Besides Wireshark what are some tools for monitoring network congestion? We are having network issues and want to be absolutely sure it's our ISP.
Orion NetFlow Traffic Analyzer from Solarwinds is a tool that identifies "who & what are consuming your bandwidth". There is a free trial, while the real product starts at €1400.
Solarwinds has an array of excellent network tools.
Snot is an open source "tool to identify and analyze network congestion."