Southeast Asia's largest telecommunications operator Singapore Telecommunications will acquire US-based cybersecurity firm Trustwave for US$810 million (A$1 billion) in an effort to expand itscloud-based services.

Trustwave will continue to operate as a stand-alone business unit, Singtel said. Its headquarters will remain in Chicago.
"It will leverage Singtel Group Enterprise's assets and market presence to broaden its overall security portfolio and address the fast growing emerging security market opportunity in the Asia Pacific region," Singtel said in a statement.
Singtel will buy a 98 percent equity stake in the company, while Trustwave's chairman and chief executive officer, Robert McCullen, will hold 2 percent.
Trustwave has over three million business subscribers, served by 1200 employees in 26 countries, and five global operations centres across Chicago, Denver, Minneapolis, Manila and Warsaw.
Its services include threat management, vulnerability management and compliance management.
Trustwave has net tangible liabilities of about US$84 million.
The transaction is subject to approval from regulatory authorities and other third parties, and is expected to be completed in three to six months.