When companies consider rolling out mobile-data applications, several issues always come up that strike fear in the hearts of CIOs, who don’t want to make major investments in an emerging technology that later proves to be unreliable, insecure or proprietary.

Read about 3G’s rising use across enterprises

Here’s a list of enterprises' five biggest concerns about Evolution Data Optimized (EV-DO) and other 3G technologies and what the telecommunications industry is doing to alleviate them.

Worry No. 1: Performance

What’s the point of buying high-speed wireless data services for your employees if the network doesn’t reach your branch offices or customers? That’s why one of the first questions that network executives ask is about coverage and speed.

"If you have great speed but you’re in four markets, then enterprises don’t want that," says Tim Donahue, vice president of business marketing for Sprint Nextel. "They want ubiquity. At 80% of the U.S. population, you are definitely there. Then you can add on the remaining locations. Enterprises want to know that wherever they are, you are there."

Wireless access has to be not only available and fast but also reliable -- not necessarily the 99.999% reliability that companies have come to expect from traditional wired networks, but reliable enough for their applications.

"We’ve seen more emphasis on reliability for business users in the last six to 12 months," says Mike O’Malley, director of external marketing at Tellabs, which sells wireless data equipment to carriers. "This really raises the stakes for the carriers. They have to make sure they have coverage -- not just in any building but in the canyons of LaSalle Street. They need to make sure that the call is not going to be dropped because it’s being used for very important, time-sensitive information and financial transactions."

Carriers say the best way for companies to determine whether a wireless data service performs well enough for their applications is to test it. "We tell CIOs to trial EV-DO for 30 to 60 days and then make a determination," Donahue says.

Wireless network performance is becoming more important to enterprise customers as they move beyond e-mail to more critical business applications such as real-time ordering and inventory management.

CIOs care about "the level of service that the mobile operator can provide in resolving potential issues that will arise in terms of application performance delivery," says Jim Vale, product manager at Network General, which sells sniffers and other network management devices to wireless carriers to help them isolate problems on their networks. "As data is pushed out to the mobile service offering, the enterprise really has very little or no visibility into that last mile. And it’s a very long mile."