Database giant Oracle Corp. said Monday that it will pay $2.1 billion to acquire Acme Packet Inc . of Bedford, which makes devices that connect Internet-based communication networks to one another and to traditional phone systems.

Oracle will pay $29.25 a share in cash, 22 percent higher than Acme Packet’s closing stock price on Friday. Taking Acme Packet’s cash holdings into account, Oracle will pay a net price of about $1.7 billion. It’s the biggest purchase of a Massachusetts technology company since May of 2011, when Applied Materials Inc., a California manufacturer of chipmaking gear, bought Varian Semiconductor Equipment Associates Inc. of Gloucester for $4.9 billion.