Business Information Technology- Assignment
AJ-773
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Information Systems: A Manager’s Guide to Harnessing Technology V 3.0
By John Gallaugher
Chapter 14
A Manager’s Guide to the Internet and Telecommunications
Learning Objectives
Describe how the technologies of the Internet combine to answer these questions: What are you looking for? Where is it? And how do we get there?
Interpret a URL, understand what hosts and domains are, describe how domain registration works, describe cybersquatting, and give examples of conditions that constitute a valid and invalid domain-related trademark dispute.
Describe certain aspects of the Internet infrastructure that are fault-tolerant and support load balancing.
Discuss the role of hosts, domains, IP addresses, and the DNS in making the Internet work.
HOW THE INTERNET WORKS
Internet service provider (ISP): Organization or firm that provides access to the internet.
Connect to one another, exchanging traffic.
Ensure that messages can get to any other computer that’s online and willing to communicate.
Uniform Resource Locator (URL)
Protocol: Enables communication by defining the format of data and rules for exchange.
Hypertext transfer protocol: Application transfer protocol that allows Web browsers and Web servers to communicate with each other.
SMTP: Simple mail transfer protocol: server to hold e-mail.
FTP: Application transfer protocol that is used to copy files from one computer to another.
Identifies resources on the internet along with the application protocol
Anatomy of a web address
Application Transfer Protocol
Host name
Domain name (top-level domain)
Path
File
Case-sensitive
Hosts and Domain Names
Domain name: Represents an organization.
Hosts: Public services offered by that organization.
Load balancing: Distributing a computing or networking workload across multiple systems in order to avoid congestion and slow performance.
Fault tolerance: Systems that are capable of continuing operation even if a component fails.
None of these are case-sensitive.
Owning a Domain
One can register a domain name, paying for a renewable right to use that domain name.
Web hosting services: Firm that provides hardware and services to run the Web sites of others.
ICANN (Internet Corporation for Assigning Names and Numbers): Nonprofit organization responsible for managing the Internet’s domain and numbering.
Cybersquatting: Acquiring a domain name that refers to a firm, individual, product, or trademark, with the goal of exploiting it for financial gain.
Path Name and File Name
Paths map to a folder location where the file is stored on the server.
Hypertext markup language (HTML): Language used to compose Web pages.
Both are case sensitive
IP Address
Can be used to identify a user’s physical location.
NAT (network address translation): Conserves IP addresses by mapping devices on a private network to single Internet-connected devices that acts on their behalf.
Helps delay the impact of the IP address drought.
Value used to identify a device that is connected to the Internet
Domain Name Service (DNS)
Distributed database that looks up host and domain names and returns the actual IP address for them.
Nameservers: Find Web servers, e-mail servers, and more.
Cache: Temporary storage space used to speed computing tasks.
Internet directory service that allows devices and services to be named and discoverable
Domain Name Service (DNS)
Learning objectives
Understand the layers that make up the Internet and describe why each is important.
Discuss the benefits of Internet architecture in general and TCP/IP in particular.
Name applications that should use TCP and others that might use UDP.
Understand what a router does and the role these devices play in networking.
Conduct a traceroute and discuss the output, demonstrating how Internet interconnections work in getting messages from point to point.
Understand why mastery of Internet infrastructure is critical to modern finance and be able to discuss the risks in automated trading systems.
Describe VoIP, and contrast circuit versus packet switching, along with organizational benefits and limitations of each.
TCP/IP
TCP (Transmission control protocol): Works at both ends of internet communication to ensure a perfect copy of a message is sent.
Packets or datagrams: Unit of data forwarded by a network.
All internet transmissions are divided into packets.
IP (Internet protocol): Routing protocol that is in charge of forwarding packets on the internet.
Routers: Computing device that connects networks and exchanges data between them.
TCP/ip
Router
Router
Router
Router
Router
TCP
TCP
IP
Web page on a web server
Web page on a computer
TCP/IP
UDP (User datagram protocol): Operates instead of a TCP in applications where delivery speed is important and quality can be sacrificed.
VoIP (Voice over Internet protocol): Transmission technologies that enable voice communications to take place over the Internet and private packet-switched networks.
Router and Computer CONNECTIONS
Routers are connected wirelessly or by cables.
Copper cables with transmissions sent through via electricity.
Fiber-optic lines-glass lined cables that transmit light.
Peering: When separate ISPs link their networks to swap traffic on the Internet.
Takes place at neutral sites called Internet exchange points (IXPs).
Colocation Facility (Colo)
Provides a place where:
Gear from multiple firms can come together.
Peering of Internet traffic can take place.
Equipment connecting in colos:
High-speed lines from ISPs.
Telecom lines from large private data centers.
Servers hosted in a colo to be closer to high-speed Internet connections.
Traceroute
Repeatedly sends a cluster of three packets starting at the first router connected to a computer.
Builds out the path that packets take to their destination.
Built into all major desktop operating systems.
Several Web sites will run it between locations.
Neat way to explore how the Internet works.
Learning Objectives
Understand the last-mile problem and be able to discuss the pros and cons of various broadband technologies, including DSL, cable, fiber, and various wireless offerings.
Describe 3G and 4G systems, listing major technologies and their backers.
Understand the issue of Net neutrality and put forth arguments supporting or criticizing the concept.
Last Mile
Internet backbone: High-speed data lines that interconnect and collectively form the core of the Internet.
Amdahl’s Law: System’s speed is determined by its slowest component.
Last mile problem: Internet connections are the slowest part of the network.
Broadband: High-speed Internet connections.
Bandwidth: Network transmission speeds that are expressed in some form of bits per second (bps).
Refers to Technologies that connect end users to the Internet
Cable broadband
Uses thick copper wire to offer broadband access.
Coaxial cable: Insulated copper cable used by television providers.
Has shielding that reduces electrical interference.
Allows cable signals to travel longer distances without degrading and with less chance of interference.
Limitation: Requires customers to share bandwidth with neighbors.
Digital Subscriber Line (DSL)
Broadband technology that uses the wires of a local telephone network.
Speeds vary depending on the technology deployed.
Limitation: uses standard copper telephone wiring that lacks the shielding used by cable.
Broadband over power line technology has been available for years.
Deployments are few because it is considered to be pricier and less practical than alternatives.
Fiber to the Home (FTTH)
Broadband service provided via light-transmitting fiber-optic cables.
Fastest last-mile technology and works easily over long distances.
Limitations:
Need to build fiber infrastructure from scratch.
Cost of building is enormous.
Wireless
Mobile wireless service from cell phone access providers is delivered via cell towers.
Providers require a wireless spectrum.
Wireless spectrum: electromagnetic frequencies used for communication.
Most mobile cell phone services have to license spectrum.
3G
Offer access speeds usually less than 2 Mbps.
3G standards can be narrowed down to:
GSM: Global system for mobile communications
CDMA: Code division multiple access
3G is being replaced by high-bandwidth 4G.
4g
The winner in 4G technologies is:
LTE - Long Term Evolution.
Download speed is 5 to 18 Mbps and upload speed is reaching 2 to 9 Mbps.
Some tests showed download speeds as high as 50 Mbps and upload speeds as high as 25 Mbps.
Satellite Wireless
Terrestrial wireless: provided by earth-bound base stations like cell phone towers.
Possible via satellite.
First residential satellite services were only used for downloads.
Later some services were based on satellites in geosynchronous earth orbit (GEO).
O3b hopes to provide fiber-quality wireless service to more than 150 countries, specifically targeting underserved nations.
Wi-Fi and Other Hotspots
Wi-Fi: Wireless local-area networking devices
Stands for wireless fidelity.
Wi-Fi antennas are built into their chipsets.
To connect to the Internet, a device needs to be within range of a base station or hotspot.
Wi-Fi base stations used in the home are usually bought by end users.
They are then connected to a cable, DSL, or fiber provider.
Net Neutrality
Access providers have wanted to offer varying coverage, depending on the service used and bandwidth consumed.
Internet content providers worry that without strong neutrality rules, ISPs may block content or favor their own offerings above rivals.
If network providers move away from flat-rate pricing toward usage-based pricing, this may limit innovation.
Principle that all Internet traffic should be treated equally
