February 28, 2011, 12:16 PM — Security information and event management (SIEM) equipment is valuable for getting a bird's-eye view of security in the enterprise, but there are deployment challenges that IT security managers need to recognize.
Reed Smith LLP, a large law firm that operates four data centers and about two dozen offices worldwide, has been progressing through an enterprisewide deployment of HP's SIEM product, ArcSight. It consolidates and correlates input from firewalls, intrusion-prevention systems, servers, antivirus, vulnerability scanners, routers and more, including capturing NetFlow data. The firm is getting a better real-time picture of network activity, not just threats but server availability, for instance.
However, like exercising to get stronger, SIEM has some "no pain, no gain" aspects. Work has to go into properly activating a SIEM, according to Eric Mazurak, network and security engineer at Reed Smith.
"There will be a high false positive rate if you don't do fine tuning," says Mazurak, adding, "the more logging you do, the more tuning is involved." Basically, that involves getting a thorough understanding of the SIEM interface and making changes to out-of-the box rules so that the SIEM is making the most accurate assessment it can. Mazurka recommends test-driving a SIEM for a while in a production network before committing to a purchase. Once the SIEM is in, it will need continuing maintenance, he adds.
The data a SIEM relies on will be flowing in constantly from any source supported by the SIEM connectors that collect and "normalize" the information so the SIEM can process it. If the SIEM vendor already has these software connectors for the variety of network resources you monitor, that's fine. But that's not always the case. Sometimes you might have to pay a SIEM vendor to write a connector, or do it yourself, to support specific network or security products you use. So it's important to find out if a SIEM vendor is able to support custom-coding work. ArcSight also has SIEM connectors available in an appliance form, he adds.
The SIEM connectors collecting and "normalizing" input from a wide range of other products raise another issue, Mazurak points out. These connectors have to be updated and changed whenever the products themselves are updated or changed. So it's important to understand the SIEM vendor's track record in doing this and be confident the vendor will be making these adjustments in terms of software updates in the future.