--- service: d.root-servers.net start-period: '2015-12-21T00:00:00Z' end-period: '2015-12-21T23:59:59Z' metric: traffic-volume dns-udp-queries-received-ipv4: 4191755394 dns-udp-queries-received-ipv6: 410941712 dns-tcp-queries-received-ipv4: 28953988 dns-tcp-queries-received-ipv6: 568630 dns-udp-responses-sent-ipv4: 4173346453 dns-udp-responses-sent-ipv6: 410687366 dns-tcp-responses-sent-ipv4: 28907660 dns-tcp-responses-sent-ipv6: 568398