Lecture CCNA security partner - Chapter 1: Network security concepts and policies

This chapter discusses how to develop a comprehensive network security policy to counter threats against information security. It also teaches you about possible threats and how to describe and implement the process of developing a security policy. It covers the identification of common vulnerabilities and threats, mitigation strategies, and the implementation of a security architecture using a lifecycle approach.

Network Security Concepts and Policies © 2012 Cisco and/or its affiliates All rights reserved Purpose of Security • To protect assets! – Historically done through physical security and closed networks © 2012 Cisco and/or its affiliates All rights reserved The Network Today • With the advent of personal computers, LANs, and the wide-open world of the Internet, the networks of today are more open © 2012 Cisco and/or its affiliates All rights reserved Basic Security Requirements • To provide adequate protection of network resources, the procedures and technologies that you deploy need to guarantee three things : – Confidentiality – Integrity – Availability of systems and data © 2012 Cisco and/or its affiliates All rights reserved Data, Vulnerabilities, and Countermeasures • An asset is anything of value to an organization • A vulnerability is a weakness in a system or its design that could be exploited by a threat • A threat is a potential danger to information or systems • A risk is the likelihood that a particular vulnerability will be exploited • An exploit is an attack performed against a vulnerability • A countermeasure (safeguard) is the protection that mitigates the potential risk © 2012 Cisco and/or its affiliates All rights reserved Need for Network Security • Business goals and risk analysis drive the need for network security • Dealing with Risk : – Reduce – Limitation/avoidance – Assurance – Detection – Recoverry © 2012 Cisco and/or its affiliates All rights reserved Need for Network Security © 2012 Cisco and/or its affiliates All rights reserved Adversaries, Methodologies, and Classes of Attack • Adversaries : To defend against attacks on information and information systems, organizations must begin to define the threat by identifying potential adversaries These adversaries can include the following: • Nations or states • Terrorists • Criminals • Hackers • Corporate competitors • Disgruntled employees • Government agencies, such as the National Security Agency (NSA) and the Federal Bureau of Investigations (FBI) © 2012 Cisco and/or its affiliates All rights reserved Adversaries, Methodologies, and Classes of Attack • Methodologies : – Step Perform footprint analysis (reconnaissance) – Step Enumerate applications and operating systems – Step Manipulate users to gain access – Step Escalate privileges – Step Gather additional passwords and secrets – Step Install back doors – Step Leverage the compromised system © 2012 Cisco and/or its affiliates All rights reserved Adversaries, Methodologies, and Classes of Attack Threats Classification • Enumeration and fingerprinting • Spoofing and impersonation • Man-in-the-middle • Overt and covert channels • Blended threats and malware • Exploitation of privilege and trust • Confidentiality • Password attacks • Availability attacks • Denial of service (DoS) • Botnet • Physical security attacks © 2012 Cisco and/or its affiliates All rights reserved 10 Sequence Prediction Sequence Number Prediction © 2012 Cisco and/or its affiliates All rights reserved 12 Trust Exploitation Trust Exploitation © 2012 Cisco and/or its affiliates All rights reserved 13 Confidentiality and Integrity Attacks Breach of Confidentiality © 2012 Cisco and/or its affiliates All rights reserved 14 Man-in-the-Middle Attacks IP Source Routing Attack © 2012 Cisco and/or its affiliates All rights reserved 15 Overt and Covert Channels Overt Channel © 2012 Cisco and/or its affiliates All rights reserved 16 Principles of Secure Network Design • Defense in depth • Compartmentalization • Least privilege • Weakest link • Separation and rotation of duties • Hierarchically trusted components and protection • Mediated access • Accountability and traceability © 2012 Cisco and/or its affiliates All rights reserved 17 Evaluating and Managing the Risk © 2012 Cisco and/or its affiliates All rights reserved 18 Risk Analysis and Management • Every process of security should first address the following questions: • Which are the threats the system is facing? • Which are the probable threats and what would be their consequence, if exploited? • The threat-identification process provides an organization with a list of threats to which a system is subject in a particular environment © 2012 Cisco and/or its affiliates All rights reserved 19 Risk Analysis Quantitative Qualitative â 2012 Cisco and/or its affiliates All rights reserved 20 Building Blocks of Risk Analysis List of Assets and Their Value • Assets and their value • Vulnerabilities • Threats, their impact, and rate or probability of occurrence © 2012 Cisco and/or its affiliates All rights reserved 21 A Lifecycle Approach to Risk Management © 2012 Cisco and/or its affiliates All rights reserved 22 Security Policies The three reasons for having a security policy are as follows: • To inform users, staff, and managers • To specify mechanisms for security • To provide a baseline A properly defined security policy does the following: • Protects people and information • Sets the rules for expected behavior • Authorizes staff to monitor, probe, and investigate Defines the consequences of violations â 2012 Cisco and/or its affiliates All rights reserved 23 Security Policy Components Components of a Comprehensive Security Policy © 2012 Cisco and/or its affiliates All rights reserved 24 Secure Network Lifecycle Management Organization-wide Integration of IT Governance, Risk Management, Compliance © 2012 Cisco and/or its affiliates All rights reserved 25 © 2012 Cisco and/or its affiliates All rights reserved 26 ... Cisco and/ or its affiliates All rights reserved Adversaries, Methodologies, and Classes of Attack Threats Classification • Enumeration and fingerprinting • Spoofing and impersonation • Man-in-the-middle... the potential risk © 2012 Cisco and/ or its affiliates All rights reserved Need for Network Security • Business goals and risk analysis drive the need for network security • Dealing with Risk :...Purpose of Security • To protect assets! – Historically done through physical security and closed networks © 2012 Cisco and/ or its affiliates All rights reserved The Network Today • With