Xem 1-20 trên 32 kết quả Encryption techniques
  • Lecture 2: Classical encryption techniques. This chapter includes contents: Basic vocabulary of encryption and decryption, building blocks of classical encryption techniques, caesar cipher, the swahili angle, monoalphabetic ciphers, the all-fearsome statistical attack, multiple-character encryption to mask plaintext structure, another multi-letter cipher, polyalphabetic ciphers,...

    pdf54p estupendo4 24-08-2016 1 1   Download

  • Block ciphers are among the most widely used types of cryptographic algorithms provide secrecy and/or authentication services in particular will introduce DES (Data Encryption Standard)

    ppt40p muathu_102 28-01-2013 17 4   Download

  • LANs, WANs, WLANs are known as edge networks May be contained within businesses or homes Needs to be protected from the rest of the Internet! Why firewall? Encryption? Cannot stop malicious packets from getting into an edge network Authentication? Can determine whether an incoming IP packet comes from a trusted user However, not all host computers have resources to run authentication algorithms Host computers managed by different users with different skill levels.

    ppt38p doilan 26-01-2013 24 2   Download

  • 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...

    ppt25p muathu_102 28-01-2013 17 2   Download

  • Often a security tool does exactly what you want, right out of the box. More frequently, you need to customize the tool to fit the needs of your network structure. Network Security Tools shows experienced administrators how to modify, customize, and extend popular open source security tools such as Nikto, Ettercap, and Nessus.

    pdf2690p muathu_102 28-01-2013 72 44   Download

  • to defend company resources: not only passively by using firewalls, virtual private networks (VPNs), encryption techniques, and whatever other tricks, but also by deploying proactive tools and devices throughout the network = IDS.

    ppt34p vvnghi 05-05-2011 90 18   Download

  • Intrusion detection is not for the faint at heart. But, if you are a network administrator chances are you're under increasing pressure to ensure that mission-critical systems are safe--in fact impenetrable--from malicious code, buffer overflows, stealth port scans, SMB probes, OS fingerprinting attempts, CGI attacks, and other network intruders.

    pdf1401p muathu_102 28-01-2013 33 16   Download

  • William Stallings' Cryptography and Network Security: Principles and Practice, 5e is a practical survey of cryptography and network security with unmatched support for instructors and students.

    pdf3551p muathu_102 28-01-2013 38 8   Download

  • Threat Discovery Services provides corporatewide traffic threat detection and analysis capabilities via a threat discovery appliance or any VMware-based system. It is deployed out of band at the network layer on the core switch, where it can monitor the stealth techniques being used by modern malware to provide 24 x 7 network monitoring and detection of hidden malware infections. The threat discovery technology detects day-zero infections by leveraging Trend Micro Smart Protection Network and multiple threat analysis engines.

    pdf10p khongmuonnghe 04-01-2013 18 3   Download

  • Web now widely used by business, government, individuals but Internet & Web are vulnerable have a variety of threats integrity confidentiality denial of service authentication need added security mechanisms

    ppt14p doilan 26-01-2013 28 3   Download

  • As our society grows ever more reliant on computers, so it also becomes more vulnerable to computer crime. Cyber attacks have been plaguing computer users since the 1980s, and computer security experts are predicting that smart telephones and other mobile devices will also become the targets of cyber security threats in the future.

    pdf0p muathu_102 28-01-2013 28 3   Download

  • WPA: A rush solution to the security problems of WEP WPA2: Based on 802.11i (official version) Encrypt and authenticate MSDUs: counter mode-CBC MAC protocol with AES-128 Authenticate STAs: 802.1X Initialization vectors transmitted in plaintext are no longer needed to generate per-frame keys But most of the existing Wi-Fi WPA cards cannot be upgraded to support 802.11i

    ppt28p muathu_102 28-01-2013 18 3   Download

  • Intruders Intrusion Techniques Password Protection Password Selection Strategies Intrusion Detection Viruses and Related Threats Malicious Programs The Nature of Viruses Antivirus Approaches Advanced Antivirus Techniques Recommended Reading and WEB Sites

    ppt36p muathu_102 28-01-2013 18 3   Download

  • What is Intrusion? E.g. Malice gets Alice’s user name & password and impersonates Alice Intruders are attackers who obtain login information of legitimate users and impersonate them

    ppt39p doilan 26-01-2013 15 2   Download

  • In the last lecture we looked at some high-level descriptions of key distribution and agreement schemes. These protocols cannot be used as they were stated. In implementation of the actual protocol, there are many situations one should be careful of. In this lecture, we will look at some common protocol failures that arise when trying to implement security protocols We will then look at some specific examples of security protocols

    ppt30p muathu_102 28-01-2013 14 2   Download

  • Advanced Encryption Standard competition began in 1997 Rijndael was selected to be the new AES in 2001 AES basic structures: block cipher, but not Feistel cipher encryption and decryption are similar, but not symmetrical basic unit: byte, not bit block size: 16-bytes (128 bits) three different key lengths: 128, 192, 256 bits AES-128, AES-192, AES-256 each 16-byte block is represented as a 4 x 4 square matrix, called the state matrix the number of rounds depends on key lengths 4 simple operations on the state matrix every round (except the last round) ...

    ppt38p muathu_102 28-01-2013 13 2   Download

  • To use data encryption algorithms in network communications, all parities must first agree on using the same secret keys Rely on couriers Set up a meeting to determine a secret key Use postal service, email service, phone service … However, these conventional methods are inflexible for network communication applications Public-key cryptography (PKC) Invented in the 1970’s Without the need of sharing prior secrets to distribute secret keys securely Can also be used for authentication

    ppt39p muathu_102 28-01-2013 31 2   Download

  • Encryption and authentication algorithms are building blocks of secure network protocols Deploying cryptographic algorithms at different layers have different security effects Where should we put the security protocol in the network architecture?

    ppt27p muathu_102 28-01-2013 22 2   Download

  • Radio based communication, open air The attacker, having a radio transmitter and receiver with the same radio frequency of the underlying wireless network, can easily: Intercept wireless data Connect his computing devices to a nearby wireless network Inject new packets to an existing wireless network Jam a particular wireless channel using a jamming device Security measures Implement encryption algorithms, authentication algorithms, and integrity-check algorithms at the data-link layer Provide network access with wired equivalent privacy Higher-layer protocols and applications can be used ...

    ppt32p muathu_102 28-01-2013 18 2   Download

  • have a range of application specific security mechanisms eg. S/MIME, PGP, Kerberos, SSL/HTTPS however there are security concerns that cut across protocol layers would like security implemented by the network for all applications

    ppt23p doilan 26-01-2013 17 1   Download

Đồng bộ tài khoản