With Unified Payments Interface (UPI) processing over 228 billion transactions in 2025 (more than 21 billion in December alone), real-time digital payments have reached a scale where infrastructure failures are no longer isolated IT incidents but national-level risks. As transaction volumes surge, banks need resilient and intelligence-ready infrastructure that can secure every transaction and safeguard against evolving cyber threats. “Modern banking systems must be engineered for continuous availability and cryptographic assurance by design, not retrofitted after incidents occur,” Subhathra Srinivasaraghavan, vice-president at IBM India Systems Development Lab (ISDL) – the largest R&D hub in Big Blue’s infrastructure division with centres in Bengaluru, Pune and Hyderabad – tells Sudhir Chowdhary in an interview. Excerpts: