So at the Mobile World Congress on Monday, the two companies announced a partnership that they say will help Ericsson’s (ERIC) traditional customers—telcos and service providers—get up to speed on cloud computing services using Amazon (AMZN) infrastructure. And it will help those service providers build gateways linking their own data centers to AWS data storage. Another goal is to build technology that manages workflow between telcos’ internal facilities and AWS data centers.

The appeal of public cloud computing is that businesses can rent computing power, storage space, and networking capacity from a cloud provider that owns and maintains those resources in its own data centers. The benefit to customers is that they pay only for what they use and don’t have to worry about updating all that hardware and software on the back end. But one hurdle thus far is that older data centers built to run traditional business workloads are not as well suited to the cloud as the massive-scale data centers built by Amazon Web Services or Microsoft for cloud computing.

How Americans use mobile apps.

Traditional telcos like Verizon (VZ) and CenturyLink (CTL) have ventured into cloud computing but have struggled for traction while AWS has built what looks to be a $10 billion a year cloud business.

Update: One reason is that telcos are used to a slower development model than cloud providers, whose claim to fame is their ability to churn out new features and capabilities seemingly every day. And that is why telcos are clamoring about the software-defined data center game plan espoused by Facebook and other new-era tech players. If data center gear can be updated and reconfigured in software, there is less need for forklift hardware upgrades that are time-consuming and costly.

Nokia, for example, is aboard Facebook’s just-announced Telecom Infra Project, described here. Neither Ericsson or Amazon is part of that effort.

Ericsson’s expertise in industrial-grade networking gear and mobile communications and Amazon’s cloud computing smarts are a winning combination, Jason Hoffman, head of Ericsson’s Cloud business told Fortune.

“The mobile edge is what we do and on the other end are the mobile apps and the Internet of things apps and those developers are on Amazon. Both companies would like it if all that infrastructure worked really well together,” he said.

Ericsson’s technology can ensure that graphics-rich games or video get delivered fast and reliably over wireless connections, something that mobile developers care very much about—especially in remote areas where wire-line connections are sparse.

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Plans call for Ericsson to set up “cloud innovation centers” to bring its customers up to speed about cloud computing. The first such facility, set up with Australian teleco Telestra, is already under way. Ericsson will contribute engineers and consultants while Amazon will chip in solution architects, training, and professional services.

In other Ericsson news, the company joined the Open Compute Project, a consortium of tech companies that is specifying new, open-source designs for servers and other data center hardware. Initially launched by Facebook in 2011, OCP has gained many members in the interim—Verizon and AT&T joined last month. Ericsson also inked a deal with Quanta, the big Taiwanese hardware maker, to collaborate on next-generation data center hardware.

Former CenturyLink Cloud Guru Lands at Ericsson.

On the competitive front, Ericsson, which vies with Huawei and Alcatel-Lucent (now finalizing its merger with Nokia) in telcom network infrastructure, needs to offer its customers the best way to the cloud. And AWS wants to keep developers, especially mobile developers, focused on its infrastructure and not that of public cloud rivals Google (GOOG) or Microsoft (MSFT).

Note: This story was updated at 7:49 a.m. EST with reference to Facebook’s TIP project.