Paper+3+2010+-+Key+Terms

toc =Backup software=

Backup software is much like insurance carried out by a robot. A computer program makes exact copies of the f ile, data, database, system or server from an original source such as a hard drive and stores it on a backup drive, so that when a disaster, or file corruption occurs, work can be recovered. user:ChingFung

In case of a hard drive crash, back up of data should be carried out regularly to prevent loss of data. Macs have an application called Time Machine, which allows the user to back up data and set up a profile what will allow the user to save it on a machine or export it to a hard drive. A schedule can be set automatically for the computer to perform backups. Options of External hard drive backup options:


 * Extrernal Hard drive
 * Cloud storage (backing up data online but not always secure)
 * CDs
 * DVDs
 * Flashdrive 1272272717

Backup software has a few signature types: -Volumes: the ability to compress and split backup data into separate parts for storage on smaller, removable media (e.g. CD) -Remote: automatically back up data to offsite data centers (sometimes called vaults) via the Internet -Transaction: To prevent loss of previously backed up data during a backup, some backup software offer Transaction mechanism for all critical processes (such as backups or merges) to guarantee the backups' integrity. user:ZetaZero
 * Compression is a common technique to save storage space when backing up. This is why most backups cannot be immediately put back into use.

=Broadband Wireless Access=

Wireless communication technique with higher data rate transmission over greater distances and more rapid deployment than cable. 1269980070

Broadband means 'having instantaneous bandwidth greater than around 1 MHZ and supporting data rates greater than about 1.5 Megabits/s. This means that //Wireless Broadband// features speeds roughly equivalent to wired broadband access, such as that of ADSL or a cable modem. 1272508480

=Client/server network= 1269980545

A client server network is defined as specific type of online network comprised of a single central computer acting as a server that directs multiple other computers, which are referred to as the clients. By accessing the server, clients are then able to reach shared files and information saved on the serving computer. Further, client server networks are very similar in nature to peer to peer networks with the exception that it is only the server that can initiate a particular transaction. 1270715523

 The term // client-server // refers to a popular model for computer networking that utilizes client and server devices each designed for specific purposes. The client-server model can be used on the Internet as well as [|local area networks (LANs)]. Examples of client-server systems on the Internet include __Web browsers and Web servers__, [|FTP] clients and servers, and [|DNS].

A **server devic**e typically stores files and databases including more complex applications like Web sites. Server devices often feature higher-powered central processors, more memory, and larger disk drives than clients.
 * Client devices** are typically PCs with network software applications installed that request and receive information over the network. Mobile devices as well as desktop computers can both function as clients.

Many home networks utilize client-server systems without even realizing it. [|Broadband routers], for example, contain [|DHCP] servers that provide IP addresses to the home computers (DHCP clients). Other types of network servers found in home include // print servers // and // backup servers //.

__Advantages__ · The client-server model was originally developed to allow more users to share access to database applications.
 * Compared to the mainframe approach, client-server offers improved scalability because connections can be made as needed rather than being fixed.
 * The client-server model also supports modular applications that can make the job of creating software easier
 * Client-server is just one approach to managing network application
 *  Keeps data secure


 * The primary alternative, // peer-to-peer // networking, models all devices as having equivalent capability rather than specialized client or server roles. Compared to client-server, peer to peer networks offer some advantages such as more flexibility in growing the system to handle large number of clients. Client-server networks generally offer advantages in keeping data secure. 1272957538

=CT scanner= 1269980545 CT (computerised tomography) scanner: a special kind of X-ray machine. Instead of sending out a single X-ray through your body as with ordinary X-rays, several beams are sent simultaneously from different angles. A computer can use the information from the CT scanner to work out the relative density of the tissues examined 1270715523

There are several advantages that CT has over traditional 2D radiography. First, CT completely eliminates the superimposition of images of structures outside the area of interest. Second, because of the inherent high-contrast resolution of CT, differences between tissues that differ in physical density by less than 1% can be distinguished. Finally, data from a single CT imaging procedure consisting of either multiple contiguous or one helical scan can be viewed as images in the axial, coronal, or sagittal planes, depending on the diagnostic task. This is referred to as multiplanar reformatted imaging. user:ZetaZero

=Data redundancy=

Very simply, the storing of data multiple times. In data tables, data redundancy can cause unnecessary increases in database size, as well as cause database searches to come up with multiple duplicates. A solution is to use data normalization to prevent redundancy. 1269981942

=Disaster recovery=

Disaster recovery is the process, policies and procedures related to preparing for recovery or continuation of technology infrastructure critical to an organization after a natural or human-induced disaster. 1269981942

Disaster can be classified in two broad categories. Viz, 1) Natural disasters—Preventing a natural disaster is very difficult, but it is possible to take precautions to avoid losses. These disasters include flood, fire, earthquake, hurricane, etc 2) Man made disasters—These disasters are major reasons for failure. Human error and intervention may be intentional or unintentional which can cause massive failures such as loss of communication and utility. These disasters include accidents, walkouts, sabotage, burglary, virus, intrusion, etc. 1272509303

=Embedded IT systems=

A combination of computer hardware and software, and perhaps additional mechanical or other parts, designed to perform a dedicated function. Usually part of a larger, more complete device, embedded systems have real-time constraints so that the processor is not re-programmable by the user.1269981942

Examples of embedded solutions could be portable devices such as digital watches and MP# players, to large stationary installations like traffic light and factory controllers. 1270715523

=EMR=

Electronic medical records, a technologically advanced way to integrate patient medical information with various types of file formats combined into one readable platform. Has been proven both efficient and risky to patient privacy and anonymity. 1269980070

The fact that EMRs can be continuously updated is an advantage, as well as the ability to exchange records between different EMR systems easily. This would facilitate the co-ordination of health care delivery in non-affiliated health care facilities. 1270715523

How does an EMR work??? [] 1272272766

Even though EMR systems with computerized provider order entry (CPOE) have existed for more than 30 years, fewer than 10 percent of hospitals as of 2006 have a fully integrated system. In the United States, 38.4% of office-based physicians reported using fully or partially electronic medical record systems (EMR) in 2008. However, the same study found that only 20.4% of all physicians reported using a system described as minimally functional and including the following features: orders for prescriptions, orders for tests, viewing laboratory or imaging results, and clinical notes. 1272509808

=Failover systems=  A system, redundant or standby computer server, system, or network, switched over automatically upon the situation of a disaster, physical disruption, ensuring uninterrupted data flow and operability. 1269981942

At server-level, failover automation takes place using a "Heartbeat" cable that connects two servers. As long as a regular "pulse" or "heartbeat" continues the main server to the second server, the second server will not initiate its systems. There may also be a third "spare parts" server that has running spare components for "hot" switching to prevent down time. A good article about how to test Failover systems: [] 1272509303

=File server=

A computer that provides and data files to all connected users in a local network. It generally works as a request-and-send operation. The central repository of shared computer files in a computer network. 1269980070 1272512470

=Firewall=

A security system for a computer consisted of a combination of hardware and software components which block the sensitive information within a computer from intrusions, attacks from crackers generally hailing from the internet, and deliberately allows authorized access through smart technologies. 1269980070

A firewall's basic task is to regulate some of the flow of traffic between computer networks of different trust levels. Typical examples are the Internet which is a zone with no trust and an internal network which is a zone of higher trust. 1272509303

=Internet=

The Internet is a global system of interconnected computer networks that use the standard Internet Protocol Suite (TCP/IP) to serve billions of data transmissions between computers and computer servers. 1269980070

=Intranet=

An internal private computer network usually used within an office or company. It may or may not be connected to the wider Internet. North Korea, for example, is an extremely large Intranet because it does not "go global". 1269980070

=LAN hardware and software=

LAN hardware 1269981942

=Network server=

1269981942

Network server: a computer that provides various shared resources, such as disk space, hardware access and email services etc, to workstations and other servers on a computer network. 1270715523

=Peer-to-peer network=

A computer network that relies primarily on the computing power and bandwidth of the participants in the network rather than concentrating it in a relatively low number of servers. Notable software examples which use P2P are LimeWire and BitTorrent.1269980070

In P2P networks, clients provide resources, which may include bandwidth, storage space, and computing power. As nodes arrive and demand on the system increases, the total capacity of the system also increases. In contrast, in a typical client–server architecture, clients share only their demands with the system, but not their resources. In this case, as more clients join the system, less resources are available to serve each client. user:ZetaZero

=Security software and hardware= Norton Security 1269981942

Types of Security software: -Antivirus -Cryptographic (aka Encryption software) -Firewall -Spyware/Adware remover user:ZetaZero

=Server= A computer, or a software package, that provides a specific kind of service to client software running on other computers. The term can refer to a particular piece of software, such as a WWW server, or to the machine on which the software is running.1269981942

=VPN=

Virtual private network -- utilizing a public network, with an addition of software, to transmit private data. It is meant to provide security using encrypted tunnels or services which link data transmission through a remote computer. 1269980070

A very good example (with Analogy) of how VPNs work and why they exist. [] user:ZetaZero

=WiFi=

Wireless LAN that uses high frequency radio signals to transmit and receive data over distances of a few hundred feet without the need of cable. Ethernet protocol is used. 1269980070

The term //Wi-Fi// suggests //Wireless Fidelity//, resembling the long-established audio-equipment classification term //high fidelity// (in use since the 1930s). Even the Wi-Fi Alliance itself has often used the phrase //Wireless Fidelity// in its press releases and documents. 1272509808