LiveTcpUdpWatch

LiveTcpUdpWatch is a tool for Windows that displays live information about all TCP and UDP activity on your system. Every line in the main table of LiveTcpUdpWatch displays the protocol (TCP/UDP/IPv4/IPv6), local/remote IP address, local/remote port, number of sent/received bytes, number of sent/received packets, connect/disconnect time (For TCP only), and the process (ID and path) responsible for this activity.  LiveTcpUdpWatch uses event tracing API to get live information from Windows Kernel about every TCP/UDP packet sent/received. It captures all UDP activity with process information but without the need of using a network sniffer.

http://www.nirsoft.net/utils/live_tcp_udp_watch.html