Abstract: Public data including a prime number p, a natural number d, a matrix Q, and a matrix S are acquired by a public data acquisition section, and secret key including natural numbers nA, kA is generated by a shared secret key generation section. A matrix MA (MA=S?kAQnASkA) is calculated by a non-commutative matrix generation section and transmitted to a communication party, and a matrix MB (MB=S?kBQnBSkB) is acquired from the communication party. A matrix MAB (MAB=S?kAMBnASkA) is computed as a common secret key by a shared secret key computation section. An encryption/decryption device is thereby capable of rapid generation of the secure common secret key.

Abstract: An encryption device generates non-commutative matrices A1, A2 based on private data A and prime numbers p1, p2, and operates the non-commutative matrices A1, A2 on vectors vi1, vi?12. The encryption device performs non-linear transformation to transform the vectors vi1, vi2 into bit sequences, and joins these to the bit sequences W1, W2. The encryption device repeats the operation of the non-convertible matrices and the non-linear transformation until the respective numbers of bits of the bit sequence W1 and the bit sequence W2 have reached a number of bits of a bit sequence expressing encryption target data. The encryption device derives a pseudo-random number bit sequence by computing the exclusive logical sum between the bit sequence W1 and the bit sequence W2, and performs encryption using the pseudo-random number bit sequence.

Abstract: A transportable data system includes two units (3, 4) which are fitted in a rigid case which includes a lid (2) and a bottom part. When the lid is closed, the one unit (3), which is supported by a carrier plate, is located above the other unit (4), whereas when the case is open, with the lid substantially vertical, the one unit can be moved towards and partially into the lid, so as expose the other unit (4) and bring it to a working position. Provided are two separate side - walls (14, 15) which are fitted firmly to the bottom part (1), and each of which has an upper guide rail (6, 7). The guide rails are parallel with the bottom part and also with one another. Furthermore, the carrier plate (5) is displaceably mounted on the guide rails.

Abstract: A portable data system includes a bottom plate 1 and a lid 4. The bottom plate carries a PC-computer 10 having a keyboard 11 and a pivotal presentation screen 12 which in its lowered position forms part of the upper surface of the computer. The system also includes a voltage source for powering the computer and the screen. A carrier plate 26 is intended to rest on the upper surface of the screen in the lowered position thereof. The carrier plate is attached to the bottom plate by means of two parallel-arm mechanisms 18-21 arranged on each side of the computer. These parallel-arm mechanisms enable the carrier plate together with the printer 27 carried thereby to be moved away from the computer and partially into the raised lid.