2-OSI SECURITY ARCHITECTURE F1.pptxfdddss
- 2. OSI SECURITY ARCHITECTURE • X.800 is a standard developed by the International Telecommunication Union (ITU) defined Security Architecture for OSI. • OSI Security Architecture – provides a framework for security services in open systems. – defines security to systems and also for the data being transferred between them. – Open systems refer to computer systems that interact with other systems over a network, often using standardized communication protocols.
- 3. OSI SECURITY ARCHITECTURE • The OSI security architecture is useful to managers as a way of organizing the task of providing security. • Furthermore, because this architecture was developed as an international standard, computer and communications vendors have developed security features for their products and services that relate to this structured definition of services and mechanisms.
- 5. THE OSI SECURITY ARCHITECTURE • Security attack: Any action that compromises the security of information owned by an organization. • Security service: A processing or communication service that enhances the security of the data processing systems and the information transfers of an organization. The services are intended to counter security attacks and are implemented by security mechanisms. • Security mechanism: A process (or a device incorporating such a process) that is designed to detect, prevent, or recover from a security attack.
- 6. SECURITY ATTACK • Unauthorized attempt to access, manipulate, damage, disrupt, or disable computer systems, networks, or data. • Attacks are carried out by individuals or groups, often referred to as attackers.
- 8. SECURITY ATTACKS • Broadly classified into two types – passive attacks – active attacks
- 10. Passive Attacks • Passive attacks are in the nature of eavesdropping on, or monitoring of, transmissions. • The goal of the opponent is to obtain information that is being transmitted. • Two types of passive attacks are the – release of message contents – traffic analysis.
- 11. Release of message contents- obtain information that is being transmitted.
- 12. Traffic analysis- monitoring the transmissions. • The opponent could determine the – location of communicating hosts – identity the communicating hosts – observe the frequency of messages being exchanged. – length of messages being exchanged.
- 13. Traffic analysis
- 14. Active Attacks Active attacks involve –some modification of the data stream –or the creation of a false stream –can be subdivided into four categories: • masquerade • replay • modification of messages • denial of service.
- 15. Masquerade • Masquerade takes place when one entity pretends to be a different entity.
- 16. Masquerade
- 17. Replay • Replay involves the passive capture of a data unit and its subsequent retransmission to produce an unauthorized effect.
- 18. Replay
- 19. Modification of messages • Modification of messages simply means that some portion of a legitimate message is altered, or that messages are delayed or reordered, to produce an unauthorized effect
- 21. Denial of service • Denial of service prevents or inhibits the normal use or management of communications facilities. • This attack may have a specific target. • for example, an entity may suppress all messages directed to a particular destination.
- 23. SECURITY SERVICES • X.800 defines a security service as a service that is provided by a protocol layer of communicating open systems and that ensures adequate security of the systems or of data transfers. • Security services implement security policies and are implemented by security mechanisms.
- 26. AUTHENCATION
- 36. Non Repudiation
- 37. SECURITY MECHANISMS • The mechanisms are divided into two types: – those that are implemented in a specific protocol layer, such as TCP or an application-layer protocol – those that are not specific to any particular protocol layer or security service. Two Types • SPECIFIC SECURITY MECHANISMS (implemented in a specific protocol layer) • PERVASIVE SECURITY MECHANISMS (not specific to any particular protocol layer)
- 38. SPECIFIC SECURITY MECHANISMS • May be incorporated into the appropriate protocol layer in order to provide some of the OSI security services. The mechanisms are:
- 39. Encipherment • The use of mathematical algorithms to transform data into a form that is not readily intelligible. • The transformation and subsequent recovery of the data depend on an algorithm and zero or more encryption keys.
- 41. Digital Signature • Data appended to, or a cryptographic transformation of, a data unit that allows a recipient of the data unit to prove the source and integrity of the data unit and protect against forgery.
- 43. Access Control • A variety of mechanisms that enforce access rights to resources.
- 44. Data Integrity • A variety of mechanisms used to assure the integrity of a data unit or stream of data units.
- 45. Traffic Padding • The insertion of bits into gaps in a data stream to frustrate traffic analysis attempts.
- 46. Routing Control • Enables selection of particular physically secure routes for certain data and allows routing changes, especially when a breach of security is suspected.
- 47. Notarization • The use of a trusted third party to assure certain properties of a data exchange.
- 48. Authentication Exchange • A mechanism intended to ensure the identity of an entity by means of information exchange.
- 49. PERVASIVE SECURITY MECHANISMS • Mechanisms that are not specific to any particular OSI security service or protocol layer. The mechanisms are:
- 50. Trusted Functionality • Trusted Functionality refers to specific functions within a system that perform their intended actions securely. • Trusted Functionalities operate under strict security protocols, ensuring they cannot be easily tampered with by malicious entities. • Trusted functionalities include: – Key Management – Authentication and Authorization – Data Integrity and Confidentiality
- 51. Security Label • A security label is a tag of metadata attached to an object, such as a file, database record, or communication message, indicating the level of security associated with that object. • Security labels are used to enforce access control policies, ensuring that only authorized users or systems can access or modify the labeled object according to its security classification.
- 52. Security Label
- 53. Event Detection • Detection of security-relevant events.
- 54. Security Audit Trial • Data collected and potentially used to facilitate a security audit, which is an independent review and examination of system records and activities.
- 56. SECURITY RECOVERY • Deals with requests from mechanisms, such as event handling and management functions, and takes recovery actions.