Ch. 6 MIS

The Cloud
The elastic leasing of pooled computer resources over the Internet
Elastic
Computing resources leased can be increased or decreased dynamically, programmatically in a short span of time and that organizations pay for just the resources they use.
Pooled
-A group of servers
-Cloud resources are pooled because many different organizations use the same physical hardware; they share that hardware through virtualization.
-Cloud vendors benefit from economies of scale – average cost of production decreases as size of operation increases
-Major cloud vendors operate enormous data centers (server farms)
Negatives of cloud computing
Loss of control
Computer Network
A collection of computers that communicate with one another over transmission lines or wirelessly
LAN
(Local Area Network) – connects computers that reside in a single geographic location on the premises of the company that operates the LAN. Two to several hundred computers
WAN
(Wide Area Network) – connects computers at different geographic locations. Ex: Computers for a college of business located on multiple campuses
Internet
Network of networks
Intranet
A private internet used exclusively within an organization
Protocol
A set of rules and data structures for organizing communication
SOHO
Small office or home office
IEEE 802.3 protocol (Ethernet)
Used for LAN connection. Also called Ethernet – specifies hardware characteristics, such as which wire carries which signals. Also describes how messages are to be packaged and processed for wired transmissions of the LAN.
10/100/1000 Ethernet
Most personal computers support
IEEE 802.11 protocol
Wireless LAN connections use
Bluetooth
Another common wireless protocol. Designed for transmitting data over short distances, replacing cables.
ISP
(Internet service provider)
-What your actually connecting to when you connect to the Internet
– 3 important function
1) Provides you with a legitimate Internet address
2) Serves as gateway to Internet
3) Pays for the Internet
DSL
Digital subscriber line – operates on the same lines as voice telephones, but it operates so it does not interfere with voice telephone service. DSL’s use their own protocols for data transmission.
Cable lines
Provide high-speed data transmission using cable TV lines
Hop
Movement from one network to another
Packet
A message that moves across the Internet
Networks owned by large telecommunication providers known as …
Carriers
Peering agreements
How large carriers exchange traffic freely without charging each other access fees
Net neutrality principle
All data is created equally – carriers should not be able to decide which sites load quickly, which apps are allowed on a network, and which content is acceptable
IP address
Internet address – a number that identifies a particular device
Public IP address
-Identifies a particular device on public Internet
-Assigned by ICANN (internet Corporation for Assigned Names and Numbers)
-U.S. Department of Commerce no longer has oversight over ICANN
Private IP Address
-Identifies a device on a private network, usually a LAN
-Assignment controlled within LAN
Domain Name
A worldwide-unique name that is affiliated with a public IP address
URL
Uniform Resource Locator- address on the Internet
Three-tier architecture
A design of user computers and servers that consist of 3 categories. 1) user tier 2) server tier 3) database tier
User tier
Consists of computer, phones and other mobile devices that have browsers that request & process webpages
Server tier
Consists of computers that run Web servers and process application programs
Database tier
Consists of computers that run a DBMS that processes requests to retrieve and store data
Web page
Document that is coded in, usually html
Web server
Program that runs on a server-tier computer and manage traffic by sending and receiving Web pages to and from clients
Commerce server
An application program that runs on a server-tier computer
TCP
Transmission Control Protocol – Breaks traffic up into packets and sends each one along its way
IP
Internet Protocol – Specifies routing of data communication through networks. Routers – Small, special purpose computers that route packets to their destination
TCP/IP Protocol Architecture
Defines Internet protocols – 5 layers
1) Physical- Hardware specifications
2) Data Link- Flow among switches and access points
3) Internet- Internet routing
4) Transport- Reliable Internet transport
5) Application- Enable communication among programs
Hypertext Transfer Protocol
(http)- protocol used between browsers and web servers
smtp
Simple Mail Transfer Protocol- used for email transmissions
ftp
File Transfer Protocol- used to move files over the Internet
SaaS
Software as a service- provides not only hardware infrastructure, but an operating system and application programs as well. Ex: iCloud
PaaS
Platform as a service- vendors provide hosted computers an operating system and possible a DBMS. Ex: Microsoft Azure
IaaS
Infrastructure as a service- the cloud hosting of a bare server computer or data storage
CDN
Content delivery network: -System of hardware and software stores user data in many different geographical locations and makes data available on demand.
-Provides specialized types of PaaS but usually considered in its own category
-Minimize latency
-Used to store and deliver content seldom changed
Public IP addresses & domain names
-IPv4 (32 bit)- 4 decimal notation
-IPv6- Eight hexadecimal dotted notation
VPN
Virtual public network- uses public Internet to create appearance of a private connection on secure network
Tunnel
Virtual private pathway over a public or shared network from the VPN client to VPN server
A ________ is a set of rules that programs on two communicating devices follow.
Protocol
A private internet that is used exclusively within an organization is called a(n) ________.
Intranet
A(n) ________ is a number that identifies a particular device.
IP address
A(n) ________ uses the Internet to create the appearance of private, secure connections.
VPN
Computers that reside in different geographic locations are connected using a(n) ________.
WAN
The protocols used on the Internet are arranged according to a structure known as the ________ protocol architecture.
TCP/IP
Which of the following features distinguishes a LAN from a WAN?
LAN connects computers in a single location
Which of the following protocols guarantees secure data transmission?
https
Which of the following refers to the three tiers in the three-tier architecture?
user, server & database
________ are programs that run on a server-tier computer and manage traffic by sending and receiving Web pages to and from clients.
web servers