Q: What are you most concerned about or focused on in terms of security right now?
SW: Like everyone else, we worry about external threats. Ransomware has made a lot of headlines in the past couple of years. Fortunately, we limit our exposure by keeping email off of our operational network and relegate that to the business network. In addition to external threats, we’re also concerned about insider issues. Whether it’s intentional, like somebody doing something they shouldn’t do, or human error, which of course is unintentional. You can have accidental consequences that can cause problems, too. So, we try to look at all those scenarios.
Q: What are the biggest challenges you see in terms of monitoring for those type of threats and detecting them?
SW: Clearly, it’s visibility. We’ve tried to increase our ability to monitor and that is one of the reasons we implemented a security product from a vendor called Indegy to be able to better monitor our network. We evaluated a number of tools, and one of the things that we like most about their technology is the active monitoring capability that allows us to actually query PLCs and see if changes have been made to them. Since changes can be made in a variety of different ways (over the network, directly on a device, etc.), in some cases they can be hard to detect. But if you query the PLC, then you can see if the code on that PLC has changed. The ability to not just monitor network traffic but also discover and inventory our devices, knowing all the systems and equipment that are on the network, was very important to us.
Q: What advice would you give your peers in the industry that are struggling with the same problem?
SW: The first thing I did when I started with the city was gather a detailed inventory of what systems were part of the network. This was initially done by just going out and putting hands on the systems. But with some of the automated tools that are available now a lot of that can be done in a matter of seconds by pulling information that’s available on the network. For example, you can find out what version of Windows you have, firmware levels on PLCs and other information. It’s a lot easier than going out to every system and figuring out what firmware level you might have on a PLC.