DPDK provides a framework for high-performance packet processing in user space, bypassing the kernel's networking stack. The BlueField DPU's PMD (Poll Mode Driver) allows DPDK applications to directly access the network interface with minimal overhead. This is ideal for DPI applications that need to process a large volume of packets at high speed. Standard socket APIs and Netfilter hooks involve kernel intervention, which can introduce significant overhead. Libpcap is a packet capture library, not designed for high-performance packet processing. 'tcpdump' is a command-line tool, not a programming API.