Cisco made repeated attempts to acquire IronPort Systems prior to finally stitching up the $782.3 million deal last week.

IronPort Australia Managing Director Michael Bosch said Cisco had been pursuing the gateway and email security firm for over two years because the purchase was key to Cisco's Network Access Control (NAC) offering.

"Cisco has used our technology for nearly four years and had made several offers to buy us; this purchase is part of its security strategy," he said.

Bosch believed the networking giant had such a huge footprint that most existing IronPort users would already be Cisco customers. Bosch confirmed IronPort would be run as a separate business unit inside Cisco for the next two years.

"Cisco has committed to running IronPort as a separate business unit, independent of the Cisco banner, for a minimum two-year term," he said.

The director of analyst firm, Hydrasight, Michael Warrilow, said it was likely IronPort had been an acquisition target for a number of vendors.

"Cisco is paying a premium for a high-performance solution which suggests that other vendors such as Symantec, may have been knocking on IronPort's door," Warrilow said.

He believed the acquisition, which is expected to close mid-year, would interrupt the partnership Cisco has already established with Microsoft. This means Microsoft users will be impacted, Warrilow added.

Last year both vendors announced a number of joint partnerships around policy enforcement and access control interoperability including the Network Access Protection (NAP) initiative.

"When you also consider Cisco's focus on unified communications, it will be interesting to watch what this means for Microsoft - particularly given the joint partnership on securing the enterprise network via initiatives such as NAC and NAP interoperability," Warrilow said.

"This investment is evidence that Cisco wants a piece of the security market - this time in the email and messaging arena."

It is unknown at this stage how many of IronPort's existing 408 employees will be integrated within Cisco.

Tom Gillis, IronPort vice president of marketing, said it is likely all staff will be retained.

A Cisco spokesperson confirmed IronPort's Chief Executive Officer Scott Weiss will report directly to Cisco Vice President and General Manager of the VPN and security unit, Richard Palmer. He said IronPort would be integrated into the security business unit of the Data Center, Switching and Security Technology Group (DSSTG).

"Cisco intends to retain virtually all members of the IronPort team and transition a limited number of employees to interim contractor roles where appropriate," the spokesperson said.