Ericsson announced Monday the acquisition of Vonage, a US cloud-based communications provider, in the Swedish company’s largest acquisition in recent memory as it expands its operations beyond its traditional telecommunications equipment business.

According to the company, the 6.2 billion (5.5 billion euros) deal is part of Ericsson’s strategy to expand its presence in wireless enterprise and broaden its global offerings.

Vonage’s board of directors unanimously approved the offer, according to the company.

Ericsson is one of the world’s largest telecom equipment manufacturers, competing with China’s Huawei and Finland’s Nokia in areas such as 5G networks.

The offer, at 21 dollars per share, represents a 28% premium over Vonage’s Friday closing price on the tech-heavy Nasdaq stock exchange.

Vonage, which was founded in 2001, provides IP voice telephony and has recently developed a cloud-based communications platform.

The company has 120,000 customers and provides one million developers with access to its API interface, which accounts for 80% of its $1.4 billion in annual sales.