Blue Coat Systems, a Sunnyvale, Calif.-based web security and wide area network (WAN) optimization provider, has acquired Crossbeam Systems, maker of a platform that helps companies manage and consolidate their third-party security offerings. The deal, expected to close Dec. 31 for an undisclosed amount, will allow Blue Coat to expand its security and networking solutions offerings. Crossbeam, headquartered in Boxborough, Mass., has offices in Europe, Latin America and Asia Pacific. In February, Chicago private equity firm Thoma Bravo acquired Blue Coat for $1.3 billion.