• United States
Neal Weinberg
Contributing writer, Foundry

Sourcefire RNA

Aug 31, 20043 mins

* Sourcefire's Real-time Network Awareness Sensor 2000

The Reviewmeister likes to keep tabs of everything happening on the network. That’s why we love Sourcefire’s Real-time Network Awareness Sensor 2000 – it’s like a magic eye that watches everything happening on your network.

By combining passive network analysis with a Web-based management system, Sourcefire delivers a powerful tool to IT personnel who need more information about their networks.

While RNA Sensors offer a wealth of information about the systems and services on your network, the downside is that it is up to you to make sense out of it all.

To help network managers understand the information from RNA Sensors and the alerts and events from the company’s intrusion-detection systems sensors (Intrusion Sensor), Sourcefire offers the Defense Center (if purchased collectively, Sourcefire refers to the package as its 3D Product Suite). RNA Sensors and Intrusion Sensors send information to the Defense Center, which provides a central view of alerts and events, network configuration information and forensic data.

RNA Sensors sit passively on the network and watch the traffic pass by. The RNA Sensor we tested had four Ethernet interfaces, but we used only one with virtual LAN-based monitoring to give RNA Sensor visibility into different parts of our production network. While this virtual LAN capability is a great feature for a network site, if you wanted to monitor multiple sites, you’d need to deploy multiple sensors.

Configuration is simple: once you tell RNA Sensor what networks to watch, it begins collecting data and populating its databases.

As RNA Sensor watches the packets fly by, it builds a model of the network topology and pinpoints the hosts on your network, the network applications  they are running, and the users and devices they are communicating with. Because RNA Sensor watches every connection to every host, it also collects information about specific network flows, such as a particular HTTP connection from a client to a server.

RNA Sensor’s information about our network was quite accurate. Application identification was excellent, as the sensor found obscure mail servers on non-standard ports and managed to get product and version information for most products.

RNA Sensor’s “policy-free” architecture is great for the sophisticated network professional, but you’ve got to have an idea of what you want to know – or combine it with Sourcefire’s Defense Center management console – before it becomes a very useful tool.

RNA Sensor offers a limited policy-compliance tool kit. As the product gathers information about systems, it generates internal events. You can search the event logs at any time, or with the policy tool kit you can build rules that watch for particular combinations of events and values. When these incidents occur, RNA Sensor will send e-mail, an SNMP trap or a syslog message.

The true power of RNA for policy compliance and monitoring comes in the Defense Center, and this is where Sourcefire hits its stride. When RNA Sensors are connected to a Defense Center console, policy-compliance rules are evaluated on the management console, which means you can combine the results from multiple sensors when writing policy rules.

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