The explosive growth in computer systems and their interconnections via network has increased the dependence of both organizations and individuals on the information stored and communicated using these systems. The internet as a world wide communication network has changed our daily life in many ways. The internet, as an open forum, has created some security problems. Network security is a set of protocols that allows us to use the internet comfortably without worrying about security attacks. The most common tool for providing network security is cryptography, an old technique that has been revived and adopted to network security. In this Universal electronic connectivity, virus and hackers, electronic eavesdropping, and electronic fraud, security is paramount. This book provides a practical survey of the principles of cryptography and network security.
Additional Info
  • Publisher: Laxmi Publications
  • Language: English
  • ISBN : 978-93-81159-63-7
  • Chapter 1

    Introduction to networking Price 2.99  |  2.99 Rewards Points

    The network security and information security are often used interchangeably. Network security is generally taken as providing protection at the boundaries of an organization by keeping out intruders. Information security, however, explicitly focuses on protecting data resources from malware attack or simple mistakes by people within an organization by use of data loss prevention (DLP) techniques. One of these techniques is to compartmentalize large networks with internal boundaries.
  • Chapter 2

    Classical encryption techniques Price 2.99  |  2.99 Rewards Points

    Symmetric encryption also referred to as conventional encryption or single-key encryption was the only type of encryption in use prior to the development of public-key encryption. It remains by far the most widely used of the two types of encryption. This Part examines a number of symmetric ciphers. In this chapter, we begin with a look at a general model for the symmetric encryption process; this will enable us to understand the context within which the algorithms are used. Next, we examine a variety of algorithms in use before the computer era. Finally, we look briefly at a different approach known as steganography
  • Chapter 3

    Block ciphers and the data encryption standard Price 2.99  |  2.99 Rewards Points

    The Data Encryption Standard (DES) is a cipher (a method for encrypting information) selected as an official Federal Information Processing Standard (FIPS) for the United States in 1976, and which has subsequently enjoyed widespread use internationally. The algorithm was initially controversial, with classified design elements, a relatively short key length, and suspicions about a National Security Agency (NSA) backdoor. DES consequently came under intense academic scrutiny, and motivated the modern understanding of block ciphers and their cryptanalysis. DES is now considered to be insecure for many applications. This is chiefly due to the 56-bit key size being too small; DES keys have been broken in less than 24 hours. There are also some analytical results which demonstrate theoretical weaknesses in the cipher, although they are infeasible to mount in practice.
  • Chapter 4

    Advanced encryption standard Price 2.99  |  2.99 Rewards Points

    The principal drawback of 3DES (which was recommended in 1999, Federal Information Processing Standard FIPS PUB 46-3 as new standard with 168-bit key) is that the algorithm is relatively sluggish in software. A secondary drawback is the use of 64-bit block size. For reasons of both efficiency and security, a larger block size is desirable. In 1997, National Institute of Standards and Technology NIST issued a call for proposals for a new Advanced Encryption Standard (AES), which should have security strength equal to or better than 3DES, and significantly improved efficiency. In addition, NIST also specified that AES must be a symmetric block cipher with a block length of 128-bits and support for key lengths of 128, 192, and 256-bits.
  • Chapter 5

    Number theory Price 2.99  |  2.99 Rewards Points

    Number theory is the branch of pure mathematics concerned with the properties of numbers in general, and integers in particular, as well as the wider classes of problems that arise from their study. A number of concepts from number theory are essential in the design of public key cryptographic algorithms.
  • Chapter 6

    Public-key, cryptography and rsa Price 2.99  |  2.99 Rewards Points

    Introduction • Public-key cryptography, also known as asymmetric cryptography, is a form of cryptography in which a user has a pair of cryptographic keys—a public key and a private key. The private key is kept secret, while the public key may be widely distributed. The keys are related mathematically, but the private key cannot be practically derived from the public key. A message encrypted with the public key can be decrypted only with the corresponding private key. • Conversely, secret key cryptography, also known as symmetric cryptography uses a single secret key for both encryption and decryption. • The two main branches of public key cryptography are: • Public key encryption—a message encrypted with a recipient’s public key cannot be decrypted by anyone except the recipient possessing the corresponding private key. This is used to ensure confidentiality
  • Chapter 7

    Other public key cryptosystems Price 2.99  |  2.99 Rewards Points

    Diffie-Hellman (D-H) key exchange is a cryptographic protocol that allows two parties that have no prior knowledge of each other to jointly establish a shared secret key over an insecure communications channel. This key can then be used to encrypt subsequent communications using a symmetric key cipher. Synonyms of Diffie-Hellman key exchange include: Diffie-Hellman key agreement Diffie-Hellman key establishment Diffie-Hellman key negotiation Exponential key exchange. The scheme was first published publicly by Whitfield Diffie and Martin Hellman in 1976, although it later emerged that it had been invented a few years earlier within GCHQ, the British signals intelligence agency, by Malcolm J. Williamson but was kept classified. In 2002, Hellman suggested the algorithm be called Diffie-Hellman-Merkle key exchange in recognition of Ralph Merkle’s contribution to the invention of public key cryptography (Hellman, 2002).
  • Chapter 8

    Cryptographic hash functions Price 2.99  |  2.99 Rewards Points

    Principles of Message Authentication • Message Authentication is concerned with: – Protecting the integrity of a message – Validating identity of originator – Non-repudiation of origin (dispute resolution) In the context of communications across a networks, the following Attacks Against message security can be identified.
  • Chapter 9

    Key management and distribution Price 2.99  |  2.99 Rewards Points

    What is Kerberos? Kerberos is a network authentication protocol. It is designed to provide strong authentication for client/server applications by using secret-key cryptography. A free implementation of this protocol is available from the Massachusetts Institute of Technology. Kerberos is available in many commercial products as well. The Internet is an insecure place. Many of the protocols used in the Internet do not provide any security. Tools to “sniff” passwords off of the network are in common use by malicious hackers. Thus, applications which send an unencrypted password over the network are extremely vulnerable. Worse yet, other client/server applications rely on the client program to be “honest” about the identity of the user who is using it. Other applications rely on the client to restrict its activities to those which it is allowed to do, with no other enforcement by the server.
  • Chapter 10

    System level security Price 2.99  |  2.99 Rewards Points

    What is Intrusion Detection? Process of monitoring the events occurring in a computer system or network and analyzing them for signs of intrusion. A significant security problem for networked systems is hostile, or at least unwanted, trespass being unauthorized login or use of a system, by local or remote users; or by software such as a virus, worm, or Trojan horse.

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