Explanation: PowerProtect DD appliances allow direct data writing from backup clients, which improves efficiency and data transfer rates, leveraging DD Boost and other protocols for optimized backup performance without intermediate processing. In a PowerProtect DD backup infrastructure, backup clients are designed to write data directly to the appliance. This direct write capability is supported by protocols like DD Boost, which enhances the backup performance by offloading deduplication to the client side, reducing network bandwidth usage and speeding up backups. PowerProtect DD systems are optimized to handle direct data ingestion from backup clients, streamlining the data protection process without requiring intermediate storage or decompression steps. This feature simplifies the backup architecture and improves data protection efficiency.