Non-repudiation ensures that neither party can deny the authenticity of their electronic communications or transactions. This is achieved through methods such as digital signatures, which provide proof of origin and verify that the content has not been tampered with. Integrity ensures that data has not been altered, but does not prevent denial of participation in the communication. Confidentiality ensures information is not disclosed to unauthorized individuals, but does not necessarily prove who was involved in the exchange. Availability ensures that systems and data are accessible when needed, but does not address the issue of denying the transaction.