SIST EN ISO/IEC 27011:2020

SLOVENSKI STANDARD
01-september-2020
Informacijska tehnologija - Varnostne tehnike - Pravila obnašanja pri nadzoru
varnosti informacij, ki temeljijo na ISO/IEC 27002 za telekomunikacijske
organizacije (ISO/IEC 27011:2016)
Information technology - Security techniques - Code of practice for Information security
controls based on ISO/IEC 27002 for telecommunications organizations (ISO/IEC
27011:2016)
Informationstechnik - Sicherheitsverfahren - Leitfaden für
Informationssicherheitsmaßnahmen auf Grundlage von ISO/IEC 27002 für
Telekommunikationsorganisatione (ISO/IEC 27011:2016)
Technologies de l'information - Techniques de sécurité - Code de bonne pratique pour
les contrôles de la sécurité de l'information fondés sur l'ISO/IEC 27002 pour les
organismes de télécommunications (ISO/IEC 27011:2016)
Ta slovenski standard je istoveten z: EN ISO/IEC 27011:2020
ICS:
03.100.70 Sistemi vodenja Management systems
33.030 Telekomunikacijske Telecommunication services.
uporabniške rešitve Applications
35.030 Informacijska varnost IT Security
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD
EN ISO/IEC 27011
NORME EUROPÉENNE
EUROPÄISCHE NORM
May 2020
ICS 03.100.70; 35.030
English version
Information technology - Security techniques - Code of
practice for Information security controls based on
ISO/IEC 27002 for telecommunications organizations
(ISO/IEC 27011:2016)
Technologies de l'information - Techniques de sécurité Informationstechnik - Sicherheitsverfahren - Leitfaden
- Code de bonne pratique pour les contrôles de la für Informationssicherheitsmaßnahmen auf Grundlage
sécurité de l'information fondés sur l'ISO/IEC 27002 von ISO/IEC 27002 für
pour les organismes de télécommunications (ISO/IEC Telekommunikationsorganisatione (ISO/IEC
27011:2016) 27011:2016)
This European Standard was approved by CEN on 3 May 2020.

CEN and CENELEC members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for
giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical
references concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to
any CEN and CENELEC member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by
translation under the responsibility of a CEN and CENELEC member into its own language and notified to the CEN-CENELEC
Management Centre has the same status as the official versions.

CEN and CENELEC members are the national standards bodies and national electrotechnical committees of Austria, Belgium,
Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy,
Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of North Macedonia, Romania, Serbia,
Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom.

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Rue de la Science 23, B-1040 Brussels
© 2020 CEN/CENELEC All rights of exploitation in any form and by any means Ref. No. EN ISO/IEC 27011:2020 E
reserved worldwide for CEN national Members and for
CENELEC Members.
Contents Page
European foreword . 3

European foreword
The text of ISO/IEC 27011:2016 has been prepared by Technical Committee ISO/IEC JTC 1 "Information
technology” of the International Organization for Standardization (ISO) and has been taken over as
the secretariat of which is held by DIN.
This European Standard shall be given the status of a national standard, either by publication of an
identical text or by endorsement, at the latest by November 2020, and conflicting national standards
shall be withdrawn at the latest by November 2020.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of
North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the
United Kingdom.
Endorsement notice
The text of ISO/IEC 27011:2016 has been approved by CEN as EN ISO/IEC 27011:2020 without any
modification.
INTERNATIONAL ISO/IEC
STANDARD 27011
Second edition
2016-12-01
Information technology — Security
techniques — Code of practice for
Information security controls based on
ISO/IEC 27002 for telecommunications
organizations
Technologies de l'information — Techniques de sécurité — Code de
bonne pratique pour les contrôles de la sécurité de l'information fondés
sur l'ISO/IEC 27002 pour les organismes de télécommunications

Reference number
ISO/IEC 27011:2016(E)
©
ISO/IEC 2016
ISO/IEC 27011:2016(E)
©  ISO/IEC 2016
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means,
electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or
ISO's member body in the country of the requester.
ISO copyright office
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Tel. + 41 22 749 01 11
Fax + 41 22 749 09 47
copyright@iso.org
Web www.iso.org
Published in Switzerland
ii © ISO/IEC 2016 – All rights reserved

ISO/IEC 27011:2016(E)
Foreword
ISO (the International Organization for Standardization) and IEC (the International Electrotechnical
Commission) form the specialized system for worldwide standardization. National bodies that are members of
ISO or IEC participate in the development of International Standards through technical committees
established by the respective organization to deal with particular fields of technical activity. ISO and IEC
technical committees collaborate in fields of mutual interest. Other international organizations, governmental
and non-governmental, in liaison with ISO and IEC, also take part in the work. In the field of information
technology, ISO and IEC have established a joint technical committee, ISO/IEC JTC 1.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of the joint technical committee is to prepare International Standards. Draft International
Standards adopted by the joint technical committee are circulated to national bodies for voting. Publication as
an International Standard requires approval by at least 75 % of the national bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO and IEC shall not be held responsible for identifying any or all such patent rights.
This second edition cancels and replaces firs edition of ISO/IEC 27011:2008 which has been technically
revised.
ISO/IEC 27011 was prepared by Joint Technical Committee ISO/IEC JTC 1, Information technology,
Subcommittee SC 27, IT Security techniques, in collaboration with ITU-T. The identical text is published as
Rec. ITU-T X.1051.
© ISO/IEC 2016 – All rights reserved ii-1

CONTENTS
Page
1 Scope . 1
2 Normative references. 1
3 Definitions and abbreviations . 1
3.1 Definitions . 1
3.2 Abbreviations . 2
4 Overview . 2
4.1 Structure of this Recommendation | International Standard . 2
4.2 Information security management systems in telecommunications organizations . 3
5 Information security policies . 5
6 Organization of information security. 5
6.1 Internal organization . 5
6.2 Mobile devices and teleworking . 6
7 Human resource security . 6
7.1 Prior to employment . 6
7.2 During employment . 7
7.3 Termination or change of employment . 7
8 Asset management . 7
8.1 Responsibility for assets . 7
8.2 Information classification . 8
8.3 Media handling . 8
9 Access control . 8
9.1 Business requirement for access control . 8
9.2 User access management . 9
9.3 User responsibilities . 9
9.4 System and application access control . 9
10 Cryptography . 9
11 Physical and environmental security . 9
11.1 Secure areas . 9
11.2 Equipment . 10
12 Operations security . 12
12.1 Operational procedures and responsibilities . 12
12.2 Protection from malware . 13
12.3 Backup . 13
12.4 Logging and monitoring . 13
12.5 Control of operational software . 13
12.6 Technical vulnerability management . 14
12.7 Information systems audit considerations . 14
13 Communications security . 14
13.1 Network security management . 14
13.2 Information transfer. 15
14 System acquisition, development and maintenance . 16
14.1 Security requirements of information systems . 16
14.2 Security in development and support processes . 16
14.3 Test data . 16
15 Supplier relationships . 16
15.1 Information security in supplier relationships . 16
15.2 Supplier service delivery management . 17
16 Information security incident management . 17
16.1 Management of information security incidents and improvements. 17
17 Information security aspects of business continuity management . 19
ITU-T Rec. X.1051 (04/2016) iii

Page
17.1 Information security continuity . 19
17.2 Redundancies . 20
18 Compliance . 20
Annex A – Telecommunications extended control set . 21
Annex B – Additional guidance for network security . 29
B.1 Security measures against network attacks . 29
B.2 Network security measures for network congestion . 30
Bibliography . 31

iv ITU-T Rec. X.1051 (04/2016)

Introduction
This Recommendation | International Standard provides interpretation guidelines for the implementation and management
of information security controls in telecommunications organizations based on ISO/IEC 27002.
Telecommunications organizations provide telecommunications services by facilitating the communications of customers
through their infrastructure. In order to provide telecommunications services, telecommunications organizations need to
interconnect and/or share their services and facilities and/or use the services and facilities of other telecommunications
organizations. Furthermore, the site location, such as radio sites, antenna locations, ground cables and utility provision
(power, water), may be accessed not only by the organization's staff, but also by contractors and providers external to the
organization.
Therefore, the management of information security in telecommunications organizations is complex, potentially:
– depending on external parties;
– having to cover all areas of network infrastructure, services applications and other facilities;
– including a range of telecommunications technologies (e.g., wired, wireless or broadband);
– supporting a wide range of operational scales, service areas and service types.
In addition to the application of security objectives and controls described in ISO/IEC 27002, telecommunications
organizations may need to implement extra controls to ensure confidentiality, integrity, availability and any other security
property of telecommunications in order to manage security risk in an adequate fashion.
1) Confidentiality
Protecting confidentiality of information related to telecommunications from unauthorized disclosure. This
implies non-disclosure of communications in terms of the existence, the content, the source, the destination
and the date and time of communicated information.
It is critical that telecommunications organizations ensure that the non-disclosure of communications being
handled by them is not breached. This includes ensuring that persons engaged by the telecommunications
organization maintain the confidentiality of any information regarding others that may have come to be
known during their work duties.
NOTE – The term "secrecy of communications" is used in some countries in the context of "non-disclosure of
communications".
2) Integrity
Protecting the integrity of telecommunications information includes controlling the installation and use of
telecommunications facilities to ensure the authenticity, accuracy and completeness of information
transmitted, relayed or received by wire, radio or any other method.
3) Availability
Availability of telecommunications information includes ensuring that access to facilities and the medium
used for the provision of communication services is authorized, regardless of whether communications is
provided by wire, radio or any other method. Typically, telecommunications organizations give priority to
essential communications in case of emergencies, managing unavailability of less important
communications in compliance with regulatory requirements.
Audience
The audience of this Recommendation | International Standard consists of telecommunications organizations and those
responsible for information security; together with security vendors, auditors, telecommunications terminal vendors and
application content providers. This Recommendation | International Standard provides a common set of general security
control objectives based on ISO/IEC 27002, telecommunications sector-specific controls and information security
management guidelines allowing for the selection and implementation of such controls.

ITU-T Rec. X.1051 (04/2016) v
ISO/IEC 27011:2016 (E)
INTERNATIONAL STANDARD
ITU-T RECOMMENDATION
Information technology – Security techniques – Code of practice for information security
controls based on ISO/IEC 27002 for telecommunications organizations
1 Scope
The scope of this Recommendation | International Standard is to define guidelines supporting the implementation of
information security controls in telecommunications organizations.
The adoption of this Recommendation | International Standard will allow telecommunications organizations to meet
baseline information security management requirements of confidentiality, integrity, availability and any other relevant
security property.
2 Normative references
The following Recommendations and International Standards contain provisions which, through reference in this text,
constitute provisions of this Recommendation | International Standard. At the time of publication, the editions indicated
were valid. All Recommendations and Standards are subject to revision, and parties to agreements based on this
Recommendation | International Standard are encouraged to investigate the possibility of applying the most recent edition
of the Recommendations and Standards listed below. Members of IEC and ISO maintain registers of currently valid
International Standards. The Telecommunication Standardization Bureau of the ITU maintains a list of currently valid
ITU-T Recommendations.
– ISO/IEC 27000, Information technology – Security techniques – Information security management systems
– Overview and vocabulary.
– ISO/IEC 27002:2013, Information technology – Security techniques – Code of practice for information
security controls.
3 Definitions and abbreviations
3.1 Definitions
For the purposes of this Recommendation | International Standard, the definitions given in ISO/IEC 27000 and the
following apply:
3.1.1 co-location: Installation of telecommunications facilities on the premises of other telecommunications carriers.
3.1.2 communication centre: Building where facilities for providing telecommunications business are sited.
3.1.3 essential communications: Communications whose contents are necessary for the prevention of or relief from
disasters and for the maintenance of public order in adverse conditions.
3.1.4 non-disclosure of communications: Requirement not to disclose the existence, the content, the source, the
destination and the date and time of communicated information.
3.1.5 priority call: Telecommunications made by specific terminals in the event of emergencies, which should be
handled with priority by restricting public calls.
NOTE – The specific terminals may span different services (voice over Internet protocol (VoIP), public switched telephone network
(PSTN) voice, Internet protocol (IP) data traffic, etc.) for wired and wireless networks.
3.1.6 telecommunications applications: Applications such as Voice over IP (VoIP) that are consumed by end-users
and built upon the network based services.
3.1.7 telecommunications business: Business to provide telecommunications services in order to meet the demand
of others.
3.1.8 telecommunications equipment room: A secure location or room within a general building where equipment
for providing telecommunications business are sited.
3.1.9 telecommunications facilities: Machines, equipment, wire and cables, physical buildings or other electrical
facilities for the operation of telecommunications.
ITU-T Rec. X.1051 (04/2016) 1
ISO/IEC 27011:2016 (E)
3.1.10 telecommunications organizations: Business entities who provide telecommunications services in order to
meet the demand of others.
3.1.11 telecommunication records: Information concerning the parties in a communication excluding the contents of
the communication, and the time, and duration of the telecommunication that took place.
3.1.12 telecommunications services: Communications using telecommunications facilities, or any other means of
providing communications either between telecommunications service users or telecommunications service customers.
3.1.13 telecommunications service customer: Person or organization who enters into a contract with
telecommunications organizations to be offered telecommunications services by them.
3.1.14 telecommunications service user: Person or organization who utilizes telecommunications services.
3.1.15 terminal facilities: Telecommunications facilities which are to be connected to one end of telecommunications
circuit facilities and part of which is to be installed on the same premises (including the areas regarded as the same
premises) or in the same building where any other part thereof is also to be installed.
3.1.16 user: Person or organization who utilizes information processing facilities or systems, e.g., employee,
contractor or third party user.
3.2 Abbreviations
For the purposes of this Recommendation | International Standard, the following abbreviations apply:
CIA Confidentiality, Integrity and Availability
CNI Critical National Infrastructure
DDoS Distributed Denial of Service
DNS Domain Name System
DoS Denial of Service
HVAC Heating, Ventilation, and Air Conditioning
IP Internet Protocol
IRC Internet Relay Chat
ISAC Information Sharing and Analysis Centre
ISMS Information Security Management System
NMS Network Management System
OAM&P Operations, Administration, Maintenance and Provisioning
PSTN Public Switched Telephone Network
SIP Session Initiation Protocol
SLA Service Level Agreement
SMS Short Message Service
SOA Statement of Applicability
URL Uniform Resource Locator
VoIP Voice over Internet Protocol
4 Overview
4.1 Structure of this Recommendation | International Standard
This Recommendation | International Standard has been structured in a format similar to ISO/IEC 27002. In cases where
objectives and controls specified in ISO/IEC 27002 are applicable without a need for any additional information, only a
reference is provided to ISO/IEC 27002. A telecommunications sector-specific set of control and implementation
guidance is described in normative Annex A.
In cases where controls need additional guidance specific to telecommunications, the ISO/IEC 27002 control is repeated
without modification, followed by the specific telecommunications guidance related to this control. Telecommunications
sector specific guidance and information is included in the following clauses:
– Organization of information security (clause 6)
2 ITU-T Rec. X.1051 (04/2016)
ISO/IEC 27011:2016 (E)
– Human resources security (clause 7)
– Asset management (clause 8)
– Access control (clause 9)
– Physical and environmental security (clause 11)
– Operations security (clause 12)
– Communications security (clause 13)
– Systems acquisition, development and maintenance (clause 14)
– Supplier relationships (clause 15)
– Information security incident management (clause 16)
– Information security aspects of business continuity management (clause 17)
4.2 Information security management systems in telecommunications organizations
4.2.1 Goal
Information is critical to every organization. In the case of telecommunications, information consists of data transmitted
between any two points in an electronic formation as well as metadata of each transmission, e.g., positioning data of
sender and receiver. Regardless of how the information is transmitted and whether it is cached or stored during
transmission, information should always be appropriately protected.
Telecommunications organizations and their information systems and networks are exposed to security threats from a
wide range of sources, including: wire-tapping; advanced persistent threats; terrorism; espionage; sabotage; vandalism;
information leakage; errors; and force majeure events. These security threats may originate from inside or outside the
telecommunications organization, resulting in damage to the organization.
Once information security is violated, e.g., by wire-tapping the telecommunications lines, the organization may suffer
damage. Therefore, it is essential for an organization to ensure its information security by continual improvement of its
information security management system (ISMS).
Effective information security is achieved by implementing a suitable set of controls based on those described in this
Recommendation | International Standard. These controls need to be established, implemented, monitored, reviewed and
improved in telecommunications facilities, services and applications. These activities will enable an organization to meet
its security objectives and therefore business objectives.
Telecommunications organizations provide facilities to various user types to process, transmit and store information. This
information could be personally identifiable information, or confidential private and business data. In all cases,
information should be handled with the correct level of care and attention, and the appropriate levels of protection
provided to ensure confidentiality, integrity and availability (CIA), with privacy and sensitivity being paramount.
4.2.2 Security considerations in telecommunications
The requirement for a generic security framework in telecommunications has originated from different sources:
a) customers/subscribers needing confidence in the network and the services to be provided, including
availability of services (especially emergency services) in case of major catastrophes;
b) public authorities demanding security by directives, regulation and legislation, in order to ensure
availability of services, fair competition and privacy protection;
c) network operators and service providers themselves needing security to safeguard their operational and
business interests, and to meet their obligations to their customers and the public.
Furthermore, telecommunications organizations should consider the following environmental and operational security
incidents.
a) Telecommunications services are heavily dependent on various interconnected facilities, such as routers,
switches, domain name servers, transmission relay systems and a network management system (NMS).
Therefore, telecommunications security incidents can occur to various equipment/facilities and the
incidents can propagate rapidly through the network into other equipment/facilities.
b) In addition to telecommunications facilities, vulnerabilities in network protocols and topology can result
in serious security incidents. In particular, convergence of wired and wireless networks can impose
significant challenges for developing interoperable protocols.
ITU-T Rec. X.1051 (04/2016) 3
ISO/IEC 27011:2016 (E)
c) A major concern of telecommunications organizations is the possibility of compromised security that
causes network down-time. Such down-time can be extremely costly in terms of customer relations, lost
revenue and recovery costs. Deliberate attacks on the availability of the national telecommunications
infrastructure can be viewed as a national security concern.
d) Telecommunications management networks and systems are susceptible to hacker penetrations. A
common motivation for such penetrations is theft of telecommunications services. Such theft can be
engineered in various ways, such as invoking diagnostic functions, manipulating accounting records,
altering provisioning databases and eavesdropping on subscriber calls.
e) In addition to external penetrations, carriers are concerned about security compromises from internal
sources, such as invalid changes to network management databases and configurations on the part of
unauthorized personnel. Such occurrences may be accidental or deliberate.
f) Telecommunications services can be disrupted by malware such as worms and viruses attacking end
systems or communications infrastructure. DoS/DDoS is a major cause of incidents on communications
and can be caused by various methods to interrupt or block communication signals, or sending data to one
system or network from many hundreds of systems as the same time to overload it (see TEL 13.1.6).
For the purpose of protecting information assets in telecommunications originating from different sources in various
telecommunications environments, security guidelines for telecommunications are indispensable to support the
implementation of information security management in telecommunications organizations.
The security guidelines should be applicable to the following:
a) telecommunications organizations seeking confidence that the information security requirements of their
interested parties (e.g., suppliers, customers, regulators) will be satisfied;
b) telecommunications organizations seeking a business advantage through the implementation of an ISMS;
c) users and suppliers of the information security related products and services for the telecommunications
industry;
d) those internal or external to the telecommunications organization who assess and audit the ISMS for
conformity with the requirements of ISO/IEC 27001;
e) those internal or external to the telecommunications organizations who give advice or training on the ISMS
appropriate to that organization;
f) ensuring compliance with trans-border legal and regulatory requirements, and complying with statutory
requirements in all countries of operation or transit.
4.2.3 Information assets to be protected
In order to establish information security management, it is essential for an organization to clarify and identify all
organizational assets. The clarification of attributes and importance of the assets makes it possible to implement
appropriate controls.
Information assets which telecommunications organizations should protect can be found in clause 8.1.1.
4.2.4 Establishment of information security management
4.2.4.1 How to establish security requirements
It is essential for telecommunications organizations to identify their security requirements. There are three main sources
of security requirements as follows.
a) Those derived from assessing risks to a telecommunications carrier, taking into account its overall business
strategy and objectives. Through risk assessment, threats to assets are identified, vulnerability to and
likelihood of occurrence is evaluated and potential impact is estimated.
b) The legal, statutory, regulatory, and contractual requirements that telecommunications organizations have
to satisfy, trans-border legal and regulatory compliance, and the socio-cultural environment. Examples of
legislative requirements for telecommunications organizations are non-disclosure of communications
(TEL.18.1.6 in Annex A) and ensuring essential communications (TEL.18.1.7 in Annex A). Examples of
socio-cultural requirements are ensuring the integrity of telecommunications that are transmitted, relayed
and received by any means, the availability of wired or wireless telecommunications facilities by
authorized persons and not harming other telecommunications facilities.
c) The particular set of principles, objectives and business requirements for information processing that a
telecommunications carrier has developed to support its operations.
4 ITU-T Rec. X.1051 (04/2016)
ISO/IEC 27011:2016 (E)
4.2.4.2 Assessing security risks
Security requirements are identified by a methodical assessment of security risks. Expenditure on controls needs to be
balanced against the business harm likely to result from security failures. The results of the risk assessment will help to
guide and determine the appropriate management action and priorities for managing information security risks, and for
implementing controls selected to protect against these risks.
Risk assessment should be repeated periodically and at least annually, to address any changes that might influence the
risk assessment results.
4.2.4.3 Selecting controls
Once security requirements and risks have been identified and decisions for the treatment of risks have been made,
appropriate controls should be selected and implemented to ensure risks are reduced to an acceptable level.
This Recommendation | International Standard provides additional guidance and telecommunications-specific controls,
in addition to general information security management, taking account of telecommunications-specific requirements.
Therefore, telecommunications organizations are recommended to select controls from this Recommendation |
International Standard and implement them. In addition, new controls can be designed to meet specific needs as
appropriate.
The selection of security controls is dependent upon organizational decisions based on the criteria for risk acceptance,
risk treatment options and the general risk management approach applied to telecommunications organizations;
additionally, the selection should be subject to all relevant national and international legislation and regulations.
5 Information security policies
The control objective and the contents from ISO/IEC 27002 clause 5 apply.
NOTE – It might be necessary to take account of telecommunications-specific legislation and regulatory requirements and
associated requirements concerning how these are both met and evidenced.
6 Organization of information security
6.1 Internal organization
Objective: To establish a management framework to initiate and control the implementation and operation of information
security within the organization.
6.1.1 Information security roles and responsibilities
Control
All information security responsibilities should be defined and allocated.
Implementation guidance
The implementation guidance from ISO/IEC 27002 6.1.1 applies.
Telecommunications-specific implementation guidance
There should be an appointment of an executive manager who is responsible for all risks to telecommunication
infrastructure and is accountable for their management.
Telecommunications organizations should appoint telecommunications engineers and other staff, who have the right
credentials or appropriate knowledge and skills, to be in charge of the supervision of matters related to the installation,
maintenance and operation of telecommunications facilities for the telecommunications business. The relevant telecoms
engineers and other staff should be notified of and formally agree to their assigned roles and responsibilities.
Where cryptography is used, there should be specific crypto-custodian roles and personnel in these positions should be
properly trained in the management of cryptographic material and the use and protection of cryptographic systems.
Other information
The other information from ISO/IEC 27002 6.1.1 applies.
ITU-T Rec. X.1051 (04/2016) 5
ISO/IEC 27011:2016 (E)
6.1.2 Segregation of duties
Control and the contents from ISO/IEC 27002 6.1.2 apply.
6.1.3 Contact with authorities
Control
Appropriate contacts with relevant authorities should be maintained.
Implementation guidance
The implementation guidance from ISO/IEC 27002 6.1.3 applies.
Telecommunications-specific implementation guidance
When telecommunications organizations receive enquiries from law-enforcement agencies or investigative organizations
regarding information relating to telecommunications service users, these telecommunications organizations need to
confirm that the enquiries have gone through legitimate processes and procedures according to national laws and
regulations before any information is disclosed.
The applications and infrastructure of telecommunications organizations can be considered part of critical infrastructure
and may be essential for the functioning of the community, society and economy as a whole. Operators of such systems
should therefore maintain contact with all of the relevant authorities. Telecommunications organizations should therefore
maintain contact with all of the relevant authorities.
Other information
The other information from ISO/IEC 27002 6.1.3 applies.
6.1.4 Contact with special interest groups
Control and the contents from ISO/IEC 27002 6.1.4 apply.
6.1.5 Information security in project management
Control and the contents from of ISO/IEC 27002 6.1.5 apply.
6.2 Mobile devices and teleworking
The control objectives and the contents from ISO/IEC 27002 6.2 apply.
7 Human resource security
7.1 Prior to employment
Objective: To ensure that employees and contractors understand their responsibilities and are suitable for the roles for
which they are considered.
7.1.1 Screening
Control
Background verification checks on all candidates for employment should be carried out in accordance with relevant laws,
regulations and ethics, and should be proportional to the business requirements, the classification of the information to be
accessed and the perceived risks.
Implementation guidance
The implementation guidance from ISO/IEC 27002 7.1.1 applies.
Telecommunications-specific implementation guidance
Telecommunications organizations should consider detailed checks on candidates for job positions that give employees
access to sensitive information. This should also apply to positions giving employees access to telecommunications
equipment or to communications information as this could provide unrestricted access to data which can become sensitive
as a result of aggregation.
6 ITU-T Rec. X.1051 (04/2016)
ISO/IEC 27011:2016 (E)
NOTE – Any person who is involved with critical national infrastructure (CNI) aspects of communications systems should be
subjected to formal screening and criminal records checks before being given access.
7.1.2 Terms and conditions of employment
Control
The contractual agreements with employees and contractors should state their and the organization's responsibilities for
information security.
Implementation guidance
The implementation guidance from ISO/IEC 27002 7.1.2 applies.
Telecommunications-specific implementation guidance
The legal rights and responsibilities regarding non-disclosure of communications and essential communications, which
telecommunications organizations should take into account, are included in the laws and regulations.
Telecommunications organizations should clarify and state the responsibilities for maintaining the communications
service provided by telecommunications organizations in addition to the protection and non-disclosure of personally
identifiable and other confidential information in the terms and conditions of employment.
Telecommunications organiza
...