Throttled Pro - Throttled Pro optimizes your internet connection and provides QoS (Quality of Service) to Mac OS X.
Zabbix - Track, record, alert and visualize performance and availability of IT resources
Ashampoo Internet Accelerator - Ashampoo Internet Accelerator is an internet connection optimizer and booster that allows you to tune your connection settings.
Datadog - See metrics from all of your apps, tools & services in one place with Datadog's cloud monitoring as a service solution. Try it for free.
Net Speed Booster - Net Speed Booster is an internet speed optimization tool that lets you tweak your internet settings and make them up to the mark.
Nagios - Complete monitoring and alerting for servers, switches, applications, and services