Motorola used to be one of those giant corporate conglomerates that employed 150,000 people, many at a massive campus in Schaumburg, Illinois. But it hit hard times, and over the last several years it sold off chunks of itself and became Motorola Solutions.

Motorola Solutions is still a huge company. It employs around 14,000 and generated $5.8 billion in revenue over the last four quarters. But it has sold the huge campus and moved to new headquarters in Chicago.

As part of its move and cost cutting, Motorola is unplugging its data centers and going all-in in the cloud.

Its cloud of choice is Amazon Web Services, Leo Wang, head of cloud computing, told Business Insider.

"When we first we started, we were moving just one data center, our Schaumburg data center," he said. "Within 6 to 7 months, we moved more than 200 servers, and 150 applications, and we had more than $2 million in computer yearly spend moved over to AWS."

And they liked AWS so much, they decided to move everything else into it, worldwide, over the course of the next two years, Wang said. As of today, the company has moved about 450 servers to AWS, he added.

"We save millions per year. We invested millions initially but the long range savings will be significant, and we have a more aggressive plan next year and the year after."

Choosing Amazon wasn't automatic. In fact, Motorola already had a smaller contract with Microsoft to use its competing cloud, Azure. But Microsoft wasn't able to turn that into a bigger sale.

Why Microsoft didn't win

Microsoft CEO Satya Nadella Business Insider Motorola Solutions sells radios and communications equipment to government agencies like police, fire, other emergency services.

They chose Azure because Azure had a crucial government security certification known as Criminal Justice Information Services (CJIS) and Amazon didn't.

So when Motorola opted to move everything to the cloud, the IT folks looked at Amazon, Microsoft, and Google.

"Amazon had better technologies in almost all areas. It is much more mature in terms of functionality. They excelled in every aspect that we needed from the cloud perspective and from the customer service perspective, but they didn’t have the CIJS compliance," Wang said.

But CIJS certification was a deal breaker, they told Amazon.

"Initially, they were hesitating. They were not interested in having this certification because they were so big in the market," Wang says.

But they agreed to look into it and decided to get CIJS, realizing it could open up new government markets for its cloud. Amazon is already making a name for itself pursuing government cloud business with its "GovCloud," a highly secured section of the AWS's services reserved for government use.

"Once they realized the importance of this certification in this industry, they invested. In a few months they were certified, and they created a Gov Cloud for us," Wang said.

Motorola Solutions head of cloud computing Leo Wang Leo Wang By doing this, Motorola was able to launch a brand new app for its law enforcement customers on AWS that lets them store camera footage on AWS. This app has the potential to be huge for Motorola and AWS, Wang believes.

AWS isn't known for its customer service, but Wang can't sing AWS's support praises any louder.

"Andy Jassy personally came to our office and had a detailed look at what we had. They put a lot of attention to us," Wang said.

In comparing AWS's support to that from Microsoft, he called it "very different," saying, "With AWS we are very tightly engaged with them in almost all efforts. We have meetings, we share our concerns, we have follow up, and a consultant works closely with us, and works closely with the product team."

Amazon's big gotcha

There is one big downside to choosing Amazon: it's harder to keep track of costs.

Like all cloud providers Amazon charges for the actual time each machine (known as an instance) is used. That's a benefit over buying servers, which a company pays for if they use them or not.

AWS CEO Andy Jassy WSJ D.Live/screen capture But if a company is not carefully watching its Amazon usage, it could run up a huge bill.

"In the cloud, it’s so easy to create resources, but the right governance over the usage is needed for you to get the price benefits. You need to be able to start and stop that instance only when the app is running." Wang said. "If you simply spin up the servers without proper governance, you could end up paying more."

AWS doesn't make this task easy.

"AWS, their pricing model is very complicated, that is a drawback," Wang says. He has complained to AWS about it and believes "they are improving in that area."

There are hoards of apps that will monitor Amazon usage. Motorola doesn't use them. Instead, it hired a cloud consultant, 2nd Watch, to help it move to AWS, size everything properly, train the IT staff and set up its own internal systems for watching usage, Wang says.

Downsizing Oracle

Larry Ellison Business Insider One bonus for moving to the cloud is that Motorola has a chance to look at its big expensive apps, like Oracle's database, and ditch them.

"In some of the instances, if we can use AWS [databases] instead of Oracle, we are doing that," he said, though he's not ready to dump Oracle completely. "Oracle is still our big partner."

This is a huge concern for Oracle these days, as Amazon rolls out more database alternatives and has created a tool that helps a company move its database from Oracle to Amazon's homegrown one.

Avoiding hard feelings

Motorola Solutions Chicago cloud team Leo Wang One last thing Motorola needed to work on was getting the IT staff on board. No one lost their jobs because of this move, Wang says. That's because Motorola had an outsourcer called CSC managing its infrastructure. With AWS, it won't need CSC.

But there's still some jealousy among the staff.

"My team is very excited because they are the core cloud computing team, doing the work. Some other IT teams are feeling left out. I can sense that kind of feeling," he said.

So, Wang says, he's working on eventually getting the other IT folks trained on the cloud. And people are excited to learn all the latest, greatest cloud tech. It's good for their careers. "I will help them and they will help me, too."