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Tags: applicability, automated information systems, course content, executive secretariat, fort george g meade md, government agency, government contractors, information systems ais, information systems security, manager telecommunications, mcconnell, national security agency, nstiss, officer representative, security committee, security foreword, security national, telecommunications security, u s navy, vice admiral,
Pages: 29
Language: english
Created: Wed Aug 5 09:55:49 1998
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                                     NSTISSI No. 4011
                                      20 June 1994



NSTISS
NATIONAL
SECURITY
TELECOMMUNICATIONS
AND
INFORMATION
SYSTEMS
SECURITY




                     NATIONAL TRAINING STANDARD
                      FOR INFORMATION SYSTEMS
                         SECURITY (INFOSEC)
                           PROFESSIONALS
NSTISS
NATIONAL SECURITY
                           NATIONAL MANAGER
TELECOMMUNICATIONS
AND INFORMATION
SYSTEMS SECURITY




                                   FOREWORD




         1. This instruction provides the minimum course content for the training
  of information systems security (INFOSEC) professionals in the disciplines of
  telecommunications security and automated information systems (AIS) security.

        2. Representatives of the National Security Telecommunications and
  Information Systems Security Committee may obtain additional copies of this
  instruction from:

           Executive Secretariat
           National Security Telecommunications and
              Information Systems Security Committee
           National Security Agency
           Fort George G. Meade, MD 20755-6000

         3. U.S. Government contractors are to contact their appropriate
  government agency or Contracting Officer Representative regarding distribution
  of this document.




                               J. M. McCONNELL
                             Vice Admiral, U.S. Navy
                                                   NSTISSI No. 4011




                  NATIONAL TRAINING STANDARD
                              FOR
     INFORMATION SYSTEMS SECURITY (INFOSEC) PROFESSIONALS



                                                                       SECTION
         PURPOSE . . . . . . . .   .   .   .   .   .   .   .   .   .      I
         SCOPE AND APPLICABILITY   .   .   .   .   .   .   .   .   .     II
         REFERENCES. . . . . . .   .   .   .   .   .   .   .   .   .    III
         RESPONSIBILITIES. . . .   .   .   .   .   .   .   .   .   .     IV
         TRAINING STANDARD . . .   .   .   .   .   .   .   .   .   .      V


                     SECTION I - PURPOSE

    1. This instruction establishes the minimum training
standard for the training of information systems security
(INFOSEC) professionals in the disciplines of telecommuni-
cations and automated information systems (AIS) security.


             SECTION II - SCOPE AND APPLICABILITY

    2. National Security Telecommunications and Information
Systems Security Directive No. 501 establishes the
requirement for federal departments and agencies to implement
training programs for INFOSEC professionals. As defined in
NSTISSD 501, an INFOSEC professional is an individual who is
responsible for the security oversight or management of
national security systems during phases of the life cycle.
That directive is being implemented in a synergistic
environment among departments and agencies which are
committed to satisfying these INFOSEC education and training
requirements in the most effective and efficient manner
possible. This instruction is the first in a series of
minimum training and education standards which are being
developed to assist departments and agencies in meeting their
responsibilities in these areas.
                                          NSTISSI No. 4011



    3. The body of knowledge listed in this instruction may
be obtained from a variety of sources, i.e., the National
Cryptologic School, contractors, adaptations of existing
department/agency training programs, or a combination of
experience and formal training.

    4. This instruction is applicable to all departments and
agencies of the U.S. Government, their employees, and contractors
who are responsible for the security oversight or management of
national security systems during each phase of the life cycle.


                   SECTION III - REFERENCES

    5. P.L. 100-235, Computer Security Act of 1987, dated
January 8, 1988.

    6. National Policy for the Security of National Security
Telecommunications and Information Systems, dated July 5, 1990.

    7. NSTISSD 501, National Training Program for Information
Systems Security (INFOSEC) Professionals, dated
16 November 1992.
    8. OMB Circular A-130, Appendix III, Security of Federal
Automated Information Systems, December 12, 1985.

    9. Office of Personnel Management, 5 CFR Part 930, Train-
ing Requirements for the Computer Security Act, January 3,
1992.

   10. NSTISSI No. 4009, National Information Systems Security
(INFOSEC) Glossary, June 5, 1992.


                 SECTION IV - RESPONSIBILITIES

  11.   Heads of U.S. Government departments and agencies will:

        a. Ensure that INFOSEC professionals obtain the body
of knowledge as outlined in this instruction.

        b. Ensure that an INFOSEC training program is an
integral part of the overall training program.
                                           NSTISSI No. 4011


        c. Require contractors to comply with the provisions
of this instruction when they are responsible for the security
oversight or management of national security systems operated
by or on behalf of the U.S. Government.

   12.   The National Manager will:

        a. Provide and maintain an INFOSEC training standard
to U.S. Government departments and agencies.

        b. Ensure that appropriate INFOSEC training courses
are developed.

        c. Assist other U.S. Government departments and
agencies in developing and/or conducting INFOSEC training
activities as requested.


                  SECTION V - TRAINING STANDARD

   13. Using a comprehensive model of information systems
security, the curriculum is intended to provide two levels of
knowledge:

        a. Awareness Level. Creates a sensitivity to the
threats and vulnerabilities of national security information
systems, and a recognition of the need to protect data, infor-
mation and the means of processing them; and builds a working
knowledge of principles and practices in INFOSEC.

        b. Performance Level. Provides the employee with the
skill or ability to design, execute, or evaluate agency INFOSEC
security procedures and practices. This level of understanding
will ensure that employees are able to apply security concepts
while performing their tasks.

   14. The program of instruction, as outlined below, shall
encompass scope, suggested sequence, and content.

         a.   COMMUNICATIONS BASICS (Awareness Level)

  Instructional Content           Behavioral Outcomes

- Introduce the evolution of   - Outline chronology of
  modern communications systems. communications systems and
                                  development.
                                              NSTISSI No. 4011


- Describe vehicles of           - Match features of trans-
  transmission.                    mission to descriptors
                                   (e.g., signal type, speed
                                   production characteristics,
                                   etc.)

              (1)   Topical Content

                    (a) Historical vs Current Methodology

                    (b) Capabilities and limitations of various
                        communications systems
                        - microwave
                        - line of sight
                        - satellite
                        - radio frequency (e.g., bandwidth)
                        - asynchronous vs synchronous
                        - dedicated line
                        - digital vs analog
                        - public switched network

              (1)   Topical Content

                    (a) Historical vs Current Methodology
        b.    AUTOMATED INFORMATION SYSTEMS (AIS) BASICS
             (Awareness Level)

  Instructional Content                 Behavioral Outcomes

- Provide language of an AIS.         - Define terms in an AIS.

- Describe an AIS environment         - Define functions performed.
  by an AIS.

- Providing an overview of            - Describe interrelationship
  hardware, software, firmware          among AIS components.
  components of an AIS, to
  integrate into information
  systems security aspects/
  behaviors discussed later.
                                              NSTISSI No. 4011


             (1)   Topical Content

                   (a) Historical vs Current Technology

                   (b) Hardware
                       - distributed vs stand-alone
                       - micro, mini, mainframe processors
                       - storage devices
                      - components (e.g., input, output, central
                         processing unit (CPU))

                   (c) Software
                       - operating system
                       - applications

                   (d) Memory
                       - sequential
                       - random
                       - volatile vs nonvolatile

                   (e) Media
                       - magnetic remanence
                       - optical remanence

                   (f) Networks
                       - topology
                       - sharing of data
                       - sharing of devices
                       - file servers
                       - modems
                       - asynchronous vs synchronous
                       - switching

        c.   SECURITY BASICS (Awareness Level)

  Instructional Content              Behavioral Outcomes

- Using the Comprehensive Model   - The student will list and
  of Information Systems Security   describe the elements of
  (contained in the Annex to        AIS security.
  this instruction), introduce
  a comprehensive model of        - The student will summarize
  information systems security      security disciplines used
  that addresses:                   in protecting government
                                     automated information
  - critical characteristics        systems.
    of information
                                        NSTISSI No. 4011

- information states, and         - Student will give examples
- security measures.                 of determinants of criti-
                                     cal information.


          (1)   Topical Content

                (a) INFOSEC Overview
                    - threats
                    - vulnerabilities
                    - critical information characteristics
                      - confidentiality
                      - integrity
                      - availability
                    - information states
                      - transmission
                      - storage
                      - processing
                    - security countermeasures
                      - technology
                      - policy, procedures and practices
                      - education, training and awareness
                (b) Operations Security (OPSEC)
                    - OPSEC process
                    - INFOSEC and OPSEC interdependency
                    - unclassified indicators
                    - OPSEC surveys/OPSEC planning

                (c) Information Security
                    - policy
                    - roles and responsibilities
                    - application dependent guidance

                (d) INFOSEC
                    - cryptography
                      - strength (e.g., complexity, secrecy,
                         characteristics of the key)
                      - encryption (e.g., point-to-point,
                         network, link)
                      - key management (to include electronic
                         key)
                    - transmission security
                    - emanations security
                                           NSTISSI No. 4011



                      - physical, personnel and administrative
                        security
                      - computer security
                        - identification and authentication
                        - access control
                        - audit
                        - object reuse

        d.   NSTISS BASICS (Awareness Level)

 Instructional Content                 Behavioral Outcomes

- Describe components (with          - Outline national NSTISS
  examples to include: national        Policies.
  policy, threats and vulner-
  abilities, countermeasures,        - Cite examples of threats
  risk management, systems             and vulnerabilities of an
  lifecycle management, trust,         AIS.
  modes of operation, roles of
  organizational units, facets       - Give examples of Agency
  of NSTISS.                           implementation of NSTISS
                                        policy, practices and
                                        procedures.

             (1)   Topical Content

                   (a) National Policy and Guidance
                       - AIS security
                       - communications security
                       - protection of information
                       - employee accountability for
                         agency information

                   (b) Threats to and Vulnerabilities of Systems
                       - definition of terms (e.g., threats,
                         vulnerabilities, risk)
                       - major categories of threats (e.g.,
                         fraud, Hostile Intelligence Service
                         (HOIS), malicious logic, hackers,
                        environmental and technological hazards,
                         disgruntled employees, careless
                         employees, HUMINT, and monitoring)
                       - threat impact areas
                        NSTISSI No. 4011



(c) Legal Elements
    - fraud, waste and abuse
    - criminal prosecution
    - evidence collection and preservation
    - investigative authorities

(d) Countermeasures
    - cover and deception
    - HUMINT
    - monitoring (e.g., data, line)
    - technical surveillance countermeasures
    - education, training, and awareness
   - assessments (e.g., surveys, inspections)

(e) Concepts of Risk Management
    - threat and vulnerability assessment
    - cost/benefit analysis of controls
    - implementation of cost-effective
       controls
    - consequences (e.g., corrective action,
       risk assessment)
    - monitoring the efficiency and effective-
       ness
       of controls (e.g., unauthorized or
       inadvertent disclosure of information)

(f) Concepts of System Life Cycle Management
    - requirements definition (e.g.,
      architecture)
    - development
    - demonstration and validation (testing)
    - implementation
    - security (e.g., certification and
      accreditation)
    - operations and maintenance (e.g.,
      configuration management)

(g) Concepts of Trust
    - policy
    - mechanism
    - assurance

(h) Modes of Operation
    - dedicated
    - system-high
    - compartmented/partitioned
    - multilevel
                                          NSTISSI No. 4011



                  (i) Roles of Various Organizational Personnel
                      - senior management
                      - program or functional managers
                      - system manager and system staff
                      - telecommunications office and staff
                      - security office
                      - COMSEC custodian
                      - INFOSEC Officer
                      - information resources management staff
                      - audit office
                      - OPSEC managers
                      - end users

                  (j) Facets of NSTISS
                      - protection of areas
                      - protection of equipment
                      - protection of passwords
                      - protection of files and data
                      - protection against malicious logic
                      - backup of data and files
                      - protection of magnetic storage media
                      - protection of voice communications
                      - protection of data communications
                      - protection of keying material
                      - application of cryptographic systems
                      - transmission security countermeasures
                       (e.g., callsigns, frequency, and pattern
                        forewarning protection)
                      - reporting security violations

        e.   SYSTEM OPERATING ENVIRONMENT (Awareness Level)

  Instructional Content                Behavioral Outcomes

- Outline Agency specific            - Summarize Agency AIS
  AIS and telecommunications           and telecommunications
  systems.                             systems in operation.

- Describe Agency "control points"   - Give examples of current
  for purchase and maintenance         Agency AIS/telecom-
  of Agency AIS and telecommuni-       munications systems and
  cations systems.                     configurations.
                                            NSTISSI No. 4011



- Review Agency AIS and telecom-      - List Agency-level contact
  munications security policies.        points for AIS and tele-
                                         communications systems
                                        and maintenance.
                                      - Cite appropriate policy
                                        and guidance.

             (1)   Topical Content

                   (a) AIS
                       - hardware
                       - software
                       - firmware
                   (b) Telecommunications Systems
                       - hardware
                       - software

                   (c) Agency Specific Security Policies
                       - guidance
                       - roles and responsibilities
                       - points of contact

                   (d) Agency Specific AIS and Telecommunications
                        Policies
                        - points of contact
                        - references

        f.   NSTISS PLANNING AND MANAGEMENT (Performance Level)

  Instructional Content                Behavioral Outcomes

- Discuss practical performance      - Builds a security plan
  measures employed in designing       that encompasses NSTISS
  security measures and programs.      components in designing
                                       protection/security for an
- Introduce generic security           instructor-supplied
  planning guidelines/documents.       description of an AIS
                                       telecommunications system.
                              NSTISSI No. 4011



(1)   Topical Content

      (a) Security Planning
          - directives and procedures for NSTISS
            policy
          - NSTISS program budget
          - NSTISS program evaluation
          - NSTISS training (content and audience
            definition)

      (b) Risk Management
          - information identification
          - roles and responsibilities of all the
            players in the risk analysis process
          - risk analysis and/or vulnerability
            assessment components
          - risk analysis results evaluation
          - corrective actions
          - acceptance of risk (accreditation)
      (c) Systems Life Cycle Management
         - management control process (ensure that
            appropriate administrative, physical,
            and technical safeguards are incor-
            porated into all new applications and
            into significant modifications to
            existing applications)
          - evaluation of sensitivity of the
            application based upon risk analysis
         - determination of security specifications
          - design review and systems test
            performance (ensure required safeguards
            are operationally adequate)
         - systems certification and accreditation
            process
          - acquisition

      (d) Contingency Planning/Disaster Recovery
          - contingency plan components
          - agency response procedures and
            continuity of operations
                                           NSTISSI No. 4011


                       - team member responsibilities in
                         responding to an emergency situation
                       - guidelines for determining critical and
                         essential workload
                       - determination of backup requirements
                       - development of procedures for off-site
                         processing
                       - development of plans for recovery
                         actions after a disruptive event
                       - emergency destruction procedures

        g.   NSTISS POLICIES AND PROCEDURES (Performance Level)

  Instructional Content                Behavioral Outcomes

- List and describe:                 - Playing the role of either
  specific technological, policy,      a system penetrator or
  and educational solutions            system protector, the
  for NSTISS.                           student will discover
                                        points of exploitation
- List and describe:                   and apply appropriate
  elements of vulnerability and        countermeasures in an
  threat that exist in an AIS/         instructor-supplied
  telecommunications system with       description of an Agency
  corresponding protection             AIS/telecommunications
  measures.                            system.

             (1)   Topical Content

                   (a) Physical Security Measures
                       - building construction
                       - alarms
                       - information systems centers
                       - communications centers
                       - shielding
                       - cabling
                       - filtered power
                       - physical access control systems (key
                         cards,
                         locks and alarms)
                       - stand-alone systems and peripherals
                      - environmental controls (humidity and air
                         conditioning)
                       - fire safety controls
                       - storage area controls
                      - power controls (regulator, uninterrupted
                         power service (UPS), and emergency
                         poweroff switch)
                       - protected distributed systems
                        NSTISSI No. 4011



(b) Personnel Security Practices and
    Procedures
    - position sensitivity
    - employee clearances
    - access authorization/verification
      (need-to-know)
   - security training and awareness (initial
      and refresher)
    - systems maintenance personnel
    - contractors

(c) Software Security
    - configuration management
       - programming standards and controls
       - documentation
       - change controls
    - software security mechanisms to protect
       information
       - segregation of duties
       - concept of least privilege
       - identification and authentication
       - access privileges
       - internal labeling
       - application security features
       - audit trails and logging
       - operating systems security features
       - need-to-know controls
       - malicious logic protection
     - assurance

(d) Network Security
    - public vs private
    - dial-up vs dedicated
    - privileges (class, nodes)
    - traffic analysis
    - end-to-end access control
                        NSTISSI No. 4011



(e) Administrative Security Procedural
    Controls
    - external marking of media
    - destruction of media
    - sanitization of media
    - construction, changing, issuing and
      deleting passwords
    - transportation of media
    - reporting of computer misuse or abuse
    - preparation of security plans
    - emergency destruction
    - media downgrade and declassification
    - copyright protection and licensing
    - documentation, logs and journals
    - attribution
    - repudiation

(f) Auditing and Monitoring
    - effectiveness of security programs
    - conducting security reviews
    - verification, validation, testing, and
      evaluation processes
    - monitoring systems for accuracy and
      abnormalities
    - investigation of security breaches
    - review of audit trails and logs
    - review of software design standards
    - review of accountability controls
    - privacy

(g) Cryptosecurity
   - encryption/decryption method, procedure,
      algorithm
    - cryptovariable or key
    - electronic key management system

(h) Key Management
    - identify and inventory COMSEC material
    - access, control and storage of COMSEC
      material
    - report COMSEC incidents
    - destruction procedures for COMSEC
      material
    - key management protocols (bundling,
      electronic key, over-the-air rekeying)
                                          NSTISSI No. 4011



                 (i) Transmission Security
                     - frequency hopping
                     - masking
                     - directional signals
                     - burst transmission
                     - optical systems
                     - spread spectrum transmission
                     - covert channel control (crosstalk)
                     - dial back
                     - line authentication
                     - line-of-sight
                     - low power
                     - screening
                     - jamming
                     - protected wireline

                 (j) TEMPEST Security
                     - shielding
                     - grounding
                     - attenuation
                     - banding
                     - filtered power
                     - cabling
                     - zone of control/zoning
                     - TEMPEST separation

Enclosure:
  Information Systems Security:   A Comprehensive Model
                              ANNEX
                                                              1
     INFORMATION SYSTEMS SECURITY:    A COMPREHENSIVE MODEL


                          INTRODUCTION
    This Annex serves as a comprehensive model for the security
of information systems and also functions as an assessment,
systems development, and evaluation tool. The model is unique in
that it stands independent of technology. Its application is
universal and is not constrained by organizational differences.
As with all well-defined fundamental concepts, it is unnecessary
to alter the premise even as technology and human understanding
evolve.
    Computers communicate. Communications systems compute. The
evolution of technology has long since eliminated any arbitrary
distinction between a computer and its communication components
or a communications network and its computing    system. Some
organizations have attempted to deal with the phenomenon by
marrying these functions under common leadership. This has
resulted in hyphenated job descriptions such as    Computer-
Communications Systems Staff Officer and names like Information
Technology Group. Unfortunately, these names can mask an
inappropriate or poorly executed realignment of organizational
responsibilities. Ideally, management will recognize there is a
theoretical as well as organizational impact.
    The same is true for the security disciplines. Merely
combining the communications security (COMSEC) and computer
security (COMPUSEC) disciplines under an umbrella of common
management is unacceptable. Even if we address the other, albeit
less technical, aspects of information systems security such as
policy, administration, and personnel security, we still fail to
develop a comprehensive view of this evolving technology. The
reason for this becomes clear when we are reminded it's the
information that is the cornerstone of information systems
security. In this sense, any paradigm which emphasizes the
technology at the expense of information will be lacking.

_____
1. Capt John R. McCumber, Joint Staff, as extracted from
    the proceedings of the 14th National Computer Security
    Conference, October 1991.




                                              ANNEX TO
                                              NSTISSI No. 4011
                    THE NATURE OF INFORMATION
    Defining the nature of information could be a tedious task.
To some it represents the free flowing evolution of knowledge; to
others, it is intelligence to be guarded. Add to this the
innumerable media through which the information is perceived and
we have a confusing array of contradictions. How can we present a
study of information that has universal application?
    It may be best to develop a simple analogy. The chemical
compound H2O means many things to all of us. In its liquid state,
water means life-giving sustenance to a desert-dwelling Bedouin;
to a drowning victim, it is the vehicle of death. The same steam
we use to prepare vegetables could scald an unwary cook. Ice can
impede river-borne commerce on the Mississippi River or make a
drink more palatable. Science, therefore, does not deal with the
perception of the compound, but with its state.

    As the compound H2O can be water, ice or steam, information
has three basic states. At any given moment, information is being
transmitted, stored, or processed. The three states exist
irrespective of the media in which information resides. This
subtle distinction ultimately allows us to encompass all
information systems technology in our model.
    It is possible to look at the three states in microcosm and
say that processing is simply specialized state combinations of
storage and transfer; so, in fact, there are only two possible
states. By delving to this level of abstraction, however, we go
beyond the scope and purpose of the model. The distinction
between the three states is fundamental and necessary to
accurately apply the model. For example, cryptography can be used
to protect information while it's transferred through a computer
network and even while it is stored in magnetic media. However,
the information must be available in plaintext (at least to the
processor) in order for the computer to perform the processing
function. The processing function is a fundamental state that
requires specific security controls.
    When this information is needed to make a decision, the end
user may not be aware of the number of state changes effected.
The primary concern will be certain characteristics of the
information. These characteristics are intrinsic and define the
security-relevant qualities of the information. As such, they
are the next major building block of our information   systems
security model.




                                             ANNEX TO
                                             NSTISSI No. 4011
              CRITICAL INFORMATION CHARACTERISTICS

    Information systems security concerns itself with the
maintenance of three critical characteristics of information:
confidentiality (Pfleeger's "secrecy"), integrity, and
availability [PFL89]. These attributes of information
represent the full spectrum of security concerns in an automated
environment. They are applicable for any organization
irrespective of its philosophical outlook on sharing information.

CONFIDENTIALITY
    Confidentiality is the heart of any security policy for an
information system. A security policy is the set of rules that,
given identified subjects and objects, determines whether a given
subject can gain access to a specific object [DOD85]. In the case
of discretionary access controls, selected users (or groups) are
controlled as to which data they may access. Confidentiality is
then the assurance that access controls are enforced.
Confidentiality is used instead of secrecy to avoid unwarranted
implications that this is solely the domain of governments.
    All organizations have a requirement to protect certain
information. Even owners of a clearinghouse operation or
electronic bulletin need the ability to prevent unwanted access
to supervisory functions within their system. It's also
important to note the definition of data, which must be
protected with confidentiality controls, is broadening throughout
government [OTA87]. Actual information labeling and need-to-know
imperatives are aspects of the system security policy that are
enforced to meet confidentiality objectives. The issue of
military versus civilian security controls is one which need not
impact the development of a comprehensive     representation of
information systems security principles.
INTEGRITY
    Integrity is perhaps the most complex and misunderstood
characteristic of information. We seem to have a better
foundation in the development of confidentiality controls than
those which can help ensure data integrity. Pfleeger defines
integrity as "assets" (which) can only be modified by authorized
parties" [PFL89]. Such a definition unnecessarily confines the
concept to one of access control.




                                             ANNEX TO
                                             NSTISSI No. 4011
    A much broader definition is used here. Data integrity is a
matter of degree (as is the concept of "trust" as applied to
trusted systems) that has to be defined as a quality of the
information and not as who does/does not have access to it.
Integrity is that quality of information that identifies how
closely the data represent reality. How closely does your resume
reflect "you?" Does the credit report accurately reflect the
individual's historical record of financial transactions? The
definition of integrity must include the broad scope of accuracy,
relevancy, and completeness.
    Data integrity calls for a comprehensive set of aids to
promote accuracy and completeness as well as security. This is
not to say that too much information can't be a problem. Data
redundancy and unnecessary records present a variety of
challenges to system implementors and administrators. The users
must define their needs in terms of the information necessary to
perform certain functions. Information systems security
functions help ensure this information is robust and (to the
degree necessary) reflects the reality it is meant to represent.

AVAILABILITY
    Availability is a coequal characteristic with confiden-
tiality and integrity. This vital aspect of security ensures the
information is provided to authorized users when it's requested
or needed. Often it's viewed as a less technical requirement that
is satisfied by redundancies within the information system such
as back-up power, spare data channels, and parallel data bases.
This perception, however, ignores one of the most valuable
aspects of our model that this characteristic provides.
Availability is the check-and-balance constraint on our model.
Because security and utility often conflict, the science of
information systems security is also a study of subtle
compromises.
As well as ensuring system reliability, availability acts as a
metric for determining the extent of information systems security
breaches [DOJ88]. Ultimately, when information      systems
security preventive measures fail, remedial action may be
necessary. This remedial activity normally involves support from
law enforcement or legal departments. In order to pursue formal
action against people who abuse information systems resources,
the ability to prove an adverse impact often hinges




                                             ANNEX TO
                                             NSTISSI No. 4011
on the issue of denying someone the availability of information
resources. Although violations of information confidentiality
and integrity can be potentially more disastrous, denial of
service criteria tend to be easier to quantify and thus create a
tangible foundation for taking action against violators [CHR90].
    The triad of critical information characteristics covers all
aspects of security-relevant activity within the information
system. By building a matrix with the information states
(transmission, storage, processing) positioned along the
horizontal axis and the critical information (confidentiality,
integrity, availability) characteristics aligned down the
vertical, we have the foundation for the model.

                        SECURITY MEASURES
    We've now outlined a matrix that provides us with the
theoretical basis for our model. What it lacks at this stage is a
view of the measures we employ to ensure the critical information
characteristics are maintained while information resides in or
moves between states. It's possible, at this point, to perceive
the chart as a checklist. At a very high level of abstraction,
one could assess the security posture of a system by using this
approach. For example, you may single out systems information
confidentiality during transmission or any intersection area for
scrutiny.
    The two-dimensional matrix also has another less obvious
utility. We can map various security technologies into the nine
boxes. Using our example from above, we note it is       necessary
to protect the confidentiality of the information during its
transmission state. We can then determine which security
technologies help ensure confidentiality during transmission of
the information. In this case, cryptography would be considered a
primary security technology. We can then place various
cryptographic techniques and products within a subset in this
category. Then we repeat the process with other major types of
technology that can be placed within these spaces. The procedure
is repeated for all nine blocks on our grid. Thus we form the
first of three layers which will become the third dimension of our
model--security measures.




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TECHNOLOGY
    The technology layer will be the primary focus of the third
dimension. We will see that it provides the basis for the other
two layers. For our purposes, we can define technology as any
physical device or technique implemented in physical form that is
specifically used to help ensure the critical information
characteristics are maintained through any of the information
states. Technology can be implemented in hardware, firmware, or
software. It could be a biometric device, cryptographic module,
or security-enhanced operating system. When we think of a thing,
which could be used to protect the critical characteristics of
information, we are thinking of technology.
    Usually organizations are built around functional
responsibilities. The advent of computer technology created
the    perception that a group needed to be established to
accommodate the new machines that would process, store, and
transmit much of our vital information. In other words, the
organization was adapted to suit the evolving technology. Is this
wrong? Not necessarily; however, it is possible to create the
impression that technology exists for technology's sake.
Telecommunications and computer systems are simply media for
information. The media need to be adapted to preserve certain
critical characteristics with the adaptation and use of the
information media (technology). Adaptation is a design problem,
but use and application concerns bring us to the next layer.

POLICY AND PRACTICE
    The second layer of the third dimension is that of policy and
practice. It's the recognition of the fact that information
systems security is not just a product that will be available at
some future date. Because of our technology focus, it's easy to
begin to think of security solutions as devices or add-on packages
for existing information systems. We are guilty of waiting for
technology to solve that which is not solely a technological
problem. Having an enforceable (and enforced) policy can aid
immeasurably in protecting information.
    A study has shown 75% of federal agencies don't have a policy
for the protection of information on PC-based information systems
[OTA87]. Why, if it is so effective, is policy such a neglected
security measure? It may be due in part to the evolving social
and moral ethic with regard to our use of




                                              ANNEX TO
                                              NSTISSI No. 4011
information systems. The proliferation of unauthorized software
duplication is just another symptom of this problem. Even though
software companies have policies and licensing caveats on
their products, sanctions and remedies allowed by law are
difficult if not impossible to enforce. No major lawsuit
involving an individual violator has come before our courts, and
it appears many people don't see the harm or loss involved.
Although there are limits established by law, it seems we as
"society" accept a less stringent standard.
    Closely associated with the matter of policy is that of
practice. A practice is a procedure we employ to enhance our
security posture. For example, we may have a policy that states
that passwords must be kept confidential and may only be used by
the uniquely-authenticated user. A practice, which helps ensure
this policy is followed, would be committing the password to
memory rather than writing it somewhere.
    The first two layers of the third dimension represent the
design and application of a security-enhanced information
system. The last building block of our model represents the
understanding necessary to protect information. Although an
integral aspect of the preceding two layers, it must be
considered individually as it is capable of standing alone as a
significant security measure.

EDUCATION, TRAINING, AND AWARENESS
    The final layer of our third dimension is that of education,
training, and awareness. As you will see, were the model laid on
its back like a box, the whole model would rest on this layer.
This phenomenon is intentional. Education, training,
and awareness may be our most prominent security measures, for
only by understanding the threats and vulnerabilities
associated with our proliferating use of automated information
systems can we begin to attempt to deal effectively with other
control measures.
    Technology and policy must rely heavily on education,
training, and awareness from numerous perspectives. Our
upcoming engineers and scientists must understand the principles
of information security if we expect them to consider the
protection of information in the systems they design.
Currently, nearly all university graduates in computer science
have no formal introduction to information security as part of
their education [HIG89].




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                                            NSTISSI No. 4011
    Those who are responsible for promulgating policy and     regu-
latory guidance must place bounds on the dissemination of infor-
mation. They must ensure information resources are     distributed
selectively and securely. The issue is ultimately
one of awareness. Ultimate responsibility for its protection
rests with those individuals and groups that create and use this
information; those who use it to make critical decisions must rely
on its confidentiality, integrity, and availability.
Education, training and awareness promises to be the most
effective security measure in the near term.
    Which information requires protection is often debated in
government circles. One historic problem is the clash of
society's right to know and an individual's right to privacy.
It's important to realize that these are not bipolar concepts.
There is a long continuum that runs between the beliefs that
information is a free flowing exchange of knowledge and that it is
intelligence that must be kept secret. From a governmental or
business perspective, it must be assumed that all information is
intelligence. The question is not should information be
protected, but how do we intend to protect the confiden-tiality,
integrity, and availability of it within legal and moral
constraints?

                            THE MODEL
OVERVIEW
    The completed model is depicted below. There are nine
distinct boxes, each three layers deep. All aspects of
information systems security can be viewed within the framework
of the model. For example, we may cite a cryptographic module as
technology that protects information in its transmission state.
What many information system developers fail to appreciate is
that for every technology control there is a policy (sometimes
referred to as doctrine) that dictates the constraints on the
application of that technology. It may also specify
parameters that delimit the control's use and may even cite
degrees of effectiveness for different applications. Doctrine
(policy) is an integral yet distinct aspect of the technology.
The third layer--education, training, and awareness then
functions as a catalyst for proper application and use of the
technology based on the policy (practice) application.




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                                              NSTISSI No. 4011
    Not every security measure begins with a specific tech- nol-
ogy. A simple policy or practice often goes a long way in the
protection of information assets. This policy or practice is then
effected by communicating it to employees through the education,
training and awareness level alone. This last layer is ultimately
involved in all aspects of the information    systems security
model. The model helps us understand the comprehensive nature of
information security.




                         CHART GOES HERE
            **Call Secretariat for copy of drawing**




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USE OF THE MODEL
    The model has several significant applications. Initially,
the two-dimensional matrix is used to identify information states
and system vulnerabilities. Then, the three layers of security
measures can be employed to minimize these vulnera-bilities based
on a knowledge of the threat to the information asset. Let's take
a brief look at these applications.
    A developer would begin using the model by defining the
various information states within the system. When an
information state is identified, one then works down the vertical
path to address all three critical information characteristics
identifying the vulnerabilities. Once vulnerabilities are noted
in this fashion, it becomes a simple matter of working down
through the three layers of security measures. If a     specific
technology is available, the designer knows that    policy and
practice, as well as education, training, and awareness will be
logical follow-on aspects of that control. If a technology cannot
be identified, then policy/practice must be viewed as the next
likely avenue. If none of the first two layers can satisfactorily
counter the vulnerability then, as a minimum, an awareness of the
weakness becomes important and fulfills the dictates of the model
at the third layer.
    Another important application is realized when the model is
used as an evaluation tool. As in the design and development
application, the evaluator first identifies the different
information states within the system. These states can be
identified separately from a specific technology. A valuable
aspect of the model is the designer need not consider the medium.
    After identifying all the states, an evaluator or auditor can
perform a comprehensive review much the same way the systems
designer used the model during the development phase. For each
vulnerability discovered, the same model is used to determine
appropriate security measures. It is important to note that a
vulnerability may be left unsecured (at an awareness level in the
third layer) if the designer or evaluator determines no threat to
that vulnerability exists. Although no security practitioner
should be satisfied with glaring vulnerabilities, a careful study
of potential threats to the information may disclose that the cost
of the security measure is more than the loss should the
vulnerability be exploited. This is one of the subtle compromises
alluded to earlier.




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                                              NSTISSI No. 4011
    The model can also be used to develop comprehensive
information systems security policy and guidance necessary for
any organization. With an accurate understanding of the relation
of policy to technology and education, training, and awareness,
you can ensure your regulations address the entire spectrum of
information security. It's of particular importance that
corporate and government regulations not be bound by
technology. Use of this model allows management to structure its
policy outside the technology arena.
    The model functions well in determining requirements for
education, training, and awareness. Since this is the last layer,
it plays a vital role in the application of all the security
measures. Even if a designer, evaluator, or user determines to
ignore a vulnerability (perhaps because of a lack of threat), then
the simple acknowledgement of this vulnera-bility resides in the
last layer as "awareness." Ultimately, all technology, policies,
and practices must be translated to the appropriate audience
through education, training, and awareness. This translation is
the vehicle that makes all security measures effective. For a
more complete understanding of the nuances of education,
training, and awareness see [MAC89].
    The 27 individual "cubes" created by the model can be
extracted and examined individually. This key aspect can be
useful in categorizing and analyzing countermeasures. It's also
a tool for defining organizational responsibility for information
security. By considering all 27 such "cubes", the analyst is
assured of a complete perspective of all available security
measures. This model connotes a true "systems"     viewpoint.

                            CONCLUSION
    The information systems security model acknowledges
information, not technology, as the basis for our security
efforts. The actual medium is transparent in the model. This
eliminates unnecessary distinctions between Communications
Security   (COMSEC), Computer Security (COMPUSEC), Technical
Security (TECHSEC), and other technology-defined security
sciences. As a result, we can model the security relevant
processes of information throughout an entire information system-
-automated or not.




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                                              NSTISSI No. 4011
    This model responds to the need for a theoretical foundation
for modeling the information systems security sciences. The pro-
cess begins now by acknowledging the central element in all our
efforts--information. Only when we build on this    foundation
will we accurately address the needs of information systems secu-
rity in the next decade and beyond.

                            REFERENCES
[CHR90]Interview with Agent Jim Christy, Chief, Air Force Office
             of Special Investigations, Computer Crime Division,
             26 March 1990.
[DOD85]Department of Defense Trusted Computer System Evaluation
             Criteria, DoD 5200.28-STD, Department of Defense,
             Washington, DC, December 1985.
[DOJ88]Basic Considerations in Investigating and Proving
             Computer-Related Federal Crimes, U.S. Department of
             Justice, Justice Management Division, Washington, DC,
             November 1988.
[HIG89]Higgins, John C., Information Security as a Topic in
             Undergraduate Education of Computer Scientists,
             Proceedings of the 12th National Computer Security
             Conference, November 1989.
[MAC89]Maconachy, W.V., Computer Security Education, Training,
             and Awareness: Turning a Philosophical Orientation
             into Practical Reality, Proceedings of the 12th
             National Computer Security Conference, November 1989.
[OTA87]U.S. Congress, Office of Technology Assessment, Defending
             Secrets, Sharing Data: New Locks and Keys for
             Electronic Information, OTA-CIT-310, Washington, DC,
             U.S. Government Printing Office, October 1987.
[PFL89]Pfleeger, Charles P., Security in Computing, Prentice-
             Hall, 1989.




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