The basic facts about VoIP managementBy Miercom
VoIP analysis tools typically target particular protocol environments, such as SIP, H.323 or Cisco's SCCP (also known as "Skinny"). Interpreting different call-control protocol sequences is difficult for any one VoIP analysis tool, because the messages vary considerably depending on the protocol used.
There are two main ways of providing VoIP analysis - through real-time monitoring, which views data on the fly, or through data-capture processes, which analyze data after the fact. Real-time monitoring shows current and/or summarized statistics on active VoIP systems and best serves as a sort of security guard, watching over VoIP traffic as it moves across the wire.
Data-capture and -analysis methods record network statistics on VoIP traffic and save them for detailed review through tools designed to enhance the analysis process. Filters - the selection criteria for catching and storing VoIP data for subsequent analysis - have often provided focus for examining the statistics. Many products offer a mixture of real-time monitoring and data-capture processes.
VoIP tools can operate in one of two modes: They can be passive and simply listen to network traffic, gathering statistics in real-time (or near real-time), or actively generate traffic, and then gather and compare the results of the test transmissions. The passive approach doesn't add network overhead and can monitor the network for prolonged periods. While active tools can gauge results precisely by comparing packets created and transmitted with the results captured at the far end of the transmission.
This story, "Guide to VoIP Monitoring, Analysis, and Management" was originally published by Network World.