dnscap is a network capture utility designed specifically for DNS traffic. It produces binary data in pcap(3) format. This utility is similar to tcpdump(1), but has a number of features tailored to DNS transactions and protocol options. OARC likes to use dnscap for DITL data collections. Some of its features include: + Understands both IPv4 and IPv6 + Captures UDP, TCP, and IP fragments. + Collect only queries, responses, or both (-s option) + Collect for only certain source/destination addresses (-a -z -A -Z options) + Periodically creates new pcap files (-t option) + Spawns an upload script after closing a pcap file (-k option) + Will start and stop collecting at specific times (-B -E options)