Flow-tools is library and a collection of programs used to collect, send, process, and generate reports from NetFlow data. The tools can be used together on a single server or distributed to multiple servers for large deployments. The flow-toools library provides an API for development of custom applications for NetFlow export versions 1,5,6 and the 14 currently defined version 8 subversions. A Perl and Python interface have been contributed and are included in the distribution. Commands that utilize the network use a localip/remoteip/port designation for communication. "localip" is the IP address the host will use as a source for sending or bind to when receiving NetFlow PDU’s (ie the destination address of the exporter. Configuring the "localip" to 0 will force the kernel to decide what IP address to use for sending and listen on all IP addresses for receiving. "remoteip" is the destination IP address used for sending or the expected address of the source when receiving. If the "remoteip" is 0 then the application will accept flows from any source address. The "port" is the UDP port number used for sending or receiving. When using multicast addresses the localip/remoteip/port is used to represent the source, group, and port respectively.