US computer network giant Cisco Systems announced plans Tuesday to buy cybersecurity firm Sourcefire in a deal worth $2.7 billion. \"Sourcefire aligns well with Cisco\'s future vision for security and supports the key pillars of our security strategy,\" said Cisco vice president Hilton Romanski. \"Through our shared view of the critical role the network must play in cybersecurity and threat defense, we have a unique opportunity to deliver the most comprehensive approach to security in the market.\" Sourcefire specializes in \"continuous and pervasive advanced threat protection\" for all types of computing devices and in the Internet cloud. Cisco will pay $76 per share in cash for Sourcefire and assume outstanding equity awards for a total of $2.7 billion under the deal, which has been approved by the board of directors of each company. \"The notion of the \'perimeter\' no longer exists and today\'s sophisticated threats are able to circumvent traditional, disparate security products,\" said Cisco vice president for security Christopher Young. \"Organizations require continuous and pervasive advanced threat protection that addresses each phase of the attack continuum. With the acquisition of Sourcefire, we believe our customers will benefit from one of the industry\'s most comprehensive, integrated security solutions -- one that is simpler to deploy, and offers better security intelligence.\" Sourcefire, based in Columbia, Maryland, was founded in 2001 and went public in 2007. It has 650 employees and its 2012 revenues were $223 million.