Information Security and ISO27001 – an Introduction
Overview
What is ISO 27001 (BS7799), and how does this standard help organizations more effectively
manage their information security? What's the relationship between ISO 27001 (BS7799) and
ISO 17799, how can it relate to ISO 9001, and what does someone coming to this field for the
first time need to know in order to initiate, or take on responsibility for, an organizational
information security project, and specifically one that is intended to lead to ISO 27001
(BS7799) certification? This paper, written by the ISO 27001/BS7799 expert Alan Calder,
answers these basic questions and others and points to online resources and tools that are
useful to anyone tasked with leading an information security project. The information in this
paper is suitable for all sizes of organizations, and all sectors, anywhere in the world. It
reflects the guidance and information available from The ISO27001 Site, which can be
accessed through http://www.itgovernance.co.uk/iso27001.asp
IT Governance and information security
The last few years have seen board corporate governance requirements increasingly more
defined and specific. As information technology has become pervasive, underpinning and
supporting almost every aspect of the organization, manipulating and storing the information
on which the organization depends for its survival, so the role of IT in corporate governance
has become more clearly defined and IT governance is increasingly recognised as a specific
area for board and corporate attention. A fundamental aspect of IT governance is the
protection of the information – its availability, confidentiality and integrity – on which
everything else depends.
In parallel, international standards related to information security have emerged and have
become one of the cornerstones of an effective IT governance framework.
The information security standards
BS7799 was created in 1995, by the British Standards Institution (BSI), as a standard to guide
the development and implementation of an Information Security Management System,
commonly known as an ISMS. BS7799 was conceived, from the outset, as a technology-
neutral, vendor-neutral management system that, properly implemented, would enable an
organization's management to assure itself that its information security measures and
arrangements were effective.
From the outset, BS7799 focused on protecting the availability, confidentiality and integrity
of organizational information and this remains, today, the driving objective of the standard.
Crucially though, it doesn't talk about protection from every single possible threat, but only
from those that the organization considers relevant and only to the extent that is justified
financially and commercially through a risk assessment.
BS7799 was originally just a single standard, and had the status of a Code of Practice. In
other words, it provided guidance for organizations, but hadn't been written as specification
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that could form the basis of an external third party verification and certification scheme. As
more and more organizations began to recognize the scale, severity and interconnectedness of
information security threats, and with the emergence of a growing range of data protection
and privacy-related law and regulation, so the demand for a certification option linked to the
standard began to develop.
This led, eventually, to the emergence of a second part to the standard, in the form of a
specification (a specification uses words like ‘shall’) numbered as BS7799-2 (or, part 2). The
Code of Practice (which uses words like ‘may’ and which deals with controls, not with
Information Security Management Systems), is now recognized under the dual numbers of
ISO17799 and BS7799-1 (or, part 1). The relationship between the Code of Practice and the
specification was also established at this time: a specification is the basis for certification
schemes and ISO 27001 mandates the use of ISO 17799 as the source of guidance for the
selection and implementation of the controls mandated by ISO 27001. In effect, ISO 17799 is
the second part of ISO 27001.
The most recent version of the Code of Practice, and the one which must be used, is ISO/IEC
17799:2005. BS7799-2:2002 has also undergone revision and internationalisation, and was
replaced in November 2005 by ISO/IEC 27001:2005. BS7799-2:2002 has now been
withdrawn. The best way to keep in touch with the changes to the standards is to subscribe to
24743, the free information security newsletter that provides regularly updated FAQs on the
new standards, as well as other ISMS information. Online subscription for 24743 is available
here: http://www.itgovernance.co.uk/page.bs7799
The information security standards are the essential starting point for any organization that is
commencing an information security project. Anyone contemplating such a project should
purchase and study copies of both standards, which are available for online purchase in a
money-saving kit, in either hard copy or electronic format, from here:
http://www.itgovernance.co.uk/products/32.
Various countries have published their own versions of the British standards and they appear,
for instance, as AS/NZS 7799. The international versions of these standards, which can be
certified anywhere in the world, are likely to lead to the disappearance of local versions, other
than on a dual-numbering basis. It should also be noted that there are a number of sector-
specific schemes, in which a specific industrial sector has developed its own version of
BS7799 to reflect its specific concerns and issues. An example of this is the scheme
developed in the UK by APACS.
The information security and regulatory environments
The two key reasons for the growing interest in certification to ISO 27001 are the
proliferation of threats to information and the growing range of regulatory and statutory
requirements that relate to information protection.
Information security threats are global in nature, and indiscriminately target every
organization and individual who owns or uses (primarily) electronic information. These
threats are automated and loose on the internet. In addition, data is exposed to many other
dangers, from acts of nature, through external attack to internal corruption and theft.
The last ten years have also seen the emergence of a growing body of legislation and
regulation around information and data security, some aimed at ensuring that individual data
is protected and some aimed at ensuring that corporate financial, operational and risk
management systems are appropriately underpinned. A formal information security
management system, that provides guidance for the deployment of best practice, is
increasingly seen as a necessity in compliance terms and certification is increasingly required
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of organizations (and governments) before they will engage in any significant commercial
transactions with potential new suppliers. The implications of this for the outsourcing
industry are self evident. The argument for deployment of a formal ISMS are fully developed
in a short book called The Case for ISO 27001. This book, which is available online as an
eBook from http://www.itgovernance.co.uk/products/149, (a soft cover version is also
available) is also designed to provide a project manager with the arguments that may be
necessary to get the organization's board to make the appropriate commitment to the project.
Certification vs conformance
It is possible for an organization to develop its ISMS in line with ISO17799 only, because the
good practice identified in this Code of Practice is universally applicable. However, because
it was not designed to be the basis of a certification scheme, it doesn't specify the system
requirements with which an ISMS must be compliant if it is to be so certified. ISO/EC 27001
does contain those specifications. In technical terms, this means that an organization that is
using ISO17799 on its own can conform to the guidance of the Code of Practice but it cannot
get an outside body to verify that it is complying with the standard. An organization that is
using ISO27001 and ISO17799 in conjunction with one another can design an ISMS that is in
line with the specification and which follows the guidance of the Code of Practice and which
is therefore capable of achieving external certification.
Certification and other management standards
ISO27001 is designed to be compatible with other management standards such as ISO9000
and ISO14001. It is also compatible with ISO/IEC 20000:2005. The numbering systems and
document management requirements are designed to be compatible and to enable
organizations to develop management systems that integrate to as great an extent as possible
the requirements of each of the management standards that the organization is using.
Generally speaking, organizations should seek ISO27001 certification from the certification
body they currently use for certifying their ISO9000 or other management system. The
experience of the organization's quality manager in this process will be invaluable to the
ISMS project.
There is no reason, however, why organizations shouldn't tackle ISO27001 without having
first implemented any other form of management system. In that case, they will choose a
certification body on a commercial basis from amongst those available and operating in their
country. A certification body must be accredited by a national accreditation body for it to be
allowed to carry our accredited certifications and to award the relevant badge that formally
signifies certification. Most countries have their own accreditation services (in the UK, for
instance, it is UKAS) and these will all maintain lists of the organizations who are accredited
for ISMS certifications. The website has links
(http://www.itgovernance.co.uk/page.web_links) to the major international certification
organizations.
Information security and technology
Most people think of information security as a technology issue. They think that anything to
do with securing data or protecting computers from threats is something that only technology
people – and specifically computer security people – can deal with. Nothing could be further
from the truth. The reality is that it is the computer user who should make decisions about
which threats to be protected from and what trade-offs between security and flexibility he or
she is prepared to accept. Yes, once these decisions have been made, the computer security
expert should design and implement a technological solution that delivers these results.
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In an organizational environment, those decisions should be made the management team, not
by the IT team. An ISMS overtly and specifically recognizes that decision-making
responsibility should sit with the organization's board and management, and that the ISMS
should reflect their choices and provide evidence as to the effectiveness with which they have
been carried out.
As a result, it is not necessary for an ISMS project to be led by a technology expert. In fact,
there are many circumstances in which that could be counter-productive. These projects are,
often, led by quality managers, general managers or other executive who is in a position to
develop something that has organization-wide influence and importance.
Preparing for an ISMS project and the PDCA cycle
An ISMS project can be a complex one. It is likely to encompass the entire organization, it
should involve everyone from the management down to the post room operatives, and it may
well take many months – and, in some cases, years. ISO27001 certification is still relatively
new and, as a result, hard experience of successful implementations is in short supply. This
means that the handful of publications that describe, from a practical and pragmatic point of
view, how to go about achieving certification, should be studied at an early point in the
project planning process.
The two most relevant books are, firstly, Nine Steps to 27001 Success: an Implementation
Overview (http://www.itgovernance.co.uk/products/151) and, secondly, IT Governance: a
Manager's Guide to Data Security and BS7799/ISO17799
(http://www.itgovernance.co.uk/products/4). The first book (available in both eBook and soft
cover formats) is a short but thorough overview of the steps that are critical to success, while
the second (which is also the Open University’s post-graduate information security textbook)
is a detailed and widely used practical guide to implementing a certified ISMS which was
written for non-technical readers and is now in its third edition. It is web-enabled and gives
its readers free access to an online KnowledgeBank of specialist and current information
related to ISMS implementations.
ISO27001 sets out how an organization should approach its ISMS project and specifies the
components that are essential. You can download a free PowerPoint presentation and other
resources from http://www.itgovernance.co.uk/files/The_Complete_ISMS_Toolkit.pdfthat provide an overview of the
ISMS project, the time line and the various options for how you might tackle it. As you will
see, there are specified stages to the project and what is called the PDCA cycle must be
followed.
The PDCA cycle is the Plan-Do-Check-Act cycle that was originated in the 1950s by W.
Edwards Deming and which says that that business processes should be treated as though
they are in a continuous feedback loop so that managers can identify and change those parts
of the process that need improvement. The process, or an improvement to the process, should
first be planned, then implemented and its performance measured, then the measurements
should be checked against the planned specification and any deviations or potential
improvements identified, and reported to management for a decision about what action to
take.
Risk assessment and risk treatment plans
An ISMS must be developed and designed to meet the individual requirements of each
organization. Not only does every organization have its own specific business model,
objectives, unique selling features and culture, it also has its different appetites for risk. In
other words, something that one organization sees as a threat against which it must guard,
another might see that same threat as an opportunity that it should grasp. Similarly, one
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organization might be less prepared to invest in defences against an identified risk than
another. For this, and other reasons, every organization that implements an ISMS must do so
against the findings of a risk assessment whose methodology, findings and recommendations
have been approved by the board of directors. While there are only a few standard methods of
assessing and measuring risk, there are a number of tools for simplifying and automating the
process. IT Governance: a Manager's Guide to Data Security and BS7799/ISO17799
(http://www.itgovernance.co.uk/products/4) has an extensive chapter on risk assessment.
The recently published risk assessment standard, BS7799-3, provides guidance on risk
assessment (http://www.itgovernance.co.uk/products/162), and there is a current guide to risk
assessment tools in the KnowledgeBank. The most useful risk assessment tool, and one
which conforms closely to the requirements of both ISO 27001 and BS7799-3 is called RA2.
This product, available on CD-Rom, can quickly and easily be deployed on the desktop.
More information is at: http://www.itgovernance.co.uk/products/165
System documentation
The most time-consuming, but most critical part of the entire project is the development of
the documentation that sets out how the ISMS works. There are a number of different
possible approaches to this, from using external consultants to tackling it yourself. The major
argument in favour of doing it yourself (apart from avoiding, or reducing, consultancy costs)
is that you will develop in your organization a much greater depth and awareness of 'how to
do security'. However, without previous experience, development of all the documentation
required can be a daunting task, unless you deploy a pre-completed, templated documentation
toolkit, like the one that can be found at http://www.itgovernance.co.uk/page.free_trial. This
page provides access to an option so that the toolkit (which is linked to IT Governance: a
Manager's Guide to Data Security and BS7799/ISO17799) can be trialled for free, and also
provides other information and resources around documentation.
Policy Management
All organizations face the challenge of effectively deploying their ISMS documentation,
ensuring that it is properly controlled, that it is accessible to everyone who needs to see it,
and that there is evidence that users have read and understood all those policies that apply to
them. This sort of audit trail is becoming increasingly important as information-related
regulation becomes more wide-spread. The most practical way of dealing with all the policy-
management challenges is to deploy a policy management tool. There is more information
about these tools here: http://www.itgovernance.co.uk/products/156.
Consultants and consultancy services
There are many circumstances under which organizations decide that they want to do more
than simply 'do it themselves'. This is the point at which they need access to a range of
tailored and focused services, from health checks through to tailored interventions. It is
critical that, if you're going to work with consultants, you choose people who have done it all
before, many times. Here is some information, together with contact details, about the types
of services that might be useful: http://www.itgovernance.co.uk/page.service
ISMS Resources
The ISO27001 Site
http://www.itgovernance.co.uk/page.bs7799
Information security standards online
http://www.itgovernance.co.uk/products/32
Risk assessment standard
http://www.itgovernance.co.uk/products/162
Risk assessment tool RA2
http://www.itgovernance.co.uk/products/165
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Policy management tools
http://www.itgovernance.co.uk/products/156.
The Case for ISO 27001
http://www.itgovernance.co.uk/products/149
Nine Steps to ISO 27001 Success: an Implementation Overview
http://www.itgovernance.co.uk/products/151
IT Governance: a Manager's Guide to Data Security
and BS7799/ISO1779
http://www.itgovernance.co.uk/products/4
Links to Certification Bodies
http://www.itgovernance.co.uk/page.web_links
27001 ISMS Documentation Toolkit
http://www.itgovernance.co.uk/page.free_trial
Consultancy Services
http://www.itgovernance.co.uk/page.service
Contact details
IT Governance Ltd
66 Silver Street
Ely
Cambs CB7 4JB
UK
T: + 44 845 170 1750
E: info@itgovernance.co.uk
W: http://www.itgovernance.co.uk/


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