Question: What is the primary consideration for designing cryptographic algorithms in 3GPP security, in terms of their lifespan and resistance to attacks?
Option 1: Ensuring algorithms can be easily updated every 5 years to maintain security, with a focus on preventing attacks that require at least half the workload of an exhaustive key search.
Option 2: Designing algorithms to remain secure for at least 20 years, making successful attacks with less than the workload of an exhaustive key search through the effective key space impossible.
Option 3: Allowing for periodic security audits every 10 years to assess algorithm strength, with an initial design focus on thwarting only the most common types of attacks.
Option 4: Prioritizing algorithm simplicity to facilitate widespread adoption, assuming security updates can be pushed as needed within a 15-year window.
Explanation: The correct answer reflects the requirement for long-term security and high resistance to attacks. Designing algorithms with a strength that ensures successful attacks are impossible with less than the workload of an exhaustive key search through the effective key space, for at least 20 years, aligns with the qualitative requirements for resilience in 3GPP security. This approach prioritizes future-proofing cryptographic functions against evolving threats.