How NBAs work/h2>
"NBA products use collectors, which can be stand-alone servers or appliances, to which Netflow, IPFIX or sFlow data is sent," says Phil Hochmuth, senior analyst of enterprise research at the Yankee Group.
"When Netflow data is sent to a collector, basically, all of the packet header information processed by the network node is collected and sent. Think of it as a shipping log for that network device. As NBA products collect data from all network devices with flow-data support, a larger picture emerges of what's happening on the network," such as which IP addresses are talking to each other, how often, what applications are running over the network.
NBA tools also provide other features beyond basic flow data collection, Hochmuth says. These products can discover and map all devices -- from clients to servers, switches, and routers -- across an IP network. With all of the network devices accounted for, and all "shipping logs" collected from routers and switches, NBA tools also perform sophisticated network traffic analysis. Users can create baseline performance models for network behavior, identify areas of congestion or underutilization, and -- most important to security -- detect traffic anomalies.
Gartner Analyst Paul Proctor adds, "NBA systems analyze network traffic with data gathered from sources such as Cisco's NetFlow and Juniper's cFlow or sources that support the sFlow standard. Data may also be correlated directly from packet analysis. They use a combination of deterministic (signature) and non-deterministic (anomaly) detection to alert network and security managers of suspicious activity and present a picture of network activity for analysis and response. Fundamentally, NBAs are a window into the behavior of a network and require a knowledgeable operator to interpret their output." -Nancy Sartain