Best practices in mobile data communications

     The Orange County Sheriff's Department (OCSD) covers an expansive geographic area that includes the communities of San Clemente, Aliso Viejo, Dana Point, Orange, Rancho Santa Margarita, Santiago Canyon, Stanton, Lake Forest and Laguna Hills. The varied terrain and large area that our deputies patrol posed a number of obstacles when we began to implement a true mobile data communications strategy seven years ago.

     Since then, we've been piecing together a wireless data solution that has maximized the efficiency of our mobile workers by better using the available cellular data networks and county-owned Wi-Fi hotspots. We've found ways to let our deputies perform their jobs with greater flexibility and productivity.

     What we learned from the process may help other departments with their own roll-outs or with implementing enhancements to their existing mobile deployment systems.


     Today, the OCSD has two distinct groups of mobile data users: investigators and patrolling officers. Both groups are highly mobile and spend most of their workdays in their vehicles. The investigators and patrol officers are equipped with laptops fitted with Wi-Fi and cellular modem cards. When they are near an OCSD Wi-Fi hotspot, these personnel use a Wi-Fi card to connect to the Internet at high speed. From the field, they'll connect to the cellular data network.

     Both groups of users access similar networked resources in order to do their jobs. The investigators mainly need wireless access for e-mail, Intranet, shared folders on OCSD servers, and the California Law Enforcement Telecommunications System (CLETS).

     In addition to these applications, patrol officers also rely on our computer-aided dispatch (CAD) and mapping applications.

     To put a truly mobile solution in place, we looked for a variety of ways to maximize the efficiency of the high-speed broadband solution used across the county. Both investigators and officers need to have always-on access to numerous network resources and state and federal databases from wherever they might be. So our goal was to create a way for patrolling officers and investigators to have seamless and secure access to multiple data networks, key applications and criminal databases.

     Upon deployment of laptops and data cards, we found that our officers and investigators were not able to take full advantage of our mobile solution. Computer applications were crashing when wireless network connections were lost, which was common given the diverse geography of Orange County. Data was lost when these network connections were reset. Most importantly, our officers were having to focus on managing network configurations and connections, not law enforcement and public safety. We needed to make sure that our technology did not require our officers to become IT experts, because they have far more important work to do than troubleshooting their laptops.

     We found that Orange County's mobile challenges could be distilled down to a few key issues that most state and local government deployments must address: wireless coverage gaps and interruptions, lack of roaming capabilities, and concerns over security.

     • Wireless coverage gaps and interruptions

     We've all experienced the frustration of a dropped cell-phone call. The issues are far more problematic when it's a wireless data application on a laptop. As the OCSD investigators and officers traveled across the county, they would pass in and out of wireless coverage areas — driving through a tunnel, into a parking garage or just traveling in an area of the county which had limited cellular coverage. When officers entered one of these areas, they'd lose their network connections and applications would lose their connections to back-end servers. The applications would then lock up, which required them to be restarted.

     Restarting takes time; it requires re-logging onto the network and retyping any work in progress. In our case, application stability issues dramatically impacted the productivity of OCSD's mobile users by causing frustration and requiring our IT support team to field numerous calls from complaining officers telling us that they could not get connected or that their applications were not working.

     • Wireless roaming and rollover

     With the proliferation of OCSD Wi-Fi networks across the county, we wanted to make sure that officers had the ability to connect with them to log onto domain accounts, to send and receive large files, upload reports, or receive software updates.

     However, managing multiple network connections would have been a manual process. With officers having to manage the switch between Wi-Fi and cellular data themselves, productivity was reduced and their focus was placed where we didn't want it — on their laptops as opposed to their primary public safety duties.

     Our officers needed us to find a way to have this switch be automatic without their intervention. We also wanted to find a way to have this transition occur automatically to whichever was the fastest available network.

     • Data security

     End-to-end data security was also paramount in our wireless plan. OCSD's investigators and patrol officers spend most of the day on the road connecting via wireless networks to local and state databases containing sensitive personal information. This meant that they needed to ensure data transmissions were secure. With federal security standards such as FIPS 140-2 as well as potential California Justice Information System (CJIS) standards for data security on the horizon, we wanted to ensure that we were protected and that we were planning ahead for future requirements.

Mobile solution best practices

     In the case of OCSD, we found the best option to solve our wireless and connectivity challenges was to install specialized mobile virtual private network (VPN) software on our officers' laptops and our back-end servers.

     In our case, we chose Mobility XE Mobile VPN software from NetMotion Wireless because its solution is widely used by hundreds of law enforcement and public safety agencies around the country. With this software, if an officer's laptop should lose wireless network connectivity, the mobile VPN server software manages and maintains the applications and connections on the back end, with the client software holding the applications in place on the device until a network connection can be restored. Once restored, the client and server software resume the application sessions.

     • Handling coverage gaps and interruptions

     Once we implemented, the issue of stability for both applications and connections was resolved. We were able to manage the connections between applications and networks, and to shield applications from lost coverage or interference that would otherwise cause them to crash.

     The result is that the software essentially "tricks" the computer applications into thinking that the network connection is fine — no matter what the condition of the connection — and so prevents computer crashes and other issues that arose without the software.

     It worked as planned: Once the mobile user returned to a good wireless coverage area, his or her applications restarted exactly where they left had off. Our officers did not have to spend time reconfiguring or modifying anything on their laptops. In fact, from the users' perspective, the sporadic losses of coverage that did occur were nearly imperceptible, because our mobile VPN managed and resumed the connections seamlessly behind the scenes.

     • Addressing the need for wireless roaming and rollover

     Due to the mobile VPN's client and server design, applications moved seamlessly from one connection type to another. So OCSD was able to present its investigators and officers with a seamless roaming solution. As users approach OCSD hot spots, the software senses the higher-speed network availability and automatically moves the users' applications to the faster network. During times when only the wide-area network is available, the mobile VPN optimizes and compresses the data transmission so OCSD's investigators and patrol officers will see considerably faster data transmission times across the networks.

     • Providing end-to-end security

     The mobile VPN also provided complete end-to-end security using FIPS 140-2 validated AES encryption, whereby all wireless data was transmitted through a secure VPN tunnel.

Crafting a mobile strategy

     When implementing your wireless strategy, carefully consider the use case scenarios and anticipate the common problems with these deployments. Most importantly, your mobile strategy should not rely on manual intervention and should account for the availability of multiple networks.

     With reliable and seamless access, our investigators today are able to perform critical tasks such as real-time justice system queries into criminal history — anywhere and anytime they need. They are also able to communicate quickly with judges, obtain an arrest or search warrant, or request backup support from other sheriff's personnel while monitoring the site of suspected criminal activity.

     With a proper mobile VPN solution in place, we've now maximized the efficiency of our wide-area network and created seamless mobility.

     Ed Lee is project manager, information systems for the Orange County Sheriff's Department, which is headquartered in Santa Ana, California.