Rumours of a potential deal with HP, IBM or Oracle have pushed ArcSight's share value up 70% in recent weeks, according to US reports.
The deal is the latest in a series of acquisitions aimed at broadening HP's services offerings and expanding into new areas to compete with rivals following a similar strategy.
The ArcSight deal comes just weeks after HP won a bidding war with Dell to acquire storage firm 3Par for $2.4bn.
ArcSight and 3Par fit well in HP's growing enterprise services division, where profit margins are higher than in PC sales, analysts said.
HP plans to integrate ArcSight's Enterprise Threat and Risk Management Platform across its application development and operations management solutions.
"In a world where perimeter security is no longer enough, businesses need this holistic approach to secure their networks, applications, and sensitive data", said Tom Reilly, ArcSight's chief executive and president.
HP competitors Cisco Systems and IBM have made similar acquisitions in security to integrate them into services since security is increasingly considered a critical part of the decision-making process when ordering other goods or services.
This story was first published by Computer Weekly