FlowViewer is a web-based netflow data analysis tool.
...FlowViewer v4.6 fixes non-UTC local time environments for FlowViewer and FlowGrapher, and $no_devices_or_exporters FlowMonitor_Collector problem.
**Note: SiLK must be v3.8.0 or later. Version 3.9 handles sFlow data.
...nfdump is a set of tools to collect and process netflow data. It's fast and has a powerful filter pcap like syntax. It supports netflow versions v1, v5, v7, v9 and IPFIX as well as a limited set of sflow. It includes support for CISCO ASA (NSEL) and CISCO NAT (NEL) devices, which export event logging records as v9 flows.
nfdump is fully IPv6 compatible.