What principle does nonrepudiation support in communication systems?

Nonrepudiation fundamentally supports the principle of accountability in communication systems. This principle ensures that an individual or organization cannot deny the validity of their actions or the transmission of information. In the context of communication systems, nonrepudiation is achieved through mechanisms such as digital signatures and encryption, which provide proof of the origin, integrity, and receipt of the message.

By establishing nonrepudiation, stakeholders can be held accountable for their interactions and transactions, as the evidence gathered (such as timestamped logs and signatures) reinforces the ability to trace actions back to their sources. This accountability is crucial in various applications, including e-commerce, legal communications, and secure data exchanges, where it is essential to resolve disputes and ensure compliance with regulations.

The other options do not directly align with the concept of nonrepudiation. Scalability refers to the system's ability to handle growing amounts of work or its potential to accommodate growth, while transparency pertains to open and clear operations within a system. Accessibility focuses on the ease with which users can reach and utilize resources or services, which is not inherently related to the principle of nonrepudiation.