November-2010
Computer Virus
A computer
virus is a computer
program or piece of code that can replicate itself and spread from
one computer to another. A computer virus is loaded onto computer without user’s
knowledge and runs against his/her wishes. All computer viruses are man-made. A simple virus
that can make a copy of itself
over and over again is relatively easy to produce. Even such a simple virus is
dangerous because it will quickly use all available memory and bring the system to a halt. An even more dangerous type of
virus is one capable of transmitting itself across networks and bypassing security systems.
Types of Viruses
There are many types of computer viruses:
- File virus: Most viruses fall into this category. A virus attaches itself to a file, usually a program file.
- Boot sector virus: These viruses infect floppy and hard drives. The virus program will load first, before the operating system.
- Macro Virus: This is a new type of virus that use an application's own macro programming feature to distribute themselves. Unlike other viruses, macro viruses do not infect programs; they infect documents.
- Virus Hoax: Although there are thousands of viruses discovered each year, there are still some that only exist in the imaginations of the public and the press - known as virus hoaxes.
Disadvantages of computer
virus
In the modern world our lives revolve
around the computer and the internet. Without these it is simply not possible
to envision a single day. We are totally dependent on the technology to get on
with our regular activities. In such a scenario anything which threatens the
data present in the computer is extremely debilitating indeed. Viruses can
really make the life of computer users a living hell. Once they enter the
system there is simply nothing to do but to rue the absence of a sturdy
firewall. Virus remover
programs are really the savior of all those whose lives are totally machine
dependent.
Antivirus software has to be installed in
the machine if you really give priority to the safety of the data stored there.
A computer virus weakens the system, makes it prone to outside attacks of each
and every kind. Not only that the machine slows down quite perceptibly and this
increase with the length of time, the virus is allowed to remain inside. Virus
and malware removal
should become the utmost priority once you find that there is an uninvited
guest present in your machine. Formatting followed by the addition of good
antivirus software are some of the basic steps which need to be taken.
Phishing
Phishing is the act of
attempting to acquire information such as usernames, passwords, and
credit card details (and sometimes, indirectly, money) by masquerading as a
trustworthy entity in an electronic
communication. Phishing is a type of online identity theft. It uses
email and fraudulent websites that are designed to steal one’s personal data or
information such as credit card numbers, passwords, account data, or other
information.
Phishing messages usually take the form of
fake notifications from banks, providers, e-pay systems and other
organizations. The notification will try to encourage a recipient, for one
reason or another, to urgently enter/update their personal data. Such excuses
usually relate to loss of data, system breakdown, etc.
Digital
signature
A digital
signature (standard electronic signature) takes the concept of
traditional paper-based signing and turns it into an electronic
"fingerprint.” This "fingerprint,” or coded message, is unique to
both the document and the signer and binds both of them together. A
digital signature ensures the authenticity of the signer. Any changes made to
the document after it has been signed invalidate the signature, thereby
protecting against signature forgery and information tampering. As such,
digital signatures help organizations sustain signer authenticity,
accountability, data integrity and the non-repudiation of signed electronic
documents and forms.
Digital signature software is a powerful
business tool that provides your customers, employees, vendors, and other
partners the ability to fill out and sign documents online. Contracts,
non-disclosure agreements, employment applications, forms, and dozens of other
business documents can be executed in a web browser. This technology is secure,
legally robust, and efficient, and saves all parties time, money, and hassle.
Many people use the terms “e-signature” and
“digital signature” interchangeably. However, an electronic signature and a
digital signature are two different types of consent, from both a legal and a
technological perspective.
If a signature is digital, electronic, or
written by hand on paper the old-fashioned way, the intent is the same. All
three forms of signature indicate that the party signing a document agrees to
the terms therein.
What Is a Website?
A website is a collection of web pages served
from a single web
domain. A web page is what you see on the screen when you type in a
web address, click on a link, or put a query in a search engine. A web page can
contain any type of information, and can include text, color, graphics,
animation and sound. A website is hosted on at least one web server,
accessible via a network such as the Internet or a
private local
area network through an Internet address known as
When someone gives you their web address,
it generally takes you to their website's home page, which should introduce you
to what that site offers in terms of information or other services. From the
home page, you can click on links to reach other sections of the site. A
website can consist of one page, or of tens of thousands of pages, depending on
what the site owner is trying to accomplish.
Cache
Memory
Cache
memory is extremely fast memory that is built into a computer’s central
processing unit (CPU),
or located next to it on a separate chip. The CPU uses cache memory to store
instructions that are repeatedly required to run programs, improving overall
system speed. The advantage of cache memory is that the CPU does not have to
use the motherboard’s
system bus for data transfer. Whenever data must be passed through the system
bus, the data transfer speed slows to the motherboard’s capability. The CPU can
process data much faster by avoiding the bottleneck created by the system bus.
As
it happens, once most programs are open and running, they use very few
resources. When these resources are kept in cache, programs can operate more
quickly and efficiently. All else being equal, cache is so effective in system
performance that a computer running a fast CPU with little cache can have lower
benchmarks than a system running a somewhat slower CPU with more cache. Cache
built into the CPU itself is referred to as Level 1 (L1) cache. Cache
that resides on a separate chip next to the CPU is called Level
2 (L2) cache. Some CPUs have both L1 and L2 cache built-in and
designate the separate cache chip as Level 3 (L3) cache.
B.
SWIFT
The Society
for Worldwide Interbank Financial Telecommunication (SWIFT) provides a
network that enables financial institutions worldwide to send and receive
information about financial transactions in a secure, standardized and reliable
environment. SWIFT also markets software
and services to financial institutions, much of it for use on the SWIFTNet
Network, and ISO 9362 bank
identifier codes (BICs) are popularly known as "SWIFT codes".
SWIFT does not facilitate funds transfer;
rather, it sends payment orders, which must be settled by correspondent
accounts that the institutions have with each other. Each financial
institution, to exchange banking transactions, must have a banking relationship
by either being a bank or affiliating itself with one (or more) so as to enjoy
those particular business features.
Founded in Brussels in 1973, the Society for the
Worldwide Interbank Financial Telecommunication (SWIFT) is a co-operative
organization dedicated to the promotion and development of standardized global
interactivity for financial transactions. SWIFT's original mandate was to
establish a global communications link for data processing and a common
language for international financial transactions. The Society operates a messaging
service for financial messages, such as letters of credit, payments, and
securities transactions, between member banks worldwide. SWIFT's essential
function is to deliver these messages quickly and securely -- both of which are
prime considerations for financial matters. Member organizations create
formatted messages that are then forwarded to SWIFT for delivery to the
recipient member organization. SWIFT operates out of its Brussels
headquarters and processes data at centers in Belgium
and the United States.
Who Uses SWIFT?
Although originally
the network was designed to support the requirements of Treasury and
Correspondent banking operations, it has over the years allowed other
institutions access to the services, albeit in some cases only to a limited
degree. Currently the following types of organizations can access the service:
- Banks
- Trading Institutions
- Money Brokers
- Securities Broker Dealers
- Investment Management Institutions
- Clearing Systems and Central Depositories
- Recognised Exchanges
- Trust and Fiduciary Service Companies
- Subsidiary Providers of Custody and Nominees
- Treasury Counterparties
- Treasury ETC Service Providers
- Corporates
SWIFT operates a
number of services, primarily;
1.
General
Purpose Application, which only allows system messages, i.e. messages from a
user to SWIFT and vice versa, not from one user to another.
2.
Financial
Application, which is the user to user service comprising System Messages
MT0nn, User-to-User Messages MT1nn through 9nn and Service Messages such as
Acknowledgements.
Additionally, SWIFT
provides a number of services that are charged for over and above the normal
fees. A few of these are:
- IFT (Interbank File Transfer) -For bulk file transfer of messages, for example low net value, high volume retail payments.
- ACCORD - A centralised confirmation matching bureau service.
- Directory Services - An automated and centralised Standard Settlement Instruction service for message enrichment that at present is limited to Treasury and Payment information.
- RTGS (Y-copy) - Mostly used for sending a copy of a message or parts thereof to a third party, for example a Central Bank
- Country Specific (e.g. CREST, CHAPSEuro) - Where SWIFT are either the carrier of the messages or the supplier of additional network services.
Bangladesh Automated Clearing House (BACH)
BACH, the first
ever electronic clearing house of Bangladesh, has two components -
- The Automated Cheque Processing System and
- The Electronic Funds Transfer.
Both the systems operate in batch
processing mode – transactions received from the banks during the day are
processed at a pre-fixed time and settled through a single multilateral netting
figure on each individual bank’s respective books maintained with the
Bangladesh Bank. A state-of-the-art Data Center (DC) and a Disaster Recovery
Site (DRS) have been established comprising of most modern software and
hardware for dealing with the operations of BACH. A Virtual Private Network
(VPN) has been created between the participating commercial banks and Data Center
(DC) & Disaster Recovery Site (DRS) for communicating necessary information
related to BACH. Digital Certificate has been formulated for the first time in Bangladesh for
secured data communication.
The automated clearinghouse (ACH) system is
a nationwide network through which depository institutions send each other
batches of electronic credit and debit transfers. The direct deposit of
payroll, social security benefits, and tax refunds are typical examples of ACH
credit transfers. The direct debiting of mortgages and utility bills are typical
examples of ACH debit transfers. While the ACH network was originally used to
process mostly recurring payments, the network is today being used extensively
to process one-time debit transfers, such as converted check payments and
payments made over the telephone and Internet.
The Reserve Banks and Electronic Payments
Network (EPN) are the two national ACH operators. As an ACH operator, the
Reserve Banks receive files of ACH payments from originating depository
financial institutions, edit and sort the payments, deliver the payments to
receiving depository financial institutions, and settle the payments by
crediting and debiting the depository financial institutions' settlement
accounts. The Reserve Banks and EPN rely on each other to process interoperator
ACH payments--that is, payments in which the originating depository financial
institution and the receiving depository financial institution are served by
different operators. These interoperator payments are settled by the Reserve
Banks.
Basics of ACH Payments
ACH payments are
simply electronic transfers from one account to another. Common uses of ACH
payments are:
- Customer pays service provider
- Employer deposits money to employee account
- Consumer moves funds from one bank to another
- Business pays supplier for products
Because they’re electronic, ACH payments
use fewer resources (paper, ink, fuel to transport checks, etc). In addition,
ACH payments make it easier to keep track of finances. Instead of generic check
information on a bank statement, you see the other party’s name if you’ve used
an ACH payment. Then it’s easier to categorize the transaction with your
financial software. ACH payments can be
electronic from start-to-finish, or they can happen when a paper check is
converted and processed electronically.
What
is a Cheque Truncation System?
Cheque
Truncation System (CTS) is a cheque clearing system for faster clearing of
cheques. As the name suggests, truncation is the process of stopping the flow
of the physical cheque in its way of clearing. In its place an electronic image
of the cheque is transmitted with key important data.
Cheque
truncation thus obviates the need to move physical instruments across branches.
This effectively eliminates the associated cost of movement of physical cheques,
reduces the time required for their collection and brings elegance to the
entire activity of cheque processing. It is a system which is practiced
worldwide in the banking sector.
Truncation means, stopping the flow of the physical cheques issued by a
drawer to the drawee branch. The physical instrument is truncated at some point
en route to the drawee branch and an electronic image of the cheque is sent to
the drawee branch along with the relevant information like the MICR fields, date of
presentation, presenting banks etc.
Cheque truncation, would eliminate the need to
move the physical instruments across branches, except in exceptional
circumstances. This would result in effective reduction in the time required
for payment of cheques, the associated cost of transit and delays in
processing, etc., thus speeding up the process of collection or realization of
cheques.
What are the
benefits of CTS to bank customers?
- The main feature of the CTS 2010 cheque is that the physical movement of the cheque is stopped and the images of cheques are transmitted electronically thereby speeding up the process of cheque clearance and settlement between banks. This obviously means quicker clearance, shorter clearing cycle and speedier credit of the amount to your account.
- With the movement of cheques from one bank to another having been stopped, there is no fear of loss of cheques in transit and chances of cheques being lost due to mishandling, etc are totally avoided.
- At present clearing is restricted to banks operating within a city or within a restricted geographical area. Under the CTS, it is proposed to integrate multiple clearing locations managed by different banks in different centres so that cheques drawn on upcountry banks too can be cleared electronically without any geographical restrictions. Eventually, this will result in integration of clearing houses into a nation-wide standard clearing system, thereby making clearance of cheques drawn on any bank in India within 24 hours possible.
- The cheques in transit are most susceptible to frauds and customers of banks are the worst sufferers in the present system of physical movement of cheques from one place to another. Under the CTS system moving of physical cheques at different points is obviated as only electronic images are transmitted between banks, and this will considerably reduce the scope for perpetuation of frauds inherent in paper instruments.
- With the introduction of homogeneity in security features under CTS standards 2010 such as embedded verifiable features like bar codes, encrypted codes, logos, watermarks, holograms, etc in every cheque leaf, it is now possible to detect frauds easily through interception of altered and forged instruments while passing through the electronic imaging system. This is expected to considerably reduce operational risks and risks associated with paper clearing for the benefit of all bank customers.
- The CTS is expected to improve operational efficiency of the entire banking system, resulting in better customer service, improved liquidity position for banks’ customers and safe and secure banking for the entire banking public.
What are MICR, OMR and OCR?
MICR:
MICR stands for Magnetic-Ink Character Recognition.
It is a special scanner. It reads the characters printed with magnetic ink and
converts them into digital signals. These signals are then input to the
computer for further processing. MICR devices are normally used in banks for
processing cheques. MICR is used
extensively in banking because magnetic-ink characters are difficult to forge
and are therefore ideal for marking and identifying cheques.
OMR:
OMR stands for
Optical Marks Recognition. OMR device is used to read handwritten marks or
symbols printed on the paper. It uses a light beam to scan the marks and
converts them into digital signals. These signals are then input to the
computer for further -processing. OMR device is usually used in education field
to check (or mark) the objective type answers of the questions.
OCR:
OCR stands for
Optical Character Recognition. OCR device reads preprinted characters in a
particular font and converts them into digital code. The characters printed on
paper may be typewritten or handwritten. The OCR devices are commonly used to
process utility bills and price code printed on the products in departmental
stores.
Business continuity planning (BCP)
Business
continuity planning
(BCP) is a set of documents, instructions, and
procedures which
enable a business to
respond to accidents, disasters, emergencies,
and/or threats without
any stoppage or hindrance in its key operations. It is
also called business continuity and resiliency planning (BCRP). A
business continuity plan is a roadmap for continuing operations under adverse
conditions such as a storm or a crime.
Creating and
maintaining a BCP helps ensure that your business has the resources and
information needed to deal with an emergency. Other benefits include:
- Enhance your business image with employees, shareholders and customers by demonstrating a proactive attitude.
- Improve efficiency in the overall organization.
- Identify the relationship of assets both human and financial resources with respect to critical services and deliveries.
e-Governance
Several dimension and factors influence the
definition of e-Governance. The word “electronic” in the term
e-Governance implies technology driven governance. E-Governance is the
application of Information and Communication Technology (ICT) for delivering
government services, exchange of information communication transactions,
integration of various stand-alone systems and services between
Government-to-Citizens (G2C), Government-to-Business (G2B), Government-to-Government
(G2G) as well as back office processes and interactions within the entire
government frame work. Through the e-Governance, the government services will
be made available to the citizens in a convenient, efficient and transparent
manner. The three main target groups that can be distinguished in governance
concepts are Government, citizens and businesses/interest groups. In
eGovernance there are no distinct boundaries.
e-Government refers to government's use of
information technology to exchange information and services with citizens,
businesses, and other arms of government. e-Government may be applied by the
legislature, judiciary, or administration, in order to improve internal
efficiency, the delivery of public services, or processes of democratic
governance. It also refers to the citizen to government interaction including
the feed back of policiesThe primary delivery models are Government-to-Citizen
or Government-to-Customer (G2C), Government-to-Business (G2B) and
Government-to-Government (G2G) & Government-to-Employees (G2E). The most
important anticipated benefits of e-government include improved efficiency,
convenience, and better accessibility of public services.
Computer network
A
computer network is a telecommunications network that connects
a collection of computers to allow communication and data exchange between
systems, software applications, and users. The computers that
are involved in the network that originate, route and terminate the data are
called nodes.
The interconnection of computers is accomplished with a combination of cable or
wireless media and networking hardware.
Two
devices are said to be networked when a process in one device is able to exchange
information with a process in another device. Networks may be classified by
various characteristics, such as the media used to transmit signals, the communications protocols used to organize
network traffic, network scale, network
topology and organizational scope. The best-known computer network is the Internet.
Communication
protocols define the rules and data formats for exchanging information in a
computer network. Well-known communications protocols include Ethernet, a
hardware and link layer standard that is widely used for local area networks, and the Internet protocol suite (TCP/IP), which
defines a set of protocols for communication between multiple networks, for
host-to-host data transfer, and for application-specific data transmission
formats. Protocols provide the basis for network programming.
Advantages of Computer Network
- Networks allow data transmission among far areas also within local areas.
- Networks allow different users share the processing characteristics of different computers.
- Network allows users to share common set of data files and software stored in a main system.
- Network allows users to share common hardware resources such as printers, fax machines, modem etc.
- The cost of computing is reduced to each user as compared to the development and maintain of each single computer system.
One way to categorize the different types
of computer network designs is by their scope or scale. For historical reasons,
the networking industry refers to nearly every type of design as some kind of area
network. Common examples of area network types are:
- LAN - Local Area Network
- WLAN - Wireless Local Area Network
- WAN - Wide Area Network
- MAN - Metropolitan Area Network
- SAN - Storage Area Network, System Area Network, Server Area Network, or sometimes Small Area Network
- CAN - Campus Area Network, Controller Area Network, or sometimes Cluster Area Network
- PAN - Personal Area Network
- DAN - Desk Area Network
LAN - Local Area Network
A LAN connects
network devices over a relatively short distance. A networked office building,
school, or home usually contains a single LAN, though sometimes one building
will contain a few small LANs (perhaps one per room), and occasionally a LAN
will span a group of nearby buildings. In TCP/IP networking, a LAN is often but not always
implemented as a single IP subnet.
In addition to
operating in a limited space, LANs are also typically owned, controlled, and
managed by a single person or organization. They also tend to use certain
connectivity technologies, primarily Ethernet
and Token
Ring.
WAN - Wide Area Network
As the term implies, a WAN spans a large
physical distance. The Internet is the largest WAN, spanning the Earth.
A WAN is a
geographically-dispersed collection of LANs. A network device called a router
connects LANs to a WAN. In IP networking, the router maintains both a LAN
address and a WAN address.
A WAN differs from
a LAN in several important ways. Most WANs (like the Internet) are not owned by
any one organization but rather exist under collective or distributed ownership
and management. WANs tend to use technology like ATM,
Frame
Relay and X.25 for
connectivity over the longer distances.
LAN, WAN and Home Networking
Residences typically employ one LAN and
connect to the Internet WAN via an Internet Service Provider
(ISP) using a broadband modem.
The ISP provides a WAN IP address to the
modem, and all of the computers on the home network use LAN (so-called private)
IP addresses. All computers on the home LAN can communicate directly with each
other but must go through a central gateway, typically a broadband router,
to reach the ISP.
Other Types of Area Networks
While LAN and WAN are by far the most
popular network types mentioned, you may also commonly see references to these
others:
- Wireless Local Area Network - a LAN based on WiFi wireless network technology
- Metropolitan Area Network - a network spanning a physical area larger than a LAN but smaller than a WAN, such as a city. A MAN is typically owned an operated by a single entity such as a government body or large corporation.
- Campus Area Network - a network spanning multiple LANs but smaller than a MAN, such as on a university or local business campus.
- Storage Area Network - connects servers to data storage devices through a technology like Fibre Channel.
- System Area Network - links high-performance computers with high-speed connections in a cluster configuration. Also known as Cluster Area Network.
Encryption & Decryption
Encryption
is the process of translating plain text data (plaintext)
into something that appears to be random and meaningless (ciphertext).
Decryption is the process of converting cipher-text back to plain text.
To
encrypt more than a small amount of data, symmetric encryption
is used. A symmetric key
is used during both the encryption and decryption processes. To decrypt a
particular piece of ciphertext, the key that was used to encrypt the data must
be used.
The
goal of every encryption algorithm is to make it as difficult as possible to
decrypt the generated ciphertext without using the key. If a really good
encryption algorithm is used, there is no technique significantly better than
methodically trying every possible key. For such an algorithm, the longer the
key, the more difficult it is to decrypt a piece of ciphertext without
possessing the key.
It
is difficult to determine the quality of an encryption algorithm. Algorithms
that look promising sometimes turn out to be very easy to break, given the
proper attack. When selecting an encryption algorithm, it is a good idea to
choose one that has been in use for several years and has successfully resisted
all attacks.
In today’s world
Internet has touched each and every aspect of life changing the way we work,
communicate and live. But the major concern has been about the security and
privacy of the data that is being exchanged via Internet especially when you
are sending the sensitive information through it. Amongst many ways of
securing data, encrypting the sensitive data is the most popular and effective
way to have data security. Encryption is translation of data into a secret code
called a cipher text. Decryption is the process of decoding data that has been
encrypted into a secret format this requires secret code or password.
Computer encryption
uses the science of cryptography. As the human-based code is too easy for a
computer to crack, most of the encryption systems belong to the one of two
categories.
1. Symmetric-key encryption:
In Symmetric-key
encryption technique single key is used to encrypt and decrypt the message.
2. Public-key encryption:
While in public-key
(or asymmetric) encryption technique, uses one key (private key) to encrypt a
message while another key (public key) to decrypt the message. Public-key
encryption uses the combination of a private key and a public key. The private
key is kept secret and is only known to the person who encrypts the message,
while the public key is freely disseminated which helps to verify the message.
To decode an encrypted message, receiver uses the public key of the sender and
his own private key.
Encryption/Decryption
is advisable while carrying out any kind of sensitive transaction, such as a
online purchases or the communication of a company sensitive documents between
different departments in the organization etc. Encryption of the data ensures
its secrecy and/or privacy.
Credit Card vs Debit Card
A debit card
is either linked to a bank account or is a prepaid card. In either case, the
card draws on funds that the consumer (owner of the card) has already deposited
with a financial institution. On the other hand, a credit card is a kind
of loan. When a consumer uses a credit card, the financial institution fronts
to the consumer credit (a loan). Purchases are totaled and billed monthly and
the user pays a few weeks after receiving the monthly bill.
Comparison chart
|
|
Credit
Card
|
Debit
Card
|
|
Where
money comes from?:
|
Borrowing money from a bank or financial
institution. (Spending "other's" money)
|
Funds
taken from the money that you have in your bank account. (Spending your
"own" money)
|
|
Can
be used as:
|
Credit
card only
|
Debit
Card and Credit Card
|
|
Line
of Credit:
|
Carries
Line of Credit
|
No
Line of Credit
|
|
PIN
Number:
|
No
|
PIN
number provided, but not is not always asked to punch in.
|
|
Picture
ID asked for:
|
Yes
|
No
|
|
Interest:
|
Pay
additional interest drawn on the amount borrowed.
|
No
|
|
Credit
History:
|
Responsible
credit card usage and payment can improve one's credit rating. Credit cards
typically report account activity to at least one of the three major credit bureaus on a monthly basis.
|
Does
not affect credit history.
|
|
Legal
Liability laws:
|
Strict.
Consumer liability limit for credit card fraud is $50
if the credit card company is notified within 60 days
in written since the fraudulent charges.
|
Lean.
Consumer liability limit for debit card fraud is $50 if the bank is notified
within two days of noticing the fraudulent charges.
|
|
Risk
involved:
|
Low.
|
High,
as they are attached to a bank account. A person does not need a pin number
to use a debit card and therefore can easily drain a persons bank account,
causing extreme problems.
|
|
Fraud:
|
Only
problem is proving that someone else has used the card.
|
With
a debit card the persons has to figure out how to get their money back and if
any checks bounced they are responsible for those as well
|
|
Limit:
|
Credit
line, which can be increased/decreased from the time of applying.
|
Equals
your account limit.
|
|
Overdraw
Fees:
|
Low.Some
credit card companies allow to overdraw amount over the maximum credit line
with a fees
|
High
"overdraft" fees. Possible to overdraw amount over the account
limit
|
|
Connected
to:
|
Need
not be connected to any bank account.
|
Checking
Account;Savings Account
|
|
Monthly
bills:
|
Yes
|
No
|
|
Offers
Protection:
|
Yes.
Example insurance on a rental car
|
No
|
|
Alternate
payment type:
|
cash
|
cheque
& cash
|
Advantages and
Disadvantages of ATM Machines and Bank/Debit Cards
|
|
Advantages
|
Disadvantages
|
|
Debit
Card
|
|
|
|
ATM or Bank Card
|
|
|
ADVANTAGES & DISADVANTAGES OF AN ATM
Advantages of an ATM:
1. An automated
teller machine increases existing business:
2. An automated
teller machine generates new business:
3. An automated
teller machine provides additional revenue streams :
4. An automated
teller machine reduces risk and lowers costs:
Disadvantages:
1. Not available in
remote places.
2. Cannot avoid
illegal use in case of stolen card.
What are Storage devices?
Storage Devices are
the data storage devices that are used in the computers to store the data. The
computer has many types of data storage devices. Some of them can be classified
as the removable data Storage Devices and the others as the non removable data
Storage Devices.
The memory is of
two types; one is the primary memory and
the other one is the secondary memory.
The primary memory is the volatile memory and the secondary memory is the non volatile memory. The volatile memory is the kind of the memory that is erasable and the non volatile memory is the one where in the contents cannot be erased. Basically when we talk about the data storage devices it is generally assumed to be the secondary memory.
The secondary memory is used to store the data permanently in the computer. The secondary storage devices are usually as follows: hard disk drives – this is the most common type of storage device that is used in almost all the computer systems. The other ones include the floppy disk drives, the CD ROM, and the DVD ROM. The flash memory, the USB data card etc.
Storage device
Alternatively
referred to as storage, storage media, or storage medium,
a storage device is a hardware device
capable of holding information. There are two storage devices used in
computers; a primary
storage device such as computer RAM and a secondary storage
device such as a computer hard drive. The
secondary storage could be a removable, internal, or external storage.
In the picture to the right, is an example of a Drobo, an external secondary
storage device. Without a storage device, you and your computer would not be
able to save any settings or information and would be considered a dumb terminal.
Below, are some additional examples of storage devices that are used with computers:
- Floppy diskette
- CD-ROM disc
- CD-R and CD-RW disc
- Cloud storage
- DVD-R, DVD+R, DVD-RW, and DVD+RW disc
- Jump drive and USB flash drive
- Hard drive
- LS-120
- Tape cassette
- Zip diskette
When saving anything on the
computer, you will be asked for the storage location, which is where you
want to save the information. By default most of the information you save will
be saved to your computer hard drive, however, if you want to move the
information to another computer you would want to save it to a removable
storage device such as a Jump drive.
Parity bit
A parity bit
is a single bit
added to a binary
data transmission used to indicate if whether the 0's and 1's within that data
transmission is an even or odd number. The parity bit is used in parity error
checking to find errors that may occur during data transmission. In the picture
to the right, is an example of a 8-bit binary number with the ninth digit being
the parity bit.
A
parity bit, or check bit, is a bit added to the end of a
string of binary
code that indicates whether the number of bits in the string with the value
one
is even
or odd.
Parity bits are used as the simplest form of error detecting code.
There
are two variants of parity bits: even parity bit and odd parity bit. In case of
even parity, the parity bit is set to 1, if the number of ones in a given set
of bits (not including the parity bit) is odd, making the number of ones in the
entire set of bits (including the parity bit) even. If the number of ones in a
given set of bits is already even, it is set to a 0. When using odd parity, the
parity bit is set to 1 if the number of ones in a given set of bits (not
including the parity bit) is even, keeping the number of ones in the entire set
of bits (including the parity bit) odd. when the number of set bits is odd,
then the odd parity bit is set to 0.
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