On 4 January 2007, Cisco announced a definitive agreement to acquire IronPort Systems, a provider of enterprise messaging security products.
The IronPort acquisition will allow Cisco to move into the fast-growing e-mail security market, which is currently valued at approximately $850 million and growing at a rate of approximately 40% annually. The key technology value that Cisco will receive is a strategic foundation on which to begin building a security infrastructure for unified communications, including e-mail.
Gartner Analysis : The consolidation in the e-mail security market is now almost complete. Other vendors will find it difficult to compete with industry leaders Cisco, Microsoft and Symantec in the enterprise market. IBM and (potentially) Juniper Networks are the only other major vendors that have a strategic interest in this market, though BorderWare and Proofpoint remain as respected independent players. Gartner believes the two remaining service providers, MessageLabs and Postini, will likely be acquired by telecom providers in their respective markets.
Extracted from Gartner - IronPort Buy Will Make Cisco a Major E-Mail Security Player