Handbook of Applied Cryptography - chap14
Handbook of Applied Cryptography - chap14
... applications. The ef - ciency of a particular cryptographic scheme based on any one of these algebraic structures will dependonanumberoffactors, such as parametersize, time-memorytradeoffs,process- ing power ... integers can be rep- resented, and 0 has two representations. Table 14.1 illustrates the binary signed-magnitude representation of the integers in the range [7, −7]. Handboo...
Ngày tải lên: 06/11/2013, 23:15
Handbook of Applied Cryptography - chap9
... problem of preserving the integrity of a potentially large message is thus reduced to that of a small fixed-size hash- value. Since the existence of collisions is guaranteed in many-to-one mappings, ... security of a subset of the MDCs subsequently discussed in this section. Similar to the case of block ciphers for encryption (e.g. 8- or 1 2- round DES vs. 16-round DES), se...
Ngày tải lên: 17/10/2013, 16:15
Handbook of Applied Cryptography - chap10
... attacks, 5 5 Both chosen-ciphertext and chosen-plaintext attacks are of concern for challenge-response techniques based on symmetric-key encryption. Handbook of Applied Cryptography by A. Menezes, ... entropy) Suppose passwords consist of strings of 7-bit ASCII char- acters. Each has a numeric value in the range 0-1 27. (When 8-bit characters are used, val- ues 12 8-2 55comp...
Ngày tải lên: 20/10/2013, 03:15
Handbook of Applied Cryptography - chap11
... while digital signatures with appendix are applied to messages of arbitrary length. The one-way function h in Algorithm 11.5 is Handbook of Applied Cryptography by A. Menezes, P. van Oorschot ... ratio of the logarithm(base2) of the size of the signingspaceM S to the logarithm (base 2) of the size of M R , the image space of the redundancy function. Hence, the bandwidt...
Ngày tải lên: 20/10/2013, 03:15
Handbook of Applied Cryptography - chap12
... use of number of ↓ Protocol timestamps messages point-to-point key update none optional 1-3 Shamir’s no-key protocol none no 3 Kerberos KDC yes 4 Needham-Schroeder shared-key KDC no 5 Otway-Rees ... possibility of precomputation to reduce on-line computational complexity. 6. third party requirements. Considerations include (see §13.2.4): (a) requirement of an on-line (real-time), of...
Ngày tải lên: 24/10/2013, 01:15
Handbook of Applied Cryptography - chap13
... protocol run (c) off-line on-line [optional] [optional] A A A in-line TTP TTP TTP off-line Figure 13.2: In-line, on-line, and off-line third parties. In-line third parties are of particular interest ... be an on-line third party, but the certification authority is not. 13.4 Remark (pros and cons: in-line, on-line,off-line) Protocols with off-linethird parties usu- ally involve fewer real-tim...
Ngày tải lên: 28/10/2013, 09:15
Handbook of Applied Cryptography - chap15
... non-repudiation of origin (denial of being the originator of a message), non-repudiation of delivery (denial of having received a mes- sage), and non-repudiation associated with the actions of ... authentica- tion of so-called accreditation information, authentication of messages, and the signing of messages. The central authentication protocol involves a commitment-challeng...
Ngày tải lên: 28/10/2013, 09:15
Handbook of Applied cryptography
... fac- tored is of a special form; these are called special-purpose factoring algorithms. The run- ning times of such algorithmstypically depend on certain properties of the factors of n. Ex- amples ... one having a worst-case running time of O(lg 3 n) bit operations, and a sec- ond having an average-case running time of O(lg 2 n) bit operations. A more recent algo- rithm of Berns...
Ngày tải lên: 14/12/2013, 00:22