Wpcap.dll _verified_

To understand the function of wpcap.dll , one must view it within the context of the layered WinPcap architecture. The architecture consists of three primary levels:

One of the most critical features of wpcap.dll is its implementation of packet filtering. Rather than capturing all traffic and filtering it in user-space (which is computationally expensive), wpcap.dll compiles filter expressions (e.g., "tcp port 80") into BPF bytecode. This bytecode is transmitted to the NPF driver using pcap_setfilter . The driver then executes this bytecode in the kernel, discarding unwanted packets before they are copied to user-space, significantly optimizing performance. wpcap.dll