A minimum-knowledge scheme allows a claimant to prove its identity to a verifier without disclosing any secret information. Minimum-knowledge schemes, incorporating identity verification, signature generation and verification, are generally based on interactive proofs. The Ohta-Okamoto minimum-knowledge identification and signature scheme is characterised by a good balance between the claimant's storage requirements and the time to perform a verification. This makes it particularly suitable for use with minimum storage devices such as smart cards. This paper presents a realisation of an Ohta-Okamoto based minimum knowledge and signature scheme, ranging over identity verification, signature generation and verification. The modular arithmetic functions, such as: multiplication, division, exponentiation and multiplicative inverse, as well as prime number generation, pseudo random number generation and hashing function are detailed. An analysis of the realised scheme is presented, including a comparison with the Fiat-Shamir identification scheme.