AT&T acquired VeriSign's security consulting unit for an undisclosed amount, and the telecommunications company said the deal will enable it to boost its network-based cybersecurity offerings for corporate customers.

VeriSign said the Global Security Consulting Services business worked with Fortune 500 companies to help them navigate regulations, understand corporate security requirements, identify vulnerabilities, meet industry compliance standards, and defend and respond to corporate attacks. AT&T will integrate the unit into its security team, and it is expected to augment the company's multi-layered network security offerings.

Enterprise security is becoming more complex as companies combine video, voice, and data onto a single network. The deal may help AT&T capitalize on this field, and research firm IDC estimates the annual market for U.S. IT security services is $11.7 billion, with the security consulting business alone being worth about $3.6 billion a year.

"The combined capabilities of VeriSign's security consulting business with AT&T's global reach, networking, and security portfolio will broaden our consulting and risk analysis expertise, and enable us to more quickly develop and bring to market capabilities to address the evolving security needs of businesses around the world," said Ron Spears, CEO of AT&T's business solutions unit, in a statement.

For VeriSign, the move is part of its larger strategy to sell off noncore assets in order to focus on markets like Internet infrastructure, online security, domain registry, and identity protection. The company sold its mobile messaging unit to Sinon Invest Holding earlier this year, and it sold its remaining shares of the mobile content company Jamba/Jamster to News Corp. for $200 million last October.

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