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C8- Securing Information Systems. Definitions . Security: the policies, procedures and technical measures used to prevent unauthorized access, alteration, threat or physical damage to information systems
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Definitions • Security: the policies, procedures and technical measures used to prevent unauthorized access, alteration, threat or physical damage to information systems • Controls: methods to ensure the safety of assets, reliability of records and adherence to standards
Contemporary Security Challenges and Vulnerabilities The architecture of a Web-based application typically includes a Web client, a server, and corporate information systems linked to databases. Each of these components presents security challenges and vulnerabilities. Floods, fires, power failures, and other electrical problems can cause disruptions at any point in the network. Figure 8-1 8-5
System Vulnerability and Abuse Internet vulnerabilities • Vulnerable to outside attacks • Abuses can have widespread impact • E-mail increases system vulnerability Wireless security challenges • The service set identifiers (SSID)identifying the access points broadcast multiple times 8-6
Malicious Software Programs (Malware) • Computer viruses: • Rogue software programs that attach to other programs in order to be executed, usually without user knowledge or permission • Deliver a “payload” • Can spread by email attachments • Worms: • Programs that copy themselves from one computer to another over networks • Can destroy data, programs, and halt operation of computer networks • Trojan Horse: • A software program that appears to be benign, but then does something unexpected • Often “transports” a virus into a computer system System Vulnerability and Abuse 8-8
Hackers and Cybervandalism • Hackers: individuals who attempt to gain unauthorized access to a computer system • Cracker: a hacker with criminal intent • Cybervandalism: intentional disruption, defacement, or destruction of a Web site or system System Vulnerability and Abuse 8-11
Spoofing and Sniffing • Spoofing • masquerading as someone else, or redirecting a Web link to an unintended address • Sniffing • an eavesdropping program that monitors information travelling over a network System Vulnerability and Abuse 8-12
Denial of Service (DoS) Attacks • Hackers flood a server with false communications in order to crash the system System Vulnerability and Abuse 8-13
Computer Crime ... • Identity theft • A crime in which the imposter obtains key pieces of personal information • Phishing • Setting up fake Web sites or sending email messages that look legitimate, and using them to ask for confidential data • Cyberterrorism and Cyberwarfare • Exploitation of systems by terrorists • Internal Threats: Employees • Software vulnerability violation of criminal law that involves a knowledge of technology for perpetration, investigation, or prosecution 8-16
Business Value of Security and Control • Protect own information assets and customers, employees, and business partner • legal liability • litigation for data exposure or theft • A sound security and control framework= high return on investment 8-18
Establishing a Framework for Security and Control • Risk Assessment • Determine level of risk to the firm in the case of improper controls • Security policy • Chief Security Officer (CSO) • Acceptable Use Policy (AUP) • Authorization Policies • Authorization Management systems • Ensuring business continuity • Fault-tolerant computer systems • High-availability computing • Recovery-oriented computing • Disaster recovery planning and business continuity planning • Security outsourcing • The role of auditing 8-20
Technologies And Tools for Security and Control • Access controls • Consist of all the policies and procedures a company uses to prevent improper access to systems by unauthorized insiders and outsiders • Authentication • ability to know that a person is who she or he claims to be • Passwords, tokens, biometric authentication
Firewalls • Firewalls: Hardware and software controlling flow of incoming and outgoing network traffic • Packet Filtering examines selected fields in the headers of data packets flowing back and forth from network and the Internet • Stateful inspection provides additional security by determining whether packets are part of an ongoing dialogue between a sender and receiver Technologies And Tools For Security And Control
Intrusion Detection Systems, and Antivirus • Intrusion Detection Systems • Full-time monitoring tools placed at the most vulnerable points of the corporate networks to detect and deter intruders • Antivirus and Antispyware • Checks computer systems for viruses Technologies And Tools For Security And Control 8-27
Encryption • Encryption • Coding and scrambling of messages to prevent unauthorized access to, or understanding of, the data being transmitted • Public key encryption: • Uses two different keys, one private and one public. The keys are mathematically related so that data encrypted with one key can be decrypted using only the other key • Public Key Infrastructure (PKI): • Use of public key cryptography working with a certificate authority Technologies And Tools For Security And Control
Public Key Encryption A public key encryption system can be viewed as a series of public and private keys that lock data when they are transmitted and unlock the data when they are received. The sender locates the recipient’s public key in a directory and uses it to encrypt a message. The message is sent in encrypted form over the Internet or a private network. When the encrypted message arrives, the recipient uses his or her private key to decrypt the data and read the message. Technologies And Tools For Security And Control 8-31
Solution Guidelines • Security and control must become a more visible and explicit priority and area of information systems investment • Support and commitment from top management is required to show that security is indeed a corporate priority and vital to all aspects of the business • Security and control should be the responsibility of everyone in the organization Management Opportunities, Challenges, And Solutions
Learning Objectives • Analyze why information systems need special protection from destruction, error, and abuse. • Assess the business value of security and control. • Design an organizational framework for security and control. • Evaluate the most important tools and technologies for safeguarding information resources. 8-20