Monitoring The Nomads In Your Network

In discussing the dangers of the bring-your-own-device movement, Guy Levy-Yurista, chief technology officer of AirPatrol, points to a recent discussion with a private equity firm. It took three months for the firm to realize that an unknown device was logging into their network and collecting e-mail messages, he says.

The case underscores the need for better monitoring of devices in the network. Situational awareness is key to separating the wolves from the sheep in a massively mobile network, he says.

"The first step is to be able to understand all the devices that are logging into the network," he says. "Then, authentication, provisioning, and access control are the critical pieces to protecting the network."

While every company as a starting point should have locked down their wireless network, businesses need to do more now that more employee-owned devices are accessing potential sensitive parts of the company. At the very least, every mobile device should be secured by a passcode and be wiped if the user fails to enter in the correct PIN in 10 attempts, as a way to prevent lost and stolen device becoming a doorway into the company.

Yet there are additional steps a company can--and should--take as well.

1. Monitor the network
At the most basic level, companies can monitor the devices that connect to their network. Companies can track which devices connect to their internal systems, which means treating a phone no differently than a laptop, desktop, or server, says Tyler Lessard, chief marketing officer at Fixmo, a mobile-device security firm.

"You can allow any user to access the network, but then say, 'I'm going to watch what devices are coming in, and if any of them look like they are potentially malicious or bad, then I might go out and react to it,'" Lessard says.

This most basic level of monitoring has the benefit of being inexpensive. The necessary data could be culled from firewall logs, but companies would benefit from more tailored systems designed to alert in real time.

[With a growing mobile workforce, more employees using their personal devices for work, and closer relationships with partners, sensitive data continues to move outside of the corporate firewall. See Regaining Control Of Data In The Cloud.]

2. Monitor the user
Traveling further up the security food chain, companies can focus on both the users and the devices. Companies that do not allow their users to access sensitive data on their devices--limiting access, say, to ActiveSync's e-mail and calendar services--could potentially just register each device with a mobile-device management (MDM) system and assign each user a certificate to access the network.

Companies that want to control the devices, but not necessarily the applications on the devices, should require that each user register their device with the MDM software. While turning off access for all unregistered devices may work in theory, IT departments will be more successful using a carrot-and-stick approach: Giving each user, say, 30 days to register their devices before cutting them off, and granting additional benefits--such as VPN access or to users that finish the enrollment process, says Ahmed Datoo, vice product of product marketing at Citrix.

"So there is no way for them to get e-mail unless they enroll their device--that is the stick approach," Datoo says. "You give them a warning, and there is an amnesty period."

3. Control apps or use secure containers
When employees start gaining access to sensitive data with their devices, then the focus ceases to be on monitoring the actual devices and more about secure the data and keeping track of the applications that store the data.

Enterprise-managed app stores are one way to limit the access that users have to potentially malicious applications, but the use of secure, virtualized containers--representing separate spaces on the device that can be managed and deleted by the information-technology staff--can add more security.

"The problem is that the employee can download a file from Sharepoint--it's unstructured data, so [the company] doesn't know where it is--and if that person leaves the company, because it is their device, I'm not allowed to wipe it," Fixmo's Lessard says. "So when you start to go beyond e-mail, that's where you need to have additional software on the device to help control data."

Finally, when a user who is not fully trusted, such as a contractor, needs access data from a mobile device, companies can use virtual desktop infrastructure (VDI) to prevent the data from being uploaded to the device.

"That allows the user to have no data running on the device," says Citrix's Datoo. "You can allow the user to access sensitive data as well as legacy desktop apps on their iPhone and still know where the data is."

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