e-commerce and information technology in hospitality and tourism chapter 3 connecting to the world...
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E-commerce and Information Technology in Hospitality and
Tourism
Chapter 3Connecting to the World
Copyright 2004 by Zongqing Zhou, PhD
Niagara University
3.1 Establishing a Standard Connection
• To connect to the Internet via telephone line you will need four basic things:
• A computer
• A modem
• An internet Service Provider
• A browser
Figure 3.1
Analog data Modulator
Analog transmission
(public telephone network)
Analog transmission
(public telephone network)
Digital data
Digital data
Digital transmitter
Modem
Digital transmission
(Digital data lines or local area
network)
Modem• Modem comes from
• Modulator• Demodulator
• A modem is an electronic device for converting between digital data from a computer or an audio signal suitable for transmission over telephone lines.
• The speed of data transmission is measured in bits per second, kilobits per second or in bauds.
Modem (cont.)
• A modems most common speeds are• 28,800• 36,000• 56,000
• Modems• Internal• External
ISP and OSP
• ISP• Once connected you are directly connected to the
Internet; it has no control over what you can access on the Internet.
• Most important factors when choosing an ISP:• Local phone number• Other features
−Speed−Features−Pricing−Reliability
ISP and OSP
• OSP
• You are connected to the Internet through OSP’s server
• OSP tends to offer its own programs which are screened and filtered through your service provider.
3.2 Alternative Connections
• Broadband communications channels- high-speed internet access.• ISDN (Integrated Services Digital
Network)• A system of digital phone connections allowing a single wire or optical fiber to carry voice, digital network services, and video. Intended to replace POTS (plain old telephone system)
3.2 Alternative Connections
• Cable modem •Most widely subscribed
•Typically faster than DSL
•Typically an external device
3.2 Alternative Connections
• DSL (Digital Subscriber Line) *leading method
• Plugs into the existing LAN
• Best available method of connection
• Wireless
• No physical connection
• Mobility and adaptability
3.2 Alternative Connections
• Bandwidth- the amount of data that can be sent through a given communications circuit per second.
Wireless Terms
• WAP (Wireless Applications Protocol)- allowing device manufactures and service providers to be bale to talk to each other, so that digital content can be delivered to consumers through the air regardless of standard used.
• WML (Wireless Markup Language)- language used to specify content and user interface.
Wireless Terms
• W-CDMA or I-Mode- allows one to view 256 color graphics and HTML on their phones.
• HDML (Handheld Device Markup Language)- uses its own gateway to provide access to the wireless Web.
• XML (External Markup Language)- markup symbols to describe the content of a page or file.
3.3 Networking: LAN and WAN
• LAN- local area network• A high speed data communication network
that connects computers and other terminals within a geographically limited area, typically within adjacent buildings or complexes.
• It is different from PANs (personal area networks) MANs (metropolitan area networks), or WANs (wide area networks).
• LANs are typically faster than WANs
3.3 Networking: LAN and WAN
• Benefits of using networks• Allows sharing of resources like
printers
• Easy and fast information sharing
• Share software
• Response to service request is faster and better
3.3 Networking: LAN and WAN
• Early LANs were vendor specific and used different standards.
• Today there are two common wiring technologies for a LAN, Ethernet and Token Ring.
3.3 Networking: LAN and WAN
• Wireless technologies are starting to evolve and are convenient for Mobile computer users.
• When using Ethernet the computers are usually wired to a hub or to a switch. This constitutes the physical transport mechanism.
3.3 Networking: LAN and WAN
• LANs can be interlinked by connections to form a Wide area network. A router is used to make the connection between LANs.
3.3 Networking: LAN and WAN
• WAN- wide area network
• Typically the same as a LAN but covers more geographical area.
LAN Terms• Firewall- is a set of related software programs
that protect the resources of a LAN or a private network from users from other networks.
• Four main LAN systems:
• Ethernet
• Token Ring
• Arcnet System
• FDDI
Figure 3.3
LAN Internet
Computer
Computer
ComputerComputer
Computer
FirewallComputer
Internet
Location of a firewall, which guards against unauthorized access to a LAN or Internet.