MIS chapter 7
the domain name system
(converts IP addresses to domain names Hierarchical structure Top-level domains) -is a hierarchical system with a root domain, top-level domains, second-level domains, and host computers at the third level.
internet2
-Advanced networking consortium Universities, businesses, government agencies, other institutions -Developed high-capacity 100 Gbps testing network -Testing leading-edge new technologies for Internet
transmission speed
-Bps, Mbps: rate of information transmitted -Hertz: Number of cycles per second -Bandwidth: Difference between highest and lowest frequencies on single channel
types of networks
-Campus-area networks (CANs) -Wide-area networks (WANs) -Metropolitan-area networks (MANs) -Local area networks (LANS)
Client/server computing
-Distributed computing model -Clients linked through network controlled by network server computer -Server sets rules of communication for network and provides every client with an address so others can find it on the network -Has largely replaced centralized mainframe computing
networks in large companies... components include:
-Hundreds of local area networks (LANs) linked to firmwide corporate network -Various powerful servers Web site Corporate intranet, extranet Backend systems -Mobile wireless LANs (Wi-Fi networks) -Videoconferencing system -Telephone network -Wireless cell phones
Packet switching
-Method of slicing digital messages into parcels (packets), sending packets along different communication paths as they become available, and then reassembling packets at destination -Previous circuit-switched networks required assembly of complete point-to-point circuit -Packet switching more efficient use of network's communications capacity
Wireless sensor networks (WSNs)
-Networks of hundreds or thousands of interconnected wireless devices embedded into physical environment to provide measurements of many points over large spaces -Used to monitor building security, detect hazardous substances in air, monitor environmental changes, traffic, or military activity -Devices have built-in processing, storage, and radio frequency sensors and antennas -Require low-power, long-lasting batteries and ability to endure in the field without maintenance -Major sources of "Big Data" and fueling "Internet of Things"
convergence
-Telephone networks and computer networks converging into single digital network using Internet standards -Cable companies providing voice service
the internet
-worlds most extensive network -internet service providers (ISPs) provide connections
access points
: device with radio receiver/transmitter for connecting wireless devices to a wired LAN -uses radio waves to transmit network signals from the wired network to the client adapters, which convert them into data that the mobile device can understand. The client adapter then transmits the data from the mobile device back to the access point, which forward the data to the wired network
semantic web
A collaborative effort led by W3C to add layer of meaning to the existing Web
Uniform resource locators (URLs)
Addresses of Web pages E.g., http://www.megacorp.com/content/features/082602.html
Department of Defense reference model for TCP/IP (4 layers)
Application layer Transport layer Internet layer Network interface layer
competing standards for cellular service
CMA: united states only GSM: rest of world, AT&T, Tmobile
Major components in simple network
Client computer Server computer Network interfaces Connection medium Network operating system (NOS) Hub or switch -routers -software defined networking(SDN)
Transmission Control Protocol/Internet Protocol (TCP/IP)
Common worldwide standard that is basis for Internet
Hypertext Transfer Protocol (HTTP):
Communications standard used for transferring Web pages
TCP/IP and connectivity
Connectivity between computers enabled by protocols
Packet-Switched Networks and Packet Communications
Data are grouped into small packets, which are transmitted independently over various communications channels and reassembled at their final destination. ex: email sending a photo
bandwidth
Difference between highest and lowest frequencies on single channel
Internet services
E-mail Chatting and instant messaging Newsgroups Telnet File Transfer Protocol (FTP) World Wide Web
search engines
Early1990s engines used keyword indexes Google implemented page ranking
4th gen networks
Entirely packet-switched Up to 100 Mbps
LANS( local area networks)
Ethernet is standard for physical medium Workgroup network model (peer-to-peer architecture) Windows domain network model
semantic search
Goal is to include understanding of human language and behavior to deliver more relevant results
3rd gen networks
Higher transmission speeds suitable for web browsing but not Web browsing
Professional organizations and government bodies establish Internet standards
IAB ICANN W3C
bluetooth
Links up to 8 devices in 10-m area using low-power, radio-based communication Useful for personal networking (PANs) - enables a variety of devices, including cell phones, PDAs, wireless keyboards and mice, PCs, and printers, to interact wirelessly with each other within a small 30-foot (10-meter) area. In addition to the links shown, Bluetooth can be used to network similar devices to send data from one PC to another, for example.
broad band
More than 75 percent U.S. Internet users have broadband access
The Future Internet: IPv6 and Internet 2 IPv6
New addressing scheme for IP numbers Will provide more than a quadrillion new addresses Not compatible with current IPv5 addressing
Internet architecture and governance
No formal management: IAB, ICANN, W3C The future Internet: IPv6 and Internet2
Hertz:
Number of cycles per second
Network service providers
Own trunk lines (high-speed backbone networks)
Regional telephone and cable TV companies
Provide regional and local access
wi-fi
Set of standards: 802.11a, 802.11b, 802.11g, 802.11n Used for wireless LAN and wireless Internet access Use access points: device with radio receiver/transmitter for connecting wireless devices to a wired LAN
web servers
Software for locating and managing Web pages
internet network architecture
The Internet backbone connects to regional networks, which in turn provide access to Internet service providers, large firms, and government institutions. Network access points (NAPs) and metropolitan area exchanges (MAEs) are hubs where the backbone intersects regional and local networks and where backbone owners connect with one another.
corporate network infrastructure
Today's corporate network infrastructure is a collection of many different networks from the public switched telephone network, to the Internet, to corporate local area networks linking workgroups, departments, or office floors.
Radio frequency identification (RFID
Use tiny tags with embedded microchips containing data about an item and location Tag antennas to transmit radio signals over short distances to special RFID readers, which send data over network to computer for processing -common uses: automated toll-collection, tracking goods in a supply chain
broadband wireless
Voice and data communication as well as Internet access are increasingly taking place over broadband wireless platforms
wimax(802.16
Wireless access range of 31 miles Require WiMax antennas
blogs
chronological, informal Web sites created by individuals
wikis
collaborative web sites where visitors can add, delta, or modify content on the site
VOIP phone call
digitizes and breaks up a voice message into data packets that may travel along different routes before being reassembled at the final destination. A processor nearest the call's destination, called a gateway, arranges the packets in the proper order and directs them to the telephone number of the receiver or the IP address of the receiving computer.
social search
effort to provide more relevant results by including pages visited by users social network
social networking sites
enables users to build communities of friends and share information
visual search
facial recognition software
HTML (Hypertext Markup Language):
formats documents for display on web
most popular search engine
predictive search
guesses what you're looking for
intelligent agent shopping bots
intelligent agent software for searching internet for shopping information ex: pricegrabber
VPN
is a private network of computers linked using a secure "tunnel" connection over the Internet. It protects data transmitted over the public Internet by encoding the data and "wrapping" them within the Internet Protocol (IP). By adding a wrapper around a network message to hide its content, organizations can create a private connection that travels through the public Internet.
the internet
largest implementation of client/server computing
search engine marketing
major source of internet advertising revenue
mobile search
now 50% of all searches in 2015
hotspots
one or more access points in public place to provide maximum wireless coverage for a specific area
SEO
process of improving rankings in search engine results with search engine optimization -Google updates algorithm to mitigate link farming
Bps, Mbps:
rate of information transmitted
protocols
rules that govern transmission of information between two points
RSS ( really simple syndication)
syndicates web content so aggregator software can pull content for use in another setting or viewing later
modem
translates digital signals into analog form. translates 1's and 0's.
transmission media
types: : twisted pair wire, coaxial cable, wireless speeds: Wide range depending on software/hardware combination
