Classified along three independent dimensions:
The type of operations used for transforming plaintext to ciphertext
The number of keys used
symmetric (single key)
asymmetric (two-keys, or public-key encryption)
The way in which the plaintext is processed
After studying this chapter, you should be able to: Identify and explain controls designed to protect the confidentiality of sensitive corporate information; identify and explain controls designed to protect the privacy of personal information collected from customers, employees, suppliers, or business partners; explain how the two basic types of encryption systems work.
The Security Problem Program Threats System and Network Threats Cryptography as a Security Tool User Authentication Implementing Security Defenses Firewalling to Protect Systems and Networks Computer-Security Classifications An Example: Windows XP
To discuss security threats and attacks To explain the fundamentals of encryption, authentication, and hashing To examine the uses of cryptography in computing To describe the various countermeasures to security attacks
Security Attack: Any action that compromises the security of information.
Security Mechanism: A mechanism that is designed to detect, prevent, or recover from a security attack.
Security Service: A service that enhances the security of data processing systems and information transfers. A security service makes use of one or more security mechanisms.
key concerns are confidentiality and timeliness
to provide confidentiality must encrypt identification and session key info
which requires the use of previously shared private or public keys
need timeliness to prevent replay attacks
provided by using sequence numbers or timestamps or challenge/response
Effective means of protection a local system or network of systems from network-based security threats while affording access to the outside world via WAN`s or the Internet.Effective means of protection a local system or network of systems from network-based security threats while affording access to the outside world via WAN`s or the Internet
Any message written over a fixed set of symbols can be represented as a binary string (a sequence of 0's and 1's)
Binary digits 0 and 1 are called bits
To reduce computation overhead, encryption algorithms should only use operations that are easy to implement
For a binary string X:
The length of X, denoted by |X|, is the number of bits in X
If |X| = l, X is an l-bit binary string
Let a be a binary bit and k a non-negative integer. Denote by ak a binary string consisting of k copies of a
Denote the concatenation of X and Y by XY or...
After completing this chapter, students will be able to: Describe how the types of encryption, hashes, and digital signatures work together to provide confidentiality, integrity, and authentication; describe the mechanisms to ensure data integrity and authentication; describe the mechanisms used to ensure data
For distributed systems and networks, we often should assume that there are adversaries
Everywhere in the network
Adversary may: eavesdrop, manipulate, inject, alter, duplicate, reroute, etc…
Adversary may control a large number of network nodes that are geographically separated
Dolev-Yao Threat Model:
A very powerful adversarial model that is widely accepted as the standard by which cryptographic protocols should be evaluated
Eve, the adversary, can:
Obtain any message passing through the network
Act as a legitimate user of the network (i.e.
Chapter 9 includes content: Introduction to database security, discretionary access control (DAC), mandatory access control (MAC), role-based access control (RBAC), encryption & public key infrastructure (PKI), common attacks on databases, SQL injection, challenges of database security.
This chapter includes content: Introduction to database security, discretionary access control (DAC), mandatory access control (MAC), role-based access control (RBAC), encryption & public key infrastructure (PKI), common attacks on databases, SQL injection, challenges of database security.
Chapter 11 - Information security and computer fraud. After reading this chapter, you should be able to: Describe the risks related to information security and systems integrity, understand the concepts of encryption and authentication, describe computer fraud and misuse of AIS and corresponding risk-mitigation techniques, define vulnerabilities, and explain how to manage and assess vulnerabilities.
This chapter includes contents: To discuss security threats and attacks; to explain the fundamentals of encryption, authentication, and hashing; to examine the uses of cryptography in computing; to describe the various countermeasures to security attacks.
Bảo mật là một vấn đề lớn đối với tất cả các mạng trong môi trường doanh nghiệp ngày nay. Hacker và Intruder (kẻ xâm nhập) đã nhiều
lần thành công trong việc xâm nhập vào mạng công ty và đem ra ngoài rất nhiều thông tin giá trị. Đã có nhiều phương pháp được phát triển để
đảm bảo cho hạ tầng mạng và giao tiếp trên Internet như: sử dụng firewall, encryption (mã hóa), VPN (mạng riêng ảo)… trong đó có hệ thống
phát hiện xâm nhập.
Tuyển tập Báo cáo Hội nghị Sinh viên Nghiên cứu Khoa học lần thứ 8 Đại học Đà Nẵng năm 2012
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OpenSSH is an open-source implementation of the SSH (Secure SHell) protocols, originally developed in 1995 by Tatu Ylönen. SSH-based tools provide secure client/server connections and are usually designed to replace older remote-access tools like rsh and telnet. Unlike their predecessors, SSH-based tools encrypt their transmissions, making it difficult or impossible for intruders to “sniff” important information, such as passwords, from the data stream. SSH implementations exist for every major platform including Microsoft Windows. This paper will focus on the OpenSSH implementation....