根据给定的主题和关键字，编写一篇论文。
主题：网络安全
关键字：密码学、网络攻击、恶意软件、身份验证
With the increasing reliance on technology, network security has become a central concern for organizations and individuals alike. Cryptography is a key tool in ensuring secure communication between parties, especially through encryption of sensitive information. However, network attacks and malware remain common threats, requiring constant vigilance and up-to-date defenses. Effective authentication measures, such as two-factor authentication, can help prevent unauthorized access to networks and data. Overall, a multi-faceted approach including education, risk assessment, and proactive measures is necessary to ensure robust network security.