Isys 414 Chapter 8

Front 1

virtual private network (VPN)

Back 1

A network that controls access to an extranet by encryption and authentication technology.

Front 2

cookie

Back 2

A yummy treat (just kidding). A text file created by a Web site and stored on a visitor's hard drive. Cookies store information about who the user is and what the user has done on the site.

Front 3

field check

Back 3

An edit check in which the characters in a field are examined to ensure they are of the correct field type (e.g., numeric data in numeric fields).

Front 4

sign check

Back 4

An edit check that verifies that the data in a field have the appropriate arithmetic sign

Front 5

limit check

Back 5

An edit check to ensure that a numerical amount in a record does not exceed some predetermined limit.

Front 6

range check

Back 6

An edit check designed to verify that a data item falls within a certain predetermined range of acceptable values

Front 7

size check

Back 7

An edit check that ensures the input data will fit into the assigned field.

Front 8

completeness test (check)

Back 8

An on-line data entry contorl in which the computer checks if all data requred for particular transaction have been entered by the user.

Front 9

validity check

Back 9

An edit test in which an identification number or transaction code is compared witha table of valid identification numbers or codes maintained in computer memory.

Front 10

reasonableness test

Back 10

An edit check of the logical correctness of relationships among data items. For example, a journal entry that debits inventory and credits wages payable is not reasonable.

Front 11

check digit

Back 11

A digit in a data field that provides info about the other digits in the data field. It is used to check for errors or loss of charcters in the data fields as a result of data transfer operations. If data are lost or erroneously changed, the fact that the check digit does not match the other data in the field will sgnal that an error has occured.

Front 12

check digit verification

Back 12

The edit check in which a check digit is recalculated to verfiy that an error has not been made. This calculation can be made only on a data item that has a check digit

Front 13

sequence check

Back 13

An edit check that determines if a batch of input data is in the proper numerical or alphabetical sequence.

Front 14

error log

Back 14

The record of data input and data processing errors.

Front 15

batch totals

Back 15

Sums of the instances of numerical items, calculated for a batch of documents. These totals are calculated prior to processing the batch adn are compared with machine-generated totals at each subsequent processing step to verify that the data was processed correctly.

Front 16

financial total

Back 16

The total of a dollar field, such as total sales, in a set of records. It is usually generated manually from source documents prior to input and compared with machine-generated totals at each subsequent processing step. Any descrepancy may indicate a loss of records or errors in data transcription or processing.

Front 17

hash total

Back 17

A total generated from values for a field that would not usualy be totaled, such as customer account numbers. It is usually generated manually from source documents prior to input and compared iwth machine-generated totals at each subsequent processing step. Any descrepancy may indicate a loss of records or erros in data transcription or processing.

Front 18

record count

Back 18

A total of the number of input documents in a process or the number of records processed at a given time.

Front 19

prompting

Back 19

An on-line data entry otrool that uses the computer to contrl the data entry process. The system displays a request to the user for each required item of input data and then waits for an acceptable response before requesting the next required item.

Front 20

preformatting

Back 20

An online data entry control in whch the computer displays a form on the screen and the user fills in the blanks on the form as needed

Front 21

closed-loop verification

Back 21

An input validation method that uses data entered into the system to retrieve and display other related information so the accuracy of the input data can be verified.

Front 22

transaction log

Back 22

A detailed record of every transaction entered in a system.

Front 23

header record

Back 23

Type of internal label that appears at the beginning of each file and contains the file name, expiration date, and other file identification information.

Front 24

trailer record

Back 24

Type of internal label that appears at the end of each file and serves as an indicator that the end of the file has been reached. Contains the batch totals calculated during input.

Front 25

transposition error

Back 25

An error that results when numbers in two adjacent columns are inadvertently exchanged (for example, 64 is written as 46).

Front 26

cross-footing balance test

Back 26

A procedure in which worksheet data are totaled both across and down. Then, the total of the horizontal totals is compared to the total of the vertical totals to ensure that the worksheet balances.

Front 27

zero-balance test

Back 27

An internal check that requires the balance of an account to be zero after all entries to it have been made.

Front 28

concurrent update controls

Back 28

Controls that lock out one user to protect individual records from potential errors that could occur if two users attempted to update the same record simultaneously.

Front 29

parity bit

Back 29

An extra bit added to a byte and magnetized as needed to ensure that there is always an odd (or even) number of magnetized bits. The computer uses the odd (or even) partiy scheme to check the accuracy of each item of data.

Front 30

parity checking

Back 30

As a computer reads or receives a set of characters, it verifies that there are the proper number of magnetized bits in each character received. If not, the corresponding character may contain an error.

Front 31

echo check

Back 31

A hardware control that verifies transmitted data by having the receiving device send the message back to the sending device so that the message received can be compared with the message sent.

Front 32

fault tolerance

Back 32

The capability of a system to continue performing when there is a hardware failure.

Front 33

uninterruptible power system (UPS)

Back 33

An alternative power supply device that protects against the loss of power and fluctuations in the power level by using battery power to enable the system to operate long enough to back up critical data and safely shut down.

Front 34

backup

Back 34

An exact copy of the most current version of a database, file, or software program.

Front 35

restoration

Back 35

The process of installing the backup copy of a database of files for use in data processing.

Front 36

incremental backup

Back 36

Copying only the data items that have chnaged since the last backup. This produces a set of incremental backup files, each containing the results of one day's transactions.

Front 37

differential backup

Back 37

Copying all changes made since the last full backup. Thus, each new differential backup file contains the cumulative effects of all activity since the last full backup.

Front 38

recovery point objective

Back 38

The length of time between thelast backup and the time htat anincident occurred. The RPO represents the period of time for which management is willing to have to reenter, if possible, data about past transactions.

Front 39

real-time mirroring

Back 39

Maintaining two copies of the database at two separate data centers at all times and updating both copies in real-time as each transaction occurs.

Front 40

checkpoint

Back 40

Any one of a serires of points durig a long processing run at which an exact copy of all the data values and status indicators of a program are captured. Should a system failure occur, the system could be backed up to the most recent checkpoint and processing could begin again at the checkpoint rather than at the beginning of the program.

Front 41

archive

Back 41

A copy of a database, master file, or software that is retained indefinitely as an historical record, usually to satisfy legal and regulatory requirements.

Front 42

recovery time objective (RTO)

Back 42

The time by which the organization's information system must be available again following a disaster.

Front 43

cold site

Back 43

A location that provides everything necessary to quickly install computer equipment in the event of a disaster.

Front 44

hot site

Back 44

Completely operational data processing facility configured to meet the user's requirement that can be made available to a disaster-stricken organization on short notice.