摘要:
A method of transmitting messages from a sender to a recipient over a wireless channel, the messages including a sequence counter and a frame counter. The method comprises establishing initial values of the sequence counter and the frame counter at the sender. Initial values of the frame counter and the sequence counter are provided to the recipient. The sender sends compressed messages including the value of the sequence counter and not the frame counter and monitors for an acknowledgement of receipt by the recipient. When no acknowledgment is received, the sender sends uncompressed messages until an acknowledgement of receipt is received from the recipient. The sequence counter is incremented and the next value of the frame counter is established as the integer next larger than previous value of the frame counter which is congruent to the sequence counter modulo 256.
摘要:
A password protocol uses a multiple word password and provides prompts to a user allowing the user to select the next word in the password from a set of words. The selection of a word causes a client to perform a cryptographic operation and generate a new selection of words. After the password is completely entered, a key is generated from the words selected.
摘要:
A method of communicating in a secure communication system, comprises the steps of assembling a message at a sender, then determining a security level, and including an indication of the security level in a header of the message. The message is then sent to a recipient.
摘要:
There are disclosed systems and methods for reducing the number of computations performed by a computing device constructing a public key from an implicit certificate associated with a certificate authority in an implicit certificate scheme. In one embodiment, the device first operates on the implicit certificate to derive an integer e. The device then derives a pair of integers (e1, e2) from the integer e, such that each of the pair of integers (e1, e2) has a bit length less than the bit length of the integer e, and such that the ratio of the pair of integers (e1, e2) corresponds to the integer e. The device then computes the public key by combining the integers e1 and e2 with public key contribution data derived from the implicit certificate and a public key of the certificate authority.
摘要:
A method and system for distributed security for a plurality of devices in a communication network, each of the devices being responsible for generating, distributing and controlling its own keys for access to the communication network and using the keys to establish a trusted network, each device's membership to the communication network being checked periodically by other devices by using a challenge response protocol to establish which devices are allowed access to the communication network and the trusted network.
摘要:
The present invention provides a new trapdoor one-way function. In a general sense, some quadratic algebraic integer z is used. One then finds a curve E and a rational map defining [z] on E. The rational map [z] is the trapdoor one-way function. A judicious selection of z will ensure that [z] can be efficiently computed, that it is difficult to invert, that determination of [z] from the rational functions defined by [z] is difficult, and knowledge of z allows one to invert [z] on a certain set of elliptic curve points. Every rational map is a composition of a translation and an endomorphism. The most secure part of the rational map is the endomorphism as the translation is easy to invert. If the problem of inverting the endomorphism and thus [z] is as hard as the discrete logarithm problem in E, then the size of the cryptographic group can be smaller than the group used for RSA trapdoor one-way functions.
摘要:
A method is disclosed for performing key agreement to establish a shared key between correspondents and for generating a digital signature. The method comprises performing one of key agreement or signature generation, and using information generated in said one of key agreement or signature generation in the other of said key agreement or said signature generation. By doing this, computations and/or bandwidth can be saved.
摘要:
A method of formatting data for transmission to another party including the step of incorporating in the data a flag indicative of the absence of data for authentication of the sender. An authentication tag length is also included to permit variable length tags to be used.
摘要:
A method of communicating in a secure communication system, comprises the steps of assembling as message at a sender, then determining a security level, and including an indication of the security level in a header of the message. The message is then sent to a recipient.
摘要:
There are disclosed systems and methods for reducing the number of computations performed by a computing device constructing a public key from an implicit certificate associated with a certificate authority in an implicit certificate scheme. In one embodiment, the device first operates on the implicit certificate to derive an integer e. The device then derives a pair of integers (e1, e2) from the integer e, such that each of the pair of integers (e1, e2) has a bit length less than the bit length of the integer e, and such that the ratio of the pair of integers (e1, e2) corresponds to the integer e. The device then computes the public key by combining the integers e1 and e2 with public key contribution data derived from the implicit certificate and a public key of the certificate authority.