, except for the IP address

• Protocols govern communication between peer processes on different systems

• Differing client browser and Web server

• Protocols used in connection with the Internet include many functions and the TCP/IP protocol suite

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1.2.2 TCP/IP

• Transmission Control Protocol (TCP): – Establishes connections between sending and

receiving Web computers– Handles assembly of packets at point of

transmission, and reassembly at receiving end

• Internet Protocol (IP): – Provides the Internet’s addressing scheme

• Four TCP/IP Layers1. Network Interface Layer2. Internet Layer3. Transport Layer4. Application Layer

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The TCP/IP Architecture and Protocol Suite

Figure 3.4, Page 121

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The TCP/IP model.

Application layer

Transport layer

Internet layer

Network access layer

The top two layers work withthe message.

The bottom two layers work withpackets and control the network.

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OSI Reference Model• Application Layer• Presentation Layer• Session Layer• Transport Layer• Network (Internet) Layer• Data Link Layer• Physical Layer

• A seven-layer model that defines the basic network functions

• Each layer handles a different portion of the communications process with specific network functions

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ISO 7-layer Model

Layer 7Application

Layer 6Presentation

Layer 5Session

Layer 4Transport

Layer 3Network

Layer 2Data Link

Level 1Physical

Layer 7Application

Layer 6Presentation

Layer 5Session

Layer 4Transport

Layer 3Network

Layer 2Data Link

Level 1Physical

Node A Node B

Data translationMIME, encryption, etc.

User applicationsFTP, email, browser, etc.

End-to-End controlError correction (TCP)

Link managementMAC, physical addressing

Session managementDialog management, security

Manages data transferMessage routing (IP)

Physical hardwareMedia, signal transmission

Messages

Messages

Messages

Messages

Packets

Frames

Bits on physical medium

The Open Systems Interconnect (OSI) model.

OSI layer Responsibilities

Application Provides a logical link between an application program andthe lower-level protocols.

Presentation Performs necessary data representation and/or syntaxconversions; e.g., encryption/decryption.

Session Establishes, maintains, and terminates a connection.

Transport Breaks the message into packets. Ensures error free, end-to-end delivery of the complete message.

Network Determines the best route for sending a packet from thesource node to the destination node.

Data-link Formats a packet for transmission to the next node.

Physical Interfaces with the physical communication medium.

The top four layers work with the message.

The bottom three layers work with packets and control the network.

A blueprint.

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Application Layer

• Communicates with the actual application in use• Standards at the application layer specify how two application programs

should communicate– The main standard hypertext transfer protocol (HTTP)– Hypertext markup language (HTML) is a standard set of codes

representing text or graphics• The application layer is where the user begins to do something useful• Simple network management protocol (SNMP) is a protocol that controls

network devices at the application layer• Domain naming service (DNS) is software that converts IP addresses

into easy-to-remember names for the user

The application layer protocols support application programs.

Application layer

Transport layer

Internet layer


FTP

POP

telnet

SNMP

http SMTP

Other DNS

From application program

To transport layer

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Some common application layer protocols.

AcronymFTP

HTTP

POP

SMTP

SNMP

Telnet

Hypertext transfer protocol

File transfer protocolName

Post office protocol

Simple mail transferprotocolSimple networkmanagement protocolTerminal emulationprotocol

Send an e-mail message from the originator'scomputer to the recipient's mail server.

FunctionDownload a file from or upload a file toanother computer.Request and download a web page. HTTP isthe standard Web surfing protocol.Deliver accumulated mail from a mail serverto the recipient's computer.

Monitor the activity of a network's hardwareand software components.Log into a remote computer. System operatorsuse telnet to remotely control a server.

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The application layer FTP protocol adds a header.

FTP requestFTPheader

FTP requestApplication program

Application layer

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Presentation and Session Layers

• Presentation Layer – The network’s translator– Converts data into a format for network

transmission and converts incoming data into a format the receiving application can understand

• Session Layer– Facilitates a “session” between two parties to

communicate across a network– Keeps track of the status of the exchange and

ensures that only designated parties are allowed to participate

– Enforces security protocols

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Transport Layer

• Manages the transmission or flow of data between two computers or across a network

• Manages the data flow is by segmenting data into multiple packets

• Acknowledges successful transmissions and requests retransmission if packets are damaged or arrive in error

• Breaks the connection when transmission ends

• Standard for the transport layer is the transmission control protocol (TCP)

The next layer down is the transport layer.

Application layer

Transport layer

Internet layer


TCPOther

transportprotocol

From application layer

To Internet layer

The transport layer usually uses the TCP protocol.

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TCP adds its own header.

TCPheader FTP requestFTP

header



Application layer

Transport layer (each packet)

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Network (Internet) Layer

• Routes messages across multiple nodes

• Handles network congestion

• Standard for routing packets is the Internet Protocol (IP)

• Resends lost packets automatically

• Defines how data are subdivided into packets

The Internet layer uses the Internet protocol (IP)

Application layer

Transport layer

Internet layer


IP

From transport layer

To network access layer

ARP

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IP adds its own header.


TCPheader

IPheader


header



Application layer


Internet layer(each packet)

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Data Link Layer

• The “basement” of the Internet

• Messages at the data link layer are called data frames the basic unit of Internet traffic

• Another way of sending packets is over an Ethernet– Framing and error detection are handled automatically by

Ethernet hardware– Ethernet broadcasts a message to all the computers

linked to it, but only the computer with the right address broadcasts an answer

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Physical Layer

• Lowest layer in the journey of a message from source to destination

• Converts bits into signals for outgoing messages and signals into bits for incoming messages

The network access layer adds another header.


TCPheader

IPheader


header



Application layer


Internet layer(each packet)


TCPheader

IPheader

Networkheader

Network accesslayer

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1.2.3 Internet (IP) Addresses• A Web site’s address includes the name of the host computer’s link the

Web site resides on

• Each host is identified by a unique host number (called an IP address) and by a name that is easier to remember than the number

• IPv4:– 32-bit number – Four sets of separate numbers marked off by periods

• 201.61.186.227• Class C address: Network identified by first three sets, computer

identified by last set

• IPv6:– 128-bit addresses, able to handle up to 1 quadrillion addresses

(IPv4 can only handle 4 billion)

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IP Address Arithmetic

• An IP address consists of 32 binary digits or bits (zeros and ones)

• Divide the 32 bits into 4 groups of 8 bits called a byte, or octet

• Each octet represents a decimal value from 0 through 255

• Write the four decimal values separated by dots

• 191.170.64.12 - computer friendly, but not human friendly

• Every host on the Internet has a host number

1.2.4 Domain Names, DNS, and URLs

• Domain Name– IP address expressed in natural language

• Domain Name System (DNS)– Allows numeric IP addresses to be expressed in natural

language

• Uniform Resource Locator (URL)– Address used by Web browser to identify location of content on

the Web– E.g., http://www.azimuth-interactive.com/flash_test

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How to Pick a Domain Name

• Pointer for picking domain names

– If you sell bricks, pick a domain name containing a word like brick– Consider name length and ease of remembering the name– Hyphens to force search engines to see keywords in your domain

name– Make sure the domain name is easy for Web users to remember and

find– The domain name should suggest the nature of your product or

service– The domain name should serve as a trademark– The domain name should be free of legal conflicts

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How to Register a Domain Name

• Check if the domain name you propose has been taken

• www.FasterWhois.com

• One of the most popular and reliable registration sites is www.internic.net/alpha.html

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Pieces of the Internet puzzle: names and addresses

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Host Naming

• A host name is an Internet address consisting of text labels separated by dots

• Host name is people friendly

• Host names used instead of IP addresses or host numbers

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Networks and Numbers

• Host number divided into two parts– Network part - 2 octets– Local part - 2 octets

University of Virginia host number191 . 170 . 64 . 12

network localpart part

– All UVa addresses begin with 191 . 170– 64 identifies a subnet at UVa– 12 is the machine on the subnet

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Zones and Domain Names

• An Internet name is decoded from right to left

• Zone name is the last (rightmost) part of a domain name preceded by a dot, specifying the type of domain name

• Zones are classified in two ways:– Three-letter zone names– Two-letter zone names

• Domain name is a Web address that contains two or more word groups separated by periods

• www.virginia.com => domain name.com => zone

A domain name consists of two to four words separated by dots.

sbaserver1.sba.muohio.edu

Server within SBA sub-domain

SBA sub-domain

Miami University domain

Top-level domain

Domain: a set of nodes administered as a unit.

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The parts of a domain name are structured as a hierarchy.

edu

134com org

muohio

134.53

sba

134.53.40

cas

134.53.54

sbaserver1

134.53.40.2

sbadata

134.53.40.4

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Top-level domain names.

Domain Signifies Domain Signifies aero Air-transport industry au Australia biz Business organization br Brazil com US commercial ca Canada coop Coooeratives cn China edu US educational de Germany info Unrestricted fi Finland gov US government fr France mil US military gb Great Britian museum Museums in India name Individuals it Italy net US network jp Japan org US non-profit ru Russia pro Professionals za South Africa

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Common Geographical Two-Letter Zone Names

An IP address.

134.53.40.2Server within SBA domain

SBA domainMiami University domain

Top-level domain

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A domain name and an IP address convey the same information.

• Physical transmission requires IP address• Domain name system converts domain name to

equivalent IP address

sbaserver1.sba.muohio.edu 134.53.40.2

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Well-known port assignments

Port Used for: 5 RJE (Remote Job Entry) 20 FTP (File Transfer Protocol) data 21 FTP (File Transfer Protocol) control 23 TELNET (Terminal emulator) 25 SMTP (Simple Mail Transfer Protocol) 79 FINGER (Given e-mail address, identify user) 80 HTTP (Hypertext Transfer Protocol) 110 POP3 (Post Office Protocol, Version 3) 119 NNTP (Network News Transfer Protocol)

Port: endpoint of a logical connection

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TCP/IP address translation

• DNS– Domain name to IP

• ARP– IP to MAC address

• Map logical domain name to physical device.

• MAC address– Final node– Not directly on Internet

Domain NameSystem (DNS)

IP address

AddressResolution

Protocol (ARP)

MAC address

domain name

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Routing Internet Messages: TCP/IP and Packet Switching


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1.2.5. Client/Server Computing

• Powerful personal computers (clients) connected in network with one or more servers

• Servers perform common functions for the clients

– Storing files

– Software applications,

– Access to printers, etc.

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Client/Server Basics

• Client/server architecture is a versatile, message-based, modular infrastructure intended to improve usability, flexibility, interoperability, and scalability as compared to centralized, mainframe, time-sharing computing

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Client/Server Networks

• A server is simply a special-purpose computer designed to address a client’s requests

• A client is any computer or workstation connected to the server within a network

• All programs or applications reside on the server

• The client downloads software and/or data from the server

• When the client finishes data may be uploaded back to the server

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Client/Server Network

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Pros and Cons of Client/Server NetworkThe New Client: The Mobile Platform

• Primary Internet access is now through:– Tablets

• Supplementing PCs for mobile situations– Smartphones

• Disruptive technology: – Shift in processors, operating systems

• 38% of all cell phones

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Cloud Computing

• Firms and individuals obtain computing power and software over Internet

• Public, private, and hybrid clouds• Radically reduces costs of:

– Building and operating Web sites– Infrastructure, IT support– Hardware, software

• Risks: Organizations become dependent on outside providers

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1.3 Other Internet Protocols and Utility Programs

• Internet protocols– HTTP– E-mail: SMTP, POP3, IMAP– FTP, Telnet, SSL/TLS

• Utility programs– Ping– Tracert

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Tracing the route a message takes on the InternetOutline

1. The Internet: Technology Background

2.The Internet Today


4. The Web


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The Internet Today

• Internet growth has boomed without disruption because it is based on:– Client/server computing model– Hourglass, layered architecture

• Network Technology Substrate• Transport Services and Representation Standards• Middleware Services• Applications

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The Hourglass Model of the Internet


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SOURCE: Adapted from Computer Science and Telecommunications Board (CSTB), 2000.

2.1 Internet backbone

• Backbone: – High-bandwidth fiber-optic cable networks – Private networks owned by a variety of NSPs– Bandwidth: 155 Mbps–2.5 Gbps– Built-in redundancy

• IXPs: Hubs where backbones intersect with regional and local networks, and backbone owners connect with one another

• CANs: LANs operating within a single organization that leases Internet access directly from regional or national carrier

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Internet Network ArchitectureFigure 3.12, Page 131

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Internet Basics

• The Internet is a network of networks– Network is any-to-any communications

• Each station on the network has a unique address (much like a phone number) called an IP address

• Routers and switches forward traffic between network segments

• Protocols are rules that govern the way a network operates:– How data travel in packets– How electrical signals represent data on a network cable

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Network Components

• Network Interface Card– A card installed in a slot in the PC to allow communication between

the PC and other PCs in the LAN and beyond– To communicate over a telephone line the PC needs a modem, a

device that converts digital signals into analog format for outgoing transmission and converts incoming messages from analog to digital format for computer processing

• Hubs and Switches– Hub is a piece of hardware that operates at the OSI physical layer

and acts as a connecting point– Switch is a piece of hardware that offers a direct connection to a

particular PC

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Network Components (cont'd)

• Routers– A piece of hardware that operates at the OSI Internet layer, linking

the network into little chunks called network segments– Usually “intelligent” and evaluate the network traffic and can stop

local traffic from entering and causing congestion – Make intelligent path choices– Filter out packets that need not be received– Expensive and difficult to operate

• Gateways– A special-purpose computer that allows communication between

dissimilar systems on the network

2.2 Internet Service Providers (ISPs)

• Provide lowest level of service to individuals, small businesses, some institutions

• Types of service– Narrowband (dial-up)

– Broadband• Digital Subscriber Line (DSL)

• Cable modem

• T1 and T3

• Satellite

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ISP service levels and bandwidth choices

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Time to download a 10-MB file by type of Internet service

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2.3 Intranets and Extranets

• Intranet

– TCP/IP network located within a single organization for communications and processing

• Extranet

– Formed when firms permit outsiders to access their internal TCP/IP networks

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What Is an Intranet?• An intranet delivers collaboration and coordination to

employees around the clock– Communication system designed by technical staff– A network of people, not of wired machines– Focus is the message, not the media

• An organization-wide software and information distribution system that applies Internet technology and standards to a closed network within the organization

• Normally runs in a client/server environment and a local area network configuration

• Separated from other networks by firewalls, a means of preventing unauthorized access to the company’s internal data or leaks of sensitive company information

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Applications - Human Resources

• Employee handbook

• Benefits information

• Employee surveys

• Internal/external recruiting

• Candidate screening

• Organization charts

• Newsletters

• Company calendar

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Applications - Sales and Marketing

• Product information

• Market research

• Prospecting

• Managing sales contacts

• Sales training

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Applications - Accounting and Finance

• Financial reports

• Expense reports

• Accounts receivable/payable processing

• Asset management

• Policies and procedures

• Payroll

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Applications - Manufacturing and Operations

• Inventory control

• Production schedules

• Quality assurance

• Part order/requisition system

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Other Applications for Intranets

• Real-time broadcasting of news, including medical information.

• Document management to minimize unnecessary paperwork and waste of paper.

• Customized application modules like a travel or document library.

• Complete e-mail for interoffice and intraoffice communication.

• Internal company office circulars can be routed electronically.

• Bulletin board service.

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Other Applications for Intranets (cont’d)

• Real-time chat service that electronically logs all data for record keeping.

• Complete company staff, operations, and organizational chart directories.

• Channel for confidential exchange of data for electronic funds transfers (EFTs) and checks.

• A daily to-do list and assignments from a central desk to all connected desks.

• Foreign news and financial data broadcasting (running ticker) from direct feeds.

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Does Every Company Need an Intranet?

• A company needs an intranet for the following reasons:

– When it has a large pool of information to share among hundreds of employees

– Intranets are cheap, robust, and fast. Any employee with access to an intranet can disseminate and publish information

– Intranets operate across platforms– Information is available 24/7 to all employees at the click of a

mouse– Information available on an intranet can be updated quickly

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Extranets and SCM• Intranets are localized within a firm and move data quicker

than the more widely distributed extranets• Extranets are already the backbone of the e-business

future• Extranet designers at each participating company must

collaborate to make sure there is a common interface with the company they are dealing with

• The overall connectivity represents supply chain management

• Extranet-SCM and Enterprise Resource Planning (ERP)– ERP facilitates integration of company-wide information systems

with the potential to go across companies– The Internet allows linking the Web sites to back-end systems like

ERP, offering connections to a host of external parties like vendors and suppliers

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Basic Extranet Layout 2.4 Who Governs the Internet?• Organizations that influence Internet and monitor its

operations include:– Internet Corporation for Assigned Names and

Numbers (ICANN)– Internet Assigned Numbers Authority (IANA)– Internet Engineering Task Force (IETF)– Internet Research Task Force (IRTF)– Internet Engineering Steering Group (IESG)– Internet Architecture Board (IAB)– Internet Society (ISOC)– Internet Governance Forum (IGF)– World Wide Web Consortium (W3C)– Internet Network Operators Groups (NOGs)

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Limitations of current Internet

• Bandwidth limitations– Slow peak-hour service

• Quality of service limitations– Latency

• Network architecture limitations– Identical requests are processed individually

• Wired Internet– Copper and expensive fiber-optic cables

Outline



3.The Future Internet Infrastructure

4. The Web


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Internet2 Project

• Limitations of current Internet

– Bandwidth limitations

– Quality of service limitations• Latency• “Best effort” QOS

– Network architecture limitations

– Language development limitations• HTML

– Wired Internet limitations

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The Internet2® Project

• Consortium of 440+ institutions collaborating to facilitate revolutionary Internet technologies

• Primary goals:– Create leading-edge very-high speed network for

national research community– Enable revolutionary Internet applications– Distributed and collaborative computing environments

for sciences, health, arts, and humanities initiatives

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Internet2 100 GB networkThe First Mile and the Last Mile

• GENI Initiative– Proposed by NSF to develop new core functionality

for Internet

• Most significant private initiatives– Fiber optic trunk-line bandwidth

• First mile– Wireless Internet services

• Last mile

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Fiber Optics and the Bandwidth Explosion in the First Mile

• “First mile”: Backbone Internet services that carry bulk traffic over long distances

• Fiber-optic cable: hundreds of glass strands that use light to transmit data– Faster speeds and greater bandwidth– Thinner, lighter cables– Less interference– Better data security

• Substantial investments in fiber optic by telecommunications firms in last decade– Enable integrated phone, broadband access, video

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Communication requires five elements.

• Message– Information/content

• Transmitter– Source or sender

• Medium– Path or pipe

• Receiver– Sink or destination

Transmitter ReceiverMediumMessage

Protocol: a set of rules fortransmitting a message.

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Media Types

• Cable– Physical wire– Twisted pair, coaxial, fiber optic

• Wireless– No physical wire– Cellular, digital cellular, satellite

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Connectivity

• Ability to operate over a connection– Physical – medium– Logical – protocol

• Line types– Baseband – one signal at a time– Broadband – simultaneous signals in parallel

• Example – cable TV

– Cable can be baseband or broadband– Wireless can be baseband or broadband

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Plain old telephone service.

• The cloud is a common way to visualize an infrastructure

Central office

Long distanceconnection

Source

Central office

Destination

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Network Cable Types

• Network connectivity means:– Speed of data transfer– Network size– Ease of installation

• There are three types of cable– Twisted pair– Optical fiber– Coaxial– Wireless technology

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Twisted-Pair Cable

• Two pairs of insulated wires twisted around each other, even enclosed in a plastic sheath

• The most commonly used type of networking cable in theUnited States

• Originally used to connect a telephone to a wall jack

• Least expensive cable medium

• Shielded and unshielded twisted pair– Unshielded twisted-pair (UTP) cabling does not have shielding against

electrical interference– Shielded twisted-pair (STP) cabling has an electrically grounded woven

copper mesh or aluminum foil wrapped around each twisted pair and another metal mesh wrapped around a multiple bundle of wires to reduce electromagnetic interference

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Fiber-Optic Cable

• Uses light rather than voltage to carry data

• Fiber enables digitized light signals to be transmitted more than 60 miles without being amplified

• Outperforms copper and coaxial media with fewer transmission losses, lower interference, and higher bandwidth

• Drawbacks are:– It is the most expensive of all network media types– Each segment that transmits incoming and receiving data must

contain an incoming cable and an outgoing cable– It requires highly skilled installers and special connectors

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Optical Fiber

Source: Adapted from Panko, Raymond, Business Data Communications and Networking (3rd ed.), Upper Saddle River, NJ: Prentice-Hall, 2001, p. 278.

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Coaxial Cable

• An early version of the way computers were connected to a network

• The cable in cable TV

• Has a copper core that is much thicker than twisted-pair cable, so it allows higher data transmission rates over long distances

• Transmits up to 10 Mbps for a distance of up to 500 meters

• Main drawback is its inflexibility and low security

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The Last Mile: Mobile Internet Access

• “Last mile”: From Internet backbone to user’s computer, smartphone, and so on

• Two different basic types of wireless Internet access:– Telephone-based (mobile phones, smartphones)– Wireless local area network (WLAN)-based

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Wireless Technology

• Data communication without physical attachments

• Three types of wireless data transmission technology:

– Microwave transmission is used to connect LANs in separate buildings that must be within the line of sight of each other

– Radio technology by radio frequency with no distance limitations– Infrared transmission operates at frequencies approaching the

speed of light

Wireless communication.

• Both POTS and wireless use the same long distance infrastructure.

Telephone

A lice

Mobile switching center

M obile switching center

Long distancenetwork

Trunk

Trunk

Radio tow er

HubBase station

Telephone

Bob

Radio tow er

HubBase station

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POTS and wireless are alternative access paths to the long distance infrastructure.

• Cable and satellite Internet services use the same long distance lines.

POTS Wireless service

Long distance infrastructure

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High-speed optical bandwidth standards

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The Last Mile Problem

• Speed disparity– Local telephone line – 56 Kbps– Long-distance line – 40+ Mbps

• Alternatives– Satellite – 400 Kbps– DSL – 1.44 Mbps– Cable – 2-10 Mbps– Fiber optic cable – up to 10 Gbps

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Wireless Internet Access Telephone Technologies

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Wireless Internet Access Network Technologies

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Wi-Fi NetworksFigure 3.16, Page 158

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Benefits of Internet access networks

• IP multicasting: – Enables efficient delivery of data to many locations on a network

• Latency solutions: – diffserv (differentiated quality of service)

• Assigns different levels of priority to packets depending on type of data being transmitted

• Guaranteed service levels and lower error rates – Ability to purchase right to move data through network at guaranteed

speed in return for higher fee

• Declining costs

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Outline




4.The Web


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Development of the Web

• 1989–1991: Web invented – Tim Berners-Lee at CERN– HTML, HTTP, Web server, Web browser

• 1993: Mosaic Web browser w/GUI– Andreesen and others at NCSA – Runs on Windows, Macintosh, or Unix

• 1994: Netscape Navigator, first commercial Web browser– Andreessen, Jim Clark

• 1995: Microsoft Internet Explorer

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4.1 Hypertext

• Text formatted with embedded links

– Links connect documents to one another, and to other objects such as sound, video, or animation files

• Uses Hypertext Transfer Protocol (HTTP) and URLs to locate resources on the Web

– Example URL

http://megacorp.com/content/features/082602.html

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4.2 Markup Languages

• Generalized Markup Language (GML)—1960s• Standard Generalized Markup Language (SGML)—early

GML,1986

• Hypertext Markup Language (HTML)– Fixed set of predefined markup “tags” used to format text– Controls look and feel of Web pages

– HTML5 the newest version

• eXtensible Markup Language (XML)– New markup language specification developed by W3C– Designed to describe data and information– Tags used are defined by user

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4.3 Web Servers and Clients

• Web server software: – Enables a computer to deliver Web pages to clients on networks that request this

service by sending an HTTP request– Apache and Microsoft IIS– Basic capabilities: security services, FTP, search engine, data capture

• Web server – Can refer to Web server software or physical server– Specialized servers: database servers, ad servers, etc.

• Web client: – Any computing device attached to the Internet that is capable of making HTTP

requests and displaying HTML pages

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4.4 Web Browsers

• Primary purpose to display Web pages

• Google’s Chrome (62%), Firefox (24%), and Internet Explorer (8%) dominate the market

• Other browsers include:– Safari (for Apple) 4%– Opera 2%

Source: http://www.w3schools.com/browsers/browsers_stats.asp, 29 Jan 2015

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Outline




4. The Web

5.The Internet and the Web: Features and services

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The Internet and Web: Features

• Internet and Web features on which the foundations of e-commerce are built include:– E-mail– Instant messaging– Search engines– Intelligent agents (bots)– Online forums and chat– Streaming media– Cookies

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5.1 E-mail

Most used application of the Internet Uses series of protocols for transferring messages

with text and attachments (images, sound, video clips, etc.,) from one Internet user to another

Instant Messaging Displays words typed on a computer almost

instantly, and recipients can then respond immediately in the same wayAdvanced IM systems include voice/video chat

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E-mail and the Intranet• E-mail is what intranets are best known for• 4.1 billion email accounts worldwide

(Source: technology market research firm The Radicati Group 2015)

• E-mail is becoming smarter: It now can direct specific messages to defined folders and be a place to check voice, text, and fax messages

• Intranets inherit Simple Mail Transport Protocol (SMTP) from the TCP/IP suite to operate e-mail

• E-mail is a potential threat for employers– Confidentiality breaches– Legal liability– Lost productivity– Damage to company reputation

• Important for a firm to create an e-mail usage policy and make sure the policy is actually implemented

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Spamming and Appropriate E-mail Use

• Spamming is sending unwanted advertisements or literature through e-mail or the Internet

• Companies have been overwhelmed by e-mail traffic, and spam is out of control

• Spot checks are no longer adequate

• Trend is more toward systematic monitoring of e-mail traffic using content-monitoring software

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Spamming and Appropriate E-mail Use (Cont’d)

• Spamming is nearly impossible to eliminate, but solutions exist:

– Blacklist the sender; obtain a spammer’s address and block any e-mail from that address

– Accept e-mail only from a list of approved addresses– Look for signs of spam– Use anti-spam software

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Personal Guidelines to Avoid Spam

• Stop giving away your e-mail address

• Do not “unsubscribe,” it only confirms your e-mail address is real

• Write to the Direct Marketing Association and credit bureaus

• Contact your credit card companies, credit union, and mortgage companies and tell them not to release your name, address and similar data

• Contact all organizations you belong to, schools, magazines you subscribe to, airline frequent flyer programs, your long-distance telephone carrier, and just about anyone who sends you a bill

• As a last resort, contact your phone company and change your listing in the phone book, or simply list your name with no address

5.2 Instant Messaging

• Sometimes the rapid response of e-mail is not fast enough

• Instant messaging is one alternative medium

• IM is an electronic communication system that involves immediate correspondence between two or more users who are all online simultaneously

• Displays words typed on a computer almost instantly, and recipients can then respond immediately in the same way

• Different proprietary systems offered by AOL, MSN, Yahoo, and Google

• Meebo, Digsby: allow users to communicate across platforms

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5.3 Search Engines

• Identify Web pages that match queries based on one or more techniques– Keyword indexes, page ranking

• Also serve as:– Shopping tools– Advertising vehicles (search engine marketing)– Tool within e-commerce sites

• Outside of e-mail, most commonly used Internet activity

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Top US Search Engines for 2014

How Google Works

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Figure 3.22, Page 180 5.4 Online Forums and Streaming Media

• Online forums: – Enable Internet users to communicate with one another,

although not in real time– Members visit online forum to check for new posts

• Streaming Media– Enables music, video, and other large files to be sent to

users in chunks so that the file can play uninterrupted– Allows users to begin playing media files before file is

fully downloaded

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5.5 Cookies

• Small text files deposited by Web site on user’s computer to store information about user, accessed when user next visits Web site

• Can help personalize Web site experience

• Can pose privacy threat

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5.6 Web 2.0 Features and Services

• Online Social Networks– Services that support communication among networks of

friends, peers• Blogs

– Personal Web page of chronological entries• Really Simple Syndication (RSS)

– Program that allows users to have digital content automatically sent to their computers over the Internet

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Web 2.0 Features and Services

• Podcasting

– Audio presentation stored as an audio file and available for download from Web

• Wikis

– Allows user to easily add and edit content on Web page

• New music and video services

– Videocasts– Digital video on demand

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Web 2.0 Features and Services

• Internet telephony (VoIP)– Voice over Internet Protocol (VoIP) uses Internet to

transmit voice communication• Video conferencing, video chatting, and telepresence• Online software and Web services

– Web apps, widgets, and gadgets

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Intelligent Personal Assistants

• Software that interacts with the user through voice commands

• Features– Natural language; conversational interface– Situational awareness– Interpret voice commands to interact with various

Web services• Examples: Siri, Google Now

Mobile Apps

• Use of mobile apps has exploded– Almost 75% of online shoppers are mobile shoppers

as well

• Increased use/purchasing from tablets• Platforms

– iPhone/iPad (iOS), Android, Blackberry

• App marketplaces – Google Play, Apple’s App Store, RIM’s App World,

Windows Phone Marketplace

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03 Ec ECommerce Infrastructure

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