Information security
means protecting information and information systems
from unauthorized access, use, disclosure, disruption,
modification, or destruction. The terms information
security, computer security and information assurance
are frequently used interchangeably. These fields are
interrelated and share the common goals of protecting
the confidentiality, integrity and availability of
information; however, there are some subtle differences
between them. These differences lie primarily in the
approach to the subject, the methodologies used, and the
areas of concentration. Information security is
concerned with the confidentiality, integrity and
availability of data regardless of the form the data may
take: electronic, print, or other forms.
Governments, military, financial institutions,
hospitals, and private businesses amass a great deal of
confidential information about their employees,
customers, products, research, and financial status.
Most of this information is now collected, processed and
stored on electronic computers and transmitted across
networks to other computers. Should confidential
information about a businesses customers or finances or
new product line fall into the hands of a competitor,
such a breach of security could lead to lost business,
law suits or even bankruptcy of the business. Protecting
confidential information is a business requirement, and
in many cases also an ethical and legal requirement. For
the individual, information security has a significant
effect on privacy, which is viewed very differently in
different cultures.
The field of information security has grown and evolved
significantly in recent years. As a career choice there
are many ways of gaining entry into the field. It offers
many areas for specialization including Information
Systems Auditing, Business Continuity Planning and
Digital Forensics Science, to name a few.
Key concepts
For over twenty years information security has held that
confidentiality, integrity and availability (known as
the CIA Triad) are the core principles of information
security.
Confidentiality
Confidentiality is the property of preventing disclosure
of information to unauthorized individuals or systems.
For example, a credit card transaction on the Internet
requires the credit card number to be transmitted from
the buyer to the merchant and from the merchant to a
transaction processing network. The system attempts to
enforce confidentiality by encrypting the card number
during transmission, by limiting the places where it
might appear (in databases, log files, backups, printed
receipts, and so on), and by restricting access to the
places where it is stored. If an unauthorized party
obtains the card number in any way, a breach of
confidentiality has occurred.
Breaches of confidentiality take many forms. Permitting
someone to look over your shoulder at your computer
screen while you have confidential data displayed on it
could be a breach of confidentiality. If a laptop
computer containing sensitive information about a
company's employees is stolen or sold, it could result
in a breach of confidentiality. Giving out confidential
information over the telephone is a breach of
confidentiality if the caller is not authorized to have
the information.
Confidentiality is necessary (but not sufficient) for
maintaining the privacy of the people whose personal
information a system holds.
Integrity
In information security, integrity
means that data cannot be modified without
authorization. (This is not the same thing as
referential integrity in databases.) Integrity is
violated when an employee (accidentally or with
malicious intent) deletes important data files, when a
computer virus infects a computer, when an employee is
able to modify his own salary in a payroll database,
when an unauthorized user vandalizes a web site, when
someone is able to cast a very large number of votes in
an online poll, and so on.
Availability
For any information system to serve
its purpose, the information must be available when it
is needed. This means that the computing systems used to
store and process the information, the security controls
used to protect it, and the communication channels used
to access it must be functioning correctly. High
availability systems aim to remain available at all
times, preventing service disruptions due to power
outages, hardware failures, and system upgrades.
Ensuring availability also involves preventing DoS
attacks (denial-of-service attacks).
In 2002, Donn Parker proposed an
alternative model for the classic CIA triad that he
called the six atomic elements of information. The
elements are confidentiality, possession, integrity,
authenticity, availability, and utility. The merits of
the Parkerian hexad are a subject of debate amongst
security professionals.
Authenticity
In computing, e-Business and information security it is
necessary to ensure that the data, transactions,
communications or documents (electronic or physical) are
genuine (i.e. they have not been forged or fabricated.)
Non-repudiation
In law, non-repudiation implies one's intention to
fulfill their obligations to a contract. It also implies
that one party of a transaction can not deny having
received a transaction nor can the other party deny
having sent a transaction.
Electronic commerce uses technology such as digital
signatures and encryption to establish authenticity and
non-repudiation.
Risk management
Security is everyone’s
responsibility. Security awareness poster. U.S.
Department of Commerce/Office of Security.
A comprehensive treatment of the topic of risk
management is beyond the scope of this article. We will
however, provide a useful definition of risk management,
outline a commonly used process for risk management, and
define some basic terminology.
The CISA Review Manual 2006 provides the following
definition of risk management: "Risk management is
the process of identifying vulnerabilities and threats
to the information resources used by an organization in
achieving business objectives, and deciding what
countermeasures, if any, to take in reducing risk to an
acceptable level, based on the value of the information
resource to the organization."
There are two things in this definition that may need
some clarification. First, the process of risk
management is an ongoing iterative process. It must be
repeated indefinitely. The business environment is
constantly changing and new threats and vulnerabilities
emerge every day. Second, the choice of countermeasures
(controls) used to manage risks must strike a balance
between productivity, cost, effectiveness of the
countermeasure, and the value of the informational asset
being protected.
Risk
is the likelihood that something bad will happen that
causes harm to an informational asset (or the loss of
the asset). A vulnerability is a weakness that
could be used to endanger or cause harm to an
informational asset. A threat is anything (man
made or act of nature) that has the potential to cause
harm.
The likelihood that a threat will use a vulnerability to
cause harm creates a risk. When a threat does use a
vulnerability to inflict harm, it has an impact. In the
context of information security, the impact is a loss of
availability, integrity, and confidentiality, and
possibly other losses (lost income, loss of life, loss
of real property). It should be pointed out that it is
not possible to identify all risks, nor is it possible
to eliminate all risk. The remaining risk is called
residual risk.
A risk assessment is carried out by a team of people who
have knowledge of specific areas of the business.
Membership of the team may vary over time as different
parts of the business are assessed. The assessment may
use a subjective qualitative analysis based on
informed opinion, or where reliable dollar figures and
historical information is available, the analysis may
use quantitative analysis.
The ISO/IEC 27002:2005 Code of practice for information
security management recommends the following be examined
during a risk assessment:
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security policy,
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organization of information security,
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asset management, human resources security,
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physical and environmental security,
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communications and operations management,
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access control,
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information systems acquisition,
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development and maintenance,
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information security incident management,
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business continuity management, and
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regulatory compliance.
In broad terms the risk management process consists of:
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Identification of assets and estimating their value.
Include: people, buildings, hardware, software, data
(electronic, print, other), supplies.
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Conduct a threat assessment. Include: Acts of
nature, acts of war, accidents, malicious acts
originating from inside or outside the organization.
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Conduct a vulnerability assessment, and for each
vulnerability, calculate the probability that it
will be exploited. Evaluate policies, procedures,
standards, training, physical security, quality
control, technical security.
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Calculate the impact that each threat would have on
each asset. Use qualitative analysis or quantitative
analysis.
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Identify, select and implement appropriate controls.
Provide a proportional response. Consider
productivity, cost effectiveness, and value of the
asset.
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Evaluate the effectiveness of the control measures.
Ensure the controls provide the required cost
effective protection without discernible loss of
productivity.
For any given risk, Executive Management can choose to
accept the risk based upon the relative low value
of the asset, the relative low frequency of occurrence,
and the relative low impact on the business. Or,
leadership may choose to mitigate the risk by
selecting and implementing appropriate control measures
to reduce the risk. In some cases, the risk can be
transferred to another business by buying insurance
or out-sourcing to another business. The reality of some
risks may be disputed. In such cases leadership may
choose to deny the risk. This is itself a
potential risk.
Controls
When Management chooses to mitigate a risk, they will do
so by implementing one or more of three different types
of controls.
Administrative
Administrative controls (also called procedural
controls) consist of approved written policies,
procedures, standards and guidelines. Administrative
controls form the framework for running the business and
managing people. They inform people on how the business
is to be run and how day to day operations are to be
conducted. Laws and regulations created by government
bodies are also a type of administrative control because
they inform the business. Some industry sectors have
policies, procedures, standards and guidelines that must
be followed - the Payment Card Industry (PCI) Data
Security Standard required by Visa and Master Card is
such an example. Other examples of administrative
controls include the corporate security policy, password
policy, hiring policies, and disciplinary policies.
Administrative controls form the basis for the selection
and implementation of logical and physical controls.
Logical and physical controls are manifestations of
administrative controls. Administrative controls are of
paramount importance.
Logical
Logical controls (also called technical controls) use
software and data to monitor and control access to
information and computing systems. For example:
passwords, network and host based firewalls, network
intrusion detection systems, access control lists, and
data encryption are logical controls.
An important logical control that is frequently
overlooked is the principle of least privilege.
The principle of least privilege requires that an
individual, program or system process is not granted any
more access privileges than are necessary to perform the
task. A blatant example of the failure to adhere to the
principle of least privilege is logging into Windows as
user Administrator to read Email and surf the Web.
Violations of this principle can also occur when an
individual collects additional access privileges over
time. This happens when employees' job duties change, or
they are promoted to a new position, or they transfer to
another department. The access privileges required by
their new duties are frequently added onto their already
existing access privileges which may no longer be
necessary or appropriate.
Physical
Physical controls monitor and control the environment of
the work place and computing facilities. They also
monitor and control access to and from such facilities.
For example: doors, locks, heating and air conditioning,
smoke and fire alarms, fire suppression systems,
cameras, barricades, fencing, security guards, cable
locks, etc. Separating the network and work place into
functional areas are also physical controls.
An important physical control that is frequently
overlooked is the separation of duties.
Separation of duties ensures that an individual can not
complete a critical task by himself. For example: an
employee who submits a request for reimbursement should
not also be able to authorize payment or print the
check. An applications programmer should not also be the
server administrator or the database administrator -
these roles and responsibilities must be separated from
one another.
Security classification for information
An important aspect of information security and risk
management is recognizing the value of information and
defining appropriate procedures and protection
requirements for the information. Not all information is
equal and so not all information requires the same
degree of protection. This requires information to be
assigned a security classification.
The first step in information classification is to
identify a member of senior management as the owner of
the particular information to be classified. Next,
develop a classification policy. The policy should
describe the different classification labels, define the
criteria for information to be assigned a particular
label, and list the required security controls for each
classification.
Some factors that influence which classification
information should be assigned include how much value
that information has to the organization, how old the
information is and whether or not the information has
become obsolete. Laws and other regulatory requirements
are also important considerations when classifying
information.
Common information security classification labels used
by the business sector are: public, sensitive,
private, confidential. Common information security
classification labels used by government are:
Unclassified, Sensitive But Unclassified,
Restricted, Confidential, Secret,
Top Secret and their non-English equivalents.
All employees in the organization, as well as business
partners, must be trained on the classification schema
and understand the required security controls and
handling procedures for each classification. The
classification a particular information asset has been
assigned should be reviewed periodically to ensure the
classification is still appropriate for the information
and to ensure the security controls required by the
classification are in place.
Access control
Access to protected information must be restricted to
people who are authorized to access the information. The
computer programs, and in many cases the computers that
process the information, must also be authorized. This
requires that mechanisms be in place to control the
access to protected information. The sophistication of
the access control mechanisms should be in parity with
the value of the information being protected - the more
sensitive or valuable the information the stronger the
control mechanisms need to be. The foundation on which
access control mechanisms are built start with
identification and authentication.
Identification
is an assertion of who someone is or what something is.
If a person makes the statement "Hello, my name is
John Doe." they are making a claim of who they are.
However, their claim may or may not be true. Before John
Doe can be granted access to protected information it
will be necessary to verify that the person claiming to
be John Doe really is John Doe.
Authentication
is the act of verifying a claim of identity. When John
Doe goes into a bank to make a withdrawal, he tells the
bank teller he is John Doe (a claim of identity). The
bank teller asks to see a photo ID, so he hands the
teller his driver's license. The bank teller checks the
license to make sure it has John Doe printed on it and
compares the photograph on the license against the
person claiming to be John Doe. If the photo and name
match the person, then the teller has authenticated that
John Doe is who he claimed to be.
There are three different types of information that can
be used for authentication: something you know,
something you have, or something you are. Examples
of something you know include such things as a
PIN, a password, or your mother's maiden name. Examples
of something you have include a driver's license
or a magnetic swipe card. Something you are
refers to biometrics. Examples of biometrics include
palm prints, finger prints, voice prints and retina
(eye) scans. Strong authentication requires providing
information from two of the three different types of
authentication information. For example, something you
know plus something you have. This is called two factor
authentication.
On computer systems in use today, the Username is the
most common form of identification and the Password is
the most common form of authentication. Usernames and
passwords have served their purpose but in our modern
world they are no longer adequate. Usernames and
passwords are slowly being replaced with more
sophisticated authentication mechanisms.
After a person, program or computer has successfully
been identified and authenticated then it must be
determined what informational resources they are
permitted to access and what actions they will be
allowed to perform (run, view, create, delete, or
change). This is called authorization.
Authorization to access information and other computing
services begins with administrative policies and
procedures. The polices prescribe what information and
computing services can be accessed, by whom, and under
what conditions. The access control mechanisms are then
configured to enforce these policies.
Different computing systems are equipped with different
kinds of access control mechanisms, some may offer a
choice of different access control mechanisms. The
access control mechanism a system offers will be based
upon one of three approaches to access control or it may
be derived from a combination of the three approaches.
The non-discretionary approach consolidates all access
control under a centralized administration. The access
to information and other resources is usually based on
the individuals function (role) in the organization or
the tasks the individual must perform. The discretionary
approach gives the creator or owner of the information
resource the ability to control access to those
resources. In the Mandatory access control approach,
access is granted or denied bases upon the security
classification assigned to the information resource.
Examples of common access control mechanisms in use
today include Role-based access control available in
many advanced Database Management Systems, simple file
permissions provided in the UNIX and Windows operating
systems, Group Policy Objects provided in Windows
network systems, Kerberos, RADIUS, TACACS, and the
simple access lists used in many firewalls and routers.
To be effective, policies and other security controls
must be enforceable and upheld. Effective policies
ensure that people are held accountable for their
actions. All failed and successful authentication
attempts must be logged, and all access to information
must leave some type of audit trail.
Cryptography
Information security uses cryptography to transform
usable information into a form that renders it unusable
by anyone other than an authorized user; this process is
called encryption. Information that has been encrypted
(rendered unusable) can be transformed back into its
original usable form by an authorized user, who
possesses the cryptographic key, through the process of
decryption. Cryptography is used in information security
to protect information from unauthorized or accidental
discloser while the information is in transit (either
electronically or physically) and while information is
in storage.
Cryptography provides information security with other
useful applications as well including improved
authentication methods, message digests, digital
signatures, non-repudiation, and encrypted network
communications. Older less secure application such as
telnet and ftp are slowly being replaced with more
secure applications such as ssh that use encrypted
network communications. Wireless communications can be
encrypted using the WPA or WEP protocols. Software
applications such as GNUPG or PGP can be used to encrypt
data files and Email.
Cryptography can introduce security problems when it is
not implemented correctly. Cryptographic solutions need
to be implemented using industry accepted solutions that
have undergone rigorous peer review by independent
experts in cryptography. The length and strength of the
encryption key is also an important consideration. A key
that is weak or too short will produce weak encryption.
The keys used for encryption and decryption must be
protected with the same degree of rigor as any other
confidential information. They must be protected from
unauthorized disclosure and destruction and they must be
available when needed. PKI solutions address many of the
problems that surround key management.
Defense in depth
Information security must protect information throughout
the life span of the information, from the initial
creation of the information on through to the final
disposal of the information. The information must be
protected while in motion and while at rest. During its
life time, information may pass through many different
information processing systems and through many
different parts of information processing systems. There
are many different ways the information and information
systems can be threatened. To fully protect the
information during its lifetime, each component of the
information processing system must have its own
protection mechanisms. The building up, layering on and
overlapping of security measures is called defense in
depth. The strength of any system is no greater than its
weakest link. Using a defence in depth strategy, should
one defensive measure fail there are other defensive
measures in place that continue to provide protection.
Recall the earlier discussion about administrative
controls, logical controls, and physical controls. The
three types of controls can be used to form the bases
upon which to build a defence-in depth-strategy. With
this approach, defence in depth can be conceptualised as
three distinct layers or planes laid one on top of the
other. Additional insight into defence in depth can be
gained by thinking of it as forming the layers of an
onion, with data at the core of the onion, people as the
outer layer of the onion, and network security,
host-based security and applications security forming
the inner layers of the onion. Both perspectives are
equally valid and each provides valuable insight into
the implementation of a good defence-in-depth strategy.
Process
The terms reasonable and prudent person, due
care and due diligence have been used in the
fields of Finance, Securities, and Law for many years.
In recent years these terms have found their way into
the fields of computing and information security. U.S.A.
Federal Sentencing Guidelines now make it possible to
hold corporate officers liable for failing to exercise
due care and due diligence in the management of their
information systems.
In the business world, stockholders, customers, business
partners and governments have the expectation that
corporate officers will run the business in accordance
with accepted business practices and in compliance with
laws and other regulatory requirements. This is often
described as the "reasonable and prudent person" rule. A
prudent person takes due care to ensure that everything
necessary is done to operate the business by sound
business principles and in a legal ethical manner. A
prudent person is also diligent (mindful, attentive, and
ongoing) in their due care of the business.
Attention should be made to two important points in
these definitions. First, in due care, steps are taken
to show - this means that the steps can be
verified, measured, or even produce tangible artifacts.
Second, in due diligence, there are continual
activities - this means that people are actually
doing things to monitor and maintain the protection
mechanisms, and these activities are ongoing.
Security governance
The Software Engineering Institute at Carnegie Mellon
University, in a publication titled "Governing for
Enterprise Security (GES)", defines characteristics of
effective security governance. These include:
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An Enterprise-wide Issue.
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Leaders are Accountable.
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Viewed as a Business Requirement.
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Risk-based.
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Roles, Responsibilities, and Segregation of Duties
Defined.
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Addressed and Enforced in Policy.
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Adequate Resources Committed.
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Staff Aware and Trained.
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A Development Life Cycle Requirement.
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Planned, Managed, Measurable, and Measured.
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Reviewed and Audited.
Incident response plans
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Selecting team members
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Define roles, responsibilities and lines of
authority
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Define a security incident
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Define a reportable incident
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Training
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Detection
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Classification
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Escalation
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Containment
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Eradication
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Documentation
Change management
Change management is a formal process for directing and
controlling alterations to the information processing
environment. This includes alterations to desktop
computers, the network, servers and software. The
objectives of change management are to reduce the risks
posed by changes to the information processing
environment and improve the stability and reliability of
the processing environment as changes are made. It is
not the objective of change management to prevent or
hinder necessary changes from being implemented.
Any change to the information processing environment
introduces an element of risk. Even apparently simple
changes can have unexpected effects. One of Managements
many responsibilities is the management of risk. Change
management is a tool for managing the risks introduced
by changes to the information processing environment.
Part of the change management process ensures that
changes are not implemented at inopportune times when
they may disrupt critical business processes or
interfere with other changes being implemented.
Not every change needs to be managed. Some kinds of
changes are a part of the everyday routine of
information processing and adhere to a predefined
procedure, which reduces the overall level of risk to
the processing environment. Creating a new user account
or deploying a new desktop computer are examples of
changes that do not generally require change management.
However, relocating user file shares, or upgrading the
Email server pose a much higher level of risk to the
processing environment and are not a normal everyday
activity. The critical first steps in change management
are (i) defining change (and communicating that
definition) and (b) defining the scope of the change
system.
Change management is usually overseen by a Change Review
Board comprised of representatives from key business
areas, security, networking, systems administrators,
Database administration, applications development,
desktop support and the help desk. The tasks of the
Change Review Board can be facilitated with the use of
automated work flow application. The responsibility of
the Change Review Board is to ensure the organizations
documented change management procedures are followed.
The change management process is as follows:
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Requested:
Anyone can request a change. The person making the
change request may or may not be the same person
that performs the analysis or implements the change.
When a request for change is received, it may
undergo a preliminary review to determine if the
requested change is compatible with the
organizations business model and practices, and to
determine the amount of resources needed to
implement the change.
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Approved:
Management runs the business and controls the
allocation of resources therefore, Management must
approve requests for changes and assign a priority
for every change. Management might choose to reject
a change request if the change is not compatible
with the business model, industry standards or best
practices. Management might also choose to reject a
change request if the change requires more resources
than can be allocated for the change.
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Planned
Planning a change involves discovering the scope and
impact of the proposed change; analyzing the
complexity of the change; allocation of resources
and, developing, testing and documenting both
implementation and backout plans. Need to define the
criteria on which a decision to back out will be
made.
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Tested:
Every change must be tested in a safe test
environment, which closely reflects the actual
production environment, before the change is applied
to the production environment. The backout plan must
also be tested.
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Implemented:
At the appointed date and time, the changes must be
implemented. Part of the planning process was to
develop an implementation plan, testing plan and, a
back out plan. If the implementation of the change
should fail or, the post implementation testing
fails or, other "drop dead" criteria have been met,
the back out plan should be implemented.
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Documented:
All changes must be documented. The documentation
includes the initial request for change, its
approval, the priority assigned to it, the
implementation, testing and back out plans, the
results of the change review board critique, the
date/time the change was implemented, who
implemented it, and whether the change was
implemented successfully, failed or postponed.
Change management procedures that are simple to follow
and easy to use can greatly reduce the overall risks
created when changes are made to the information
processing environment. Good change management
procedures improve the over all quality and success of
changes as they are implemented. This is accomplished
through planning, peer review, documentation and
communication.
ISO/IEC 20000, Visible Ops, and Information Technology
Infrastructure Library all provide valuable guidance on
implementing an efficient and effective change
management program.
Business Continuity The mechanism by which an
organization continues to OPERATE its CRITICAL BUSINESS
UNITS, during planned or unplanned DISRUPTIONS that
affect normal business operations, by invoking planned
and managed procedures… is called as Business
Continuity.
Unlike what most people think Business Continuity is not
necessarily an IT system or process, simply because it
is about the business. Today disasters or disruptions
are a reality. Whether the disaster is natural or
man-made (the TIME magazine has a website on the top
10), it affects normal life and so business. So why is
planning so important. Let us face reality that "all
businesses recover", whether they planned for recovery
or not, simply because business is about earning money
for survival.
The planning is merely getting better prepared to face
it, knowing fully well that the best plans may fail.
Planning helps to reduce cost of recovery, operational
overheads and most importantly sail through some smaller
ones effortlessly.
For businesses to create effective plans they need to
focus upon the following key questions. Most of these
are common knowledge, and anyone can do a BCP.
1. Should a disaster strike, what are the first few
things that I should do? Should I call people to find if
they are OK or call up the bank to figure out my money
is safe......This is Emergencey Response. Emergency
Response services help take the first hit when the
disaster strikes and if the disaster is serious enough
the Emergency Response teams need to quickly get a
Crisis Management team in place. 2. What part of my
business should I recover first? These are the critical
business units...The one that brings me most money or
the one where I spend the most, or the one that will
ensure I shall be able to get sustained future
growth.... There is no magic bullet here, no one answer
satisfies all. Businesses need to find answers that meet
business requirements. 3. How soon should I target to
recover my critical business units? In BCP technical
jargonism this is called Recovery Time Objective (RTO).
And this one will define what costs the business will
need to spend to recover.... For example, it is cheaper
to recover a business in 1 day than in 1 hour. 4. What
all do I need to recover the business? IT, machinery,
records...food, water, people...So many aspects to dwell
upon. The cost factor becomes clearer now...Business
leaders need to drive business continuity. Hold on. My
IT manager spent $200000 last month and created a DRP
(Disaster Recovery Plan), whatever happened to that? a
DRP is about continuing an IT system, and is one of the
sections of a comprehensive Business Continuity Plan.
Look below for more on this. 5. And where do I recover
my business from... Will the business center give me
space to work, or would it be flooded by many people
queuing up for the same reasons that I am. 6. But once I
do recover from the disaster and work in reduced
production capacity, since my main operational sites are
unavailable, how long can this go on. How long can I do
without my original sites, systems, people? this defines
the amount of business resilience a business may have.
7. Now that I know how to recover my business. How do I
make sure my plan works? Most BCP pundits would
recommend testing the plan at least once a year,
reviewing it for adequacy and rewriting or updating the
plans either annually or when businesses change.
Disaster recovery planning
Disaster Recovery Planning is all about continuing an IT
service. You need 2 or more sites, one of them is
primary, which is planned to be recovered. The alternate
site may be online...meaning production data is
simultaneously transferred to both sites (sometime
called as HOT Sites), may be offline...meaning data is
tranferred after a certain delay through other means,
(sometimes called as a WARM site) or even may not be
transferred at all, but may have a replica IT system of
the original site, which will be started whenever the
primary site faces a disaster (sometimes called a COLD
site).
Though DRP is part of the BCP process, DRP focusses on
IT systems recovery and BCP on the entire business.
DRP is one of the recovery activities during execution
of a Business Continuity Plan.