Blue Coat Systems has agreed to acquire rival WAN optimisation vendor Packeteer for $268m (£135.1m).

Both companies are focused on technologies that improve the performance of applications delivered over a wide area network. Blue Coat has hitherto focused on content filtering, web cache and proxy server appliances, and is looking for the Packeteer acquisition to strengthen its traffic shaping capabilities.

Packeteer also has over 10,000 customers worldwide and an installed base of over 50,000 units.

“The acquisition of Packeteer will enable us to extend our leadership in solving branch office application performance challenges and addressing security threats," said Brian NeSmith, chief executive of Blue Coat in a statement.

Packeteer had recently rejected a bid from a private equity group worth $200m.

The deal is expected to close in the second quarter of 2008, subject to regulatory approval.