1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS ISO/IEC 27033-3:2010Information technology Security techniques Network securityPart 3: Reference networking scenarios Threats, design techniques and control issuesBS ISO/IEC 2
2、7033-3:2010 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of ISO/IEC27033-3:2010.The UK participation in its preparation was entrusted to TechnicalCommittee IST/33, IT - Security techniques.A list of organizations represented on this committee can beobtained on requ
3、est to its secretary.This publication does not purport to include all the necessaryprovisions of a contract. Users are responsible for its correctapplication. BSI 2011ISBN 978 0 580 65100 7ICS 35.040Compliance with a British Standard cannot confer immunity fromlegal obligations.This British Standard
4、 was published under the authority of theStandards Policy and Strategy Committee on 28 February 2011.Amendments issued since publicationDate Text affectedBS ISO/IEC 27033-3:2010Reference numberISO/IEC 27033-3:2010(E)ISO/IEC 2010INTERNATIONAL STANDARD ISO/IEC27033-3First edition2010-12-15Information
5、technology Security techniques Network security Part 3: Reference networking scenarios Threats, design techniques and control issues Technologies de linformation Techniques de scurit Scurit de rseau Partie 3: Scnarios de rseautage de rfrence Menaces, techniques conceptuelles et questions de contrle
6、BS ISO/IEC 27033-3:2010ISO/IEC 27033-3:2010(E) PDF disclaimer This PDF file may contain embedded typefaces. In accordance with Adobes licensing policy, this file may be printed or viewed but shall not be edited unless the typefaces which are embedded are licensed to and installed on the computer per
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9、 Secretariat at the address given below. COPYRIGHT PROTECTED DOCUMENT ISO/IEC 2010 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 permissio
10、n in writing from either ISO at the address below or ISOs member body in the country of the requester. ISO copyright office Case postale 56 CH-1211 Geneva 20 Tel. + 41 22 749 01 11 Fax + 41 22 749 09 47 E-mail copyrightiso.org Web www.iso.org Published in Switzerland ii ISO/IEC 2010 All rights reser
11、vedBS ISO/IEC 27033-3:2010ISO/IEC 27033-3:2010(E) ISO/IEC 2010 All rights reserved iiiContents Page Foreword iv 1 Scope1 2 Normative references1 3 Terms and definitions .1 4 Abbreviated terms.2 5 Structure.3 6 Overview.4 7 Internet access services for employees .6 7.1 Background6 7.2 Security threat
12、s .7 7.3 Security design techniques and controls.7 8 Business to business services 9 8.1 Background9 8.2 Security threats .9 8.3 Security design techniques and controls.10 9 Business to customer services .11 9.1 Background11 9.2 Security threats .11 9.3 Security design techniques and controls.12 10
13、Enhanced collaboration services 13 10.1 Background13 10.2 Security threats .14 10.3 Security design techniques and controls.14 11 Network segmentation15 11.1 Background15 11.2 Security threats .15 11.3 Security design techniques and controls.15 12 Networking support for home and small business offic
14、es.16 12.1 Background16 12.2 Security threats .16 12.3 Security design techniques and controls.17 13 Mobile communication18 13.1 Background18 13.2 Security threats .18 13.3 Security design techniques and controls.19 14 Networking support for travelling users.20 14.1 Background20 14.2 Security threat
15、s .20 14.3 Security design techniques and controls.20 15 Outsourced services.21 15.1 Background21 15.2 Security threats .21 15.3 Security design techniques and controls.22 Annex A (informative) An Example Internet Use Policy23 Annex B (informative) Catalogue of Threats27 BS ISO/IEC 27033-3:2010ISO/I
16、EC 27033-3:2010(E) iv ISO/IEC 2010 All rights reservedForeword 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
17、 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-gov
18、ernmental, 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
19、 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 v
20、ote. 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. ISO/IEC 27033-3 was prepared by Joint Technical Committee ISO/IEC JTC 1, Information tec
21、hnology, Subcommittee SC 27, IT Security techniques. ISO/IEC 27033 consists of the following parts, under the general title Information technology Security techniques Network security: Part 1: Overview and concepts Part 2: Guidelines for the design and implementation of network security Part 3: Refe
22、rence network scenarios Threats, design techniques and control issues The following parts are under preparation: Part 4: Securing communications between networks using security gateways Threats, design techniques and control issues Part 5: Securing virtual private networks Threats, design techniques
23、 and control issues There may be future parts to cover topics such as local area networks, wide area networks, wireless and radio networks, broadband networks, voice networks, Internet Protocol (IP) convergence (data, voice, video) networks, web host architectures, Internet email architectures (incl
24、uding outgoing online access to the Internet, and incoming access from the Internet), and routed access to third party organizations. BS ISO/IEC 27033-3:2010INTERNATIONAL STANDARD ISO/IEC 27033-3:2010(E) ISO/IEC 2010 All rights reserved 1Information technology Security techniques Network security Pa
25、rt 3: Reference networking scenarios Threats, design techniques and control issues 1 Scope This part of ISO/IEC 27033 describes the threats, design techniques and control issues associated with reference network scenarios. For each scenario, it provides detailed guidance on the security threats and
26、the security design techniques and controls required to mitigate the associated risks. Where relevant, it includes references to ISO/IEC 27033-4 to ISO/IEC 27033-6 to avoid duplicating the content of those documents. The information in this part of ISO/IEC 27033 is for use when reviewing technical s
27、ecurity architecture/design options and when selecting and documenting the preferred technical security architecture/design and related security controls, in accordance with ISO/IEC 27033-2. The particular information selected (together with information selected from ISO/IEC 27033-4 to ISO/IEC 27033
28、-6) will depend on the characteristics of the network environment under review, i.e. the particular network scenario(s) and technology topic(s) concerned. Overall, this part of ISO/IEC 27033 will aid considerably the comprehensive definition and implementation of security for any organizations netwo
29、rk environment. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. ISO/IEC 27
30、000, Information technology Security techniques Information security management systems Overview and vocabulary ISO/IEC 27033-1, Information technology Security techniques Network security Part 1: Overview and concepts 3 Terms and definitions For the purposes of this document, the terms and definiti
31、ons given in ISO/IEC 27000, ISO/IEC 27033-1 and the following apply. 3.1 malware malicious software category of software that is designed with a malicious intent, containing features or capabilities that could potentially cause harm directly or indirectly to the user and/or the users computer system
32、 NOTE See ISO/IEC 27032. BS ISO/IEC 27033-3:2010ISO/IEC 27033-3:2010(E) 2 ISO/IEC 2010 All rights reserved3.2 opacity protection of information that might be derived by observing network activities, such as deriving addresses of end-points in a voice-over-Internet-Protocol call NOTE Opacity recogniz
33、es the need to protect actions in addition to information. 3.3 outsourcing acquisition of services by an acquirer to perform activities required to support the acquirers business functions 3.4 social engineering act of manipulating people into performing actions or divulging confidential information
34、 4 Abbreviated terms AAA Authentication, Authorization and Accounting DHCP Dynamic Host Configuration Protocol DNS Domain Name Service DNSSEC DNS SECurity extensions DoS Denial of Service FTP File Transfer Protocol IDS Intrusion Detection System IP Internet Protocol IPsec IP Security Protocol OAM a
35、clause for each reference scenario (clause 7-15), which describes o threats for the reference scenario, o a presentation of the security controls and techniques based on the approach in clause 6. The scenarios in the document are ordered per the following framework where the objective is to evaluate
36、 a given scenario as a function of the: type of user access, whether the user is inside an enterprise, or the user is an employee who is accessing enterprise resources from outside, or the user is a consumer, vendor or business partner, and, type of information resources accessed, open, restricted o
37、r outsourced resources. Thus, the framework helps present a consistent structure, and makes addition of new scenarios manageable, as well as justifies the need for the various scenarios presented in this part of ISO/IEC 27033. Table 1 Framework for Ordering Network Scenarios Users Inside Employees f
38、rom outside Outside Open - Internet access services for employees - Business to business services - Business to customer services Restricted - Enhanced collaboration services - Business to business services - Network segmentation - Networking support for home and small business offices - Mobile comm
39、unication - Networking support for travelling users - Enhanced collaboration services - Business to business services - Business to customer services Accessed information resources Outsourced - Outsourced services - Outsourced services BS ISO/IEC 27033-3:2010ISO/IEC 27033-3:2010(E) 4 ISO/IEC 2010 Al
40、l rights reservedThus, the order in which the scenarios are listed in this part of ISO/IEC 27033 is as follows: Internet access services for employees (clause 7); Business to business services (clause 8); Business to customer services (clause 9); Enhanced collaboration services (clause 10); Network
41、segmentation (clause 11); Networking support for home and small business offices (clause 12); Mobile communication (clause 13); Networking support for travelling users (clause 14); Outsourced services (clause 15). 6 Overview The guidance presented in this part of ISO/IEC 27033 for each of the identi
42、fied reference network scenarios is based on the following approach. Review the background information and scope of the scenario. Describe the threats relevant to the scenario. Perform risk analysis on discovered vulnerabilities. Analyse the business impact of addressing the vulnerabilities. Determi
43、ne the implementation recommendations for securing the network. In order to address the security of any network, an approach that is systematic and provides an end-to-end evaluation is desirable. The complexity of such an analysis is a function of the nature and size of the network in scope. However
44、, a consistent methodology is important to managing security, especially due to the evolving nature of technology. The first consideration in a security assessment is the determination of assets that require protection. These can be largely categorized into infrastructure, services or application as
45、sets. However, an enterprise can chose to define their own categories, but the distinction is important because the exposure to threats and attacks is unique to each asset category or type. For instance, if a router is categorized an infrastructure asset, and Voice over IP as an end-user service, th
46、en a Denial of Service (DoS) attack requires a different consideration in each case . Specifically, the router requires protection against a flood of bogus packets on the routers physical port that can prevent or impede the transmission of legitimate traffic. Similarly, the VoIP service requires pro
47、tection of the subscribers account/service information from deletion or corruption such that a legitimate user is not prevented from accessing the service. Network security also entails protection of the various activities supported on the network, such as management activities; control/signaling me
48、ssages; and end-user data (resident and in-transit). For example, a management GUI can be subject to disclosure as a result of unauthorized access (easy to guess administrator ID and password). The management traffic itself is subject to corruption due to forged OA if Internet access is also allowed
49、 in (limited) form for private purposes, which services are allowed to be used; if enhanced collaboration services are allowed; if employees are allowed to participate in chat channels, forums etc. BS ISO/IEC 27033-3:2010ISO/IEC 27033-3:2010(E) ISO/IEC 2010 All rights reserved 7Even though often a written policy acts as a significant deterrent to unacceptable Internet usage, the organization is still subject to substantial infor
