The deal values Aruba at $24.67 share, including cash and debt. (Click here for the latest price.)
Both companies' boards of directors have approved the deal.
The purchase would be a boost for HP's wireless local area network market as more companies allow their employees to access work systems through wireless devices. Together the companies will deliver converged campus solutions and the new organization will be led by Aruba's Chief Executive Officer Dominic Orr.
The all-cash offer is a premium of 34.4 percent to Aruba's close on Feb. 24, the day before it was reported there was a deal in the works.
"Enterprises are facing a mobile-first world and are looking for solutions that help them transition legacy investments to the new style of IT," said HP CEO Meg Whitman said in a press release. "By combining Aruba's world-class wireless mobility solutions with HP's leading switching portfolio, HP will offer the simplest, most secure networking solutions to help enterprises easily deploy next-generation mobile networks."
The transaction is expected to close in the second half of HP's fiscal year 2015, subject to Aruba stockholder and U.S. regulatory approvals.
—Reuters contributed to this report.