Question: What is the minimum recommended key length for Diffie-Hellman MODP groups in IKEv2 for IPsec SA negotiation, as per Network Domain Security (NDS) guidelines?
Option 1: 1024-bit
Option 2: 1536-bit
Option 3: 2048-bit
Option 4: 4096-bit
Explanation: As per the provided context, for security reasons, the use of Diffie-Hellman MODP groups less than 2048-bit shall not be supported. This implies that 2048-bit is the minimum recommended key length to ensure adequate security in IKEv2 negotiations for IPsec SA establishment within telecom networks, aligning with Network Domain Security (NDS) best practices.