The DES algorithm has been considered insecure for some time due to its short key length and susceptibility to brute-force attacks. When seeking a more secure symmetric encryption algorithm, AES (Advanced Encryption Standard) is the recommended choice. AES is widely recognized for its strength and efficiency, particularly in its most common configuration of a 128-bit block size with key sizes of 128, 192, or 256 bits123.

AES is used by the U.S. government for securing classified information and is implemented in software and hardware throughout the world to encrypt sensitive data. Its security is based on the difficulty of the AES problem in cryptography, which involves the AES block cipher algorithm. The algorithm’s design and strength against all known attacks make it suitable for highly sensitive data protection.

References: For a strong encryption algorithm, AES is often recommended in security guidelines and courses, including those provided by the EC-Council for Application Security Engineers specializing in Java. While I cannot provide direct references to EC-Council’s proprietary materials, the use of AES for secure coding practices is a standard recommendation across various cybersecurity training programs and documents. For detailed study, one would refer to EC-Council’s CASE Java courses and study guides that cover encryption and secure coding practices.