Thus typically there are vendor-specific tools, such as CiscoWorks, Extreme Enterprise Manager, or HP Insight Manager (more a server than network tool) that are tailor-made to help configure and monitor devices very precisely. These are used more for provisioning, maintenance, code updates, etc.
Then typically companies use a more general SNMP monitoring and alert platform, so the folks in the operations center see when Topeka goes off-line. Tools such as EMC Ionix and IBM Tivoli are generally found up on the screen in the operations center, and are used as the day-to-day dashboard, and also typically used to generate uptime and response-time metrics for SLAs. These tools are sometimes used more to manage/monitor servers and databases, but are often used for the network as well.
Also for the day-to-day monitoring some companies I've worked with use tools like Cisco IOS NetFlow to monitor traffic flows in real-time for Cisco shops (and there are similar NetFlow flavors for Juniper - jFlow, HP - NetStream, etc.).
The makeup and mix of tools needed varies a lot depending on the overall scale/scope/design of the network. A small one-location enterprise will have vastly different needs than a hosting company or eCommerce provider, of course.
And then of course there are the specialized test and simulation tools, everything from impairment generators, to protocol analyzers and even wireless test and measurement tools.
