Sniff-em 

Sniff-em Packet Sniffer and Network analyzer is a new network management tool designed from the ground up with ease andfunctionality in mind. An award-winning packet sniffer and network protocol analyzer.
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Router IP Console 

Router IP Console is a simple in usage SNMP-based tool intended for management and control of active network equipment (such as IP routers, repeaters etc). "Router IP Console" can raise an alarms via email on critical situations. And more...
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Monitor one 

A comprehensive, all-in-one and graphical all-in-one network monitoring software for network uptime and health monitoring. Provides sophisticated features for real-time monitoring and graphing using SNMP, trending, logging and long term analysis.
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