operating system and network security ppt

... CERT® Guide to System and Network Security Practices Networks have become indispensable for conducting business in government, commer-cial, and academic organizations Networked systems allow you ... that are networked, distributed, and hetero-geneous needs to care about improving the security of networked systems Whether you acknowledge it or not, your organization’s networks and systems ... are operating all systems securely But this may not be the case System and network admin-istrators typically have insufficient time, knowledge, and skill to address the wide range of demands

Ngày tải lên: 14/03/2014, 22:20

... Depending on the operating system volved, intruders can access privileged data without a password, andcan create privileged database or system accounts or even run arbi-trary system commands The intruder ... 721some kind of native authentication system that handles its own usernameand password system However, well-designed systems can be configured toswitch that off and simply use the preauthenticated ... database, and the pro-gramming language used for dynamic content The most common com- bination is LAMP: Linux, Apache, MySQL, and Perl LAMP can also stand for Linux, Apache, MySQL, and PHP; and for

Ngày tải lên: 14/08/2014, 14:21

... Trang 1Computer and Network Essential TRUNG TÂM ĐÀO TẠO MẠNG MÁY TÍNH NHẤT NGHỆ 105 Bà Huyện Thanh Quan - 205 Võ Thị ... printer, – Input Devices : Keyboard, Mouse, – Multi-Media (CD-ROM, Sound,…) – Communication (Network, I/O Port, ) Mối quan hệ giữa các khối Trang 3II THÀNH PHẦN VẬT LÝ 1 CPU - Central Processing ... loại : Sound card / Micro / HeadPhone Trang 277 Communication Devices – Các cổng I/O : LPT, COM, Network Interface, Modem, Router ADSL Trang 338 Main Board (Mother Board) phần Trang 369 Computer

Ngày tải lên: 23/12/2013, 04:18

... Wired and Wireless Networks, Kameswari Chebrolu and Bhaskaran Raman, 09-13 May 2005 Cryptography and Network Security Bhaskaran Raman Department of CSE, IIT Kanpur Reference: Whitfield Diffie and ... of Wired and Wireless Networks, Kameswari Chebrolu and Bhaskaran Raman, 09-13 May 2005 Security Guarantees ● Two possibilities: – Unconditional – Computational security ● Unconditional security: ... tape ● Most systems have computational security – How much security to have? – Depends on cost-benefit analysis for attacker Fundamentals of Wired and Wireless Networks, Kameswari Chebrolu and Bhaskaran

Ngày tải lên: 05/03/2014, 23:20

... detection, security audit trails, security recovery Trang 17Model for Network SecurityTrang 18Model for Network Security using this model requires us to: use the transformation and secret information ... communicating open systems, which ensures adequate security of the systems or of data transfers” “a processing or communication service provided by a system to give a specific kind of protection to system ... information Trang 6Security TrendsTrang 7OSI Security Architecture ITU-T X.800 “Security Architecture for OSI”  defines a systematic way of defining and providing security requirements  for us it provides

Ngày tải lên: 06/03/2014, 16:20

... Cryptography and Cryptography and Network Security Network Security Chapter 2 Chapter 2 Fourth Edition Fourth Edition by William Stallings by ... plaintext  select plaintext and obtain ciphertext select plaintext and obtain ciphertext  chosen ciphertext  select ciphertext and obtain plaintext select ciphertext and obtain plaintext  chosen ... letter is replaced by the letter in the same row and in the column of the other letter of the pair Security of Playfair Cipher      security much improved over monoalphabetic since

Ngày tải lên: 06/03/2014, 16:20

... Trang 1Cryptography and Network Security Chapter 8 Fourth Edition by William Stallings Lecture slides by Lawrie Brown Trang ... factors of 8 are 1,2,4,8 and of 15 are 1,3,5,15 and 1 is the only common factor  conversely can determine the greatest common divisor by comparing their prime factorizations and using least powers ... Theorem ap-1 = 1 (mod p)  where p is prime and gcd(a,p)=1  also known as Fermat’s Little Theorem  also ap = p (mod p)  useful in public key and primality testing Trang 7Euler Totient Function

Ngày tải lên: 06/03/2014, 16:20

... Trang 1Cryptography and Network SecurityChapter 9 Fourth Edition by William Stallings Trang 2Chapter 9 – Public Key Cryptography and RSAEvery Egyptian received two names, ... received two names, which were known respectively as the true name and the good name, or the great name and the little name; and while the good or little name was made public, the true or great ... bits)  security due to cost of factoring large numbers Trang 13RSA Key Setup each user generates a public/private key pair by:  selecting two large primes at random - p, q  computing their system

Ngày tải lên: 06/03/2014, 16:20

... Software Security / Malicious Code – Buffer overflows, viruses, worms, protection mechanisms • System Security – Hacker behavior, intrusion & anomaly detection, hacker and admin tools • Networks ... understanding of the tradeoffs involved • Is Internet Explorer secure enough? – Depends on context 1/9 /0 7 CIS/ TCOM 551 19 How to think... software and function of the system Separate security ... computer – Physical aspects of security • Controlling who is allowed to make changes to a computer system (both its hardware and software) – Social aspects of security 1/9 /0 7 CIS/

Ngày tải lên: 14/03/2014, 20:20

... CS595-Cryptography and Network Security Cryptography and Network Security Xiang-Yang Li CS595-Cryptography and Network Security CS595-Cryptography and Network Security Introduction The ... Tzu CS595-Cryptography and Network Security Information Transferring CS595-Cryptography and Network Security Attack: Interruption CS595-Cryptography and Network Security Attack: Interception CS595-Cryptography and ... Interception CS595-Cryptography and Network Security Attack: Modification CS595-Cryptography and Network Security Attack: Fabrication CS595-Cryptography and Network Security Attacks, Services and Mechanisms ! Security

Ngày tải lên: 14/03/2014, 20:20

... Louis Aspects of Security Aspects of Security   Aspects of information security: Aspects of information security:   Security attack Security attack   Security mechanism Security mechanism   Security ... sci.crypt.random-numbers alt.security comp.security.misc, comp.security.firewalls, comp.security.announce comp.risks comp.virus Security and Cryptography Forum, http://forums.devshed.com/security -and ... Architecture for OSI Security Architecture for OSI ” ”   Defines a systematic way of defining and providing Defines a systematic way of defining and providing security requirements security requirements   Provides

Ngày tải lên: 14/03/2014, 22:20

... Cryptography and Cryptography and Network Security Network Security Chapter 10 Chapter 10 Fourth Edition Fourth Edition by William ... keys: agree on prime q=353 and a=3 select random secret keys:   compute respective public keys:    A... Key Exchange Protocols     users could create random private/public D-H keys ... key and their identity B generates a session key K sends it to A encrypted using the supplied public key A decrypts the session key and both use problem is that an opponent can intercept and

Ngày tải lên: 15/03/2014, 17:20

... Trang 1Cryptography and Network SecurityChapter 13 Fourth Edition by William StallingsLecture slides by Lawrie Brown Trang ... Algorithm (DSA)  creates a 320 bit signature  with 512-1024 bit security  smaller and faster than RSA  a digital signature scheme only  security depends on difficulty of computing discrete logarithms ... Creation to sign a message M the sender:  generates a random signature key k, k<q  nb k must be random, be destroyed after use, and never be reused  then computes signature pair: r = (g

Ngày tải lên: 15/03/2014, 17:20

... (typically 16 rounds) to form the full cipher Trang 19Data Encryption StandardStandards, now the National Institute of Standards and Technology 56-bit key Trang 20Ø Uses only 56 bits key§ Possible ... substitution-permutation (S-P) networks, which now form the basis of modern block ciphers Ø An S-P network is the modern form of a substitution-transposition product cipher Ø S-P networks are based on ... 12Substitution-permutation Network Trang 13Confusion and Diffusionq Confusion Ø A technique that seeks to make the relationship between the statistics of the ciphertext and the value of the encryption

Ngày tải lên: 22/03/2014, 14:20

... on confidentiality and integrity requirements – Mandatory access control incorporated into the major subsystems of the kernel • Limit tampering and bypassing of application security mechanisms ... 17Implementing Multilevel Security• Dynamic: – Tag all values in memory with their security level – Operations propagate security levels – Must be sure that tags can’t be modified – Expensive, and approximate ... equal) security label • Write: C(S) ≤ C(O) • Example: A user with Secret clearance can: – Read objects with label Public and Secret – Write/create objects with label Secret Trang 9Multilevel Security

Ngày tải lên: 22/03/2014, 15:21

... exploits • eavesdropping and sniffing • attackers listen for userids and passwords and then just walk into target systems • as a result the IAB included authentication and encryption in the next ... Cryptography and Network Security Third Edition by William Stallings Lecture slides by Lawrie Brown The need • In CERTs 2001 annual report it listed 52,000 security incidents • the ... to gateway security Transport & Tunnel Modes Encapsulating Security. .. and Key Management Protocol (RFC 2407) • provides framework for key management • defines procedures and packet formats

Ngày tải lên: 23/03/2014, 00:20

... important network security tools and applications, including Kerberos, X.509v3 certificates, PGP, S/MIME, IP Security, SSL/TLS, and SET. Part Four. System Security: Looks at system- level security ... affected security is the introduction of distributed systems and the use of networks and communications facilities for carrying data between terminal user and computer and between computer and computer. ... network security have developed. This text provides a practical survey of both the principles and practice of cryptography and network security. First, the basic issues to be addressed by a network...

Ngày tải lên: 18/02/2014, 08:20

... of data main use is sending a few blocks of data Cryptography and Cryptography and Network Security Network Security Chapter 6 Chapter 6 Fourth Edition Fourth Edition by William Stallings by ... in security nb encrypt & decrypt equivalent in security  if if K1=K2 K1=K2 then can work with single DES then can work with single DES  standardized in ANSI X9.17 & ISO8732 standardized ... stream)  have a pseudo random have a pseudo random keystream keystream  combined (XOR) with plaintext bit by bit combined (XOR) with plaintext bit by bit  randomness of randomness of stream...

Ngày tải lên: 06/03/2014, 16:20

... by “ created by “ Pseudorandom Number Generators Pseudorandom Number Generators (PRNGs)” (PRNGs)” Cryptography and Cryptography and Network Security Network Security Chapter 7 Chapter ... are not truly random although are not truly random  can pass many tests of “randomness” can pass many tests of “randomness”  known as “pseudorandom numbers” known as “pseudorandom numbers”  created ... PRG Natural Random Noise Natural Random Noise  best source is natural randomness in real world best source is natural randomness in real world  find a regular but random event and monitor...

Ngày tải lên: 06/03/2014, 16:20

... Comprehensive Guide to Network Security page 33 Network Layer The network layer describes how systems on different network segments find each other; it also defines network addresses. A network address ... connected systems. Note The network address is assigned by the network administrator and should not be confused with the MAC address assigned to each network card. The purpose of a network address ... isolation from other networking activities. This book provides system and network administrators with the information they will need to run a network with multiple layers of security protection,...

Ngày tải lên: 11/12/2013, 03:15