Security vendor Sophos has bought US network access control (NAC) specialist Endforce.

With this acquisition Sophos will come up against rival products from Cisco and Microsoft, which has integrated network access protection capabilities into its forthcoming Longhorn server product.

Infonetics Research analyst Jeff Wison said the NAC market is set to see rapid growth, with demand for network-integrated NAC appliances being particularly strong. Endforce's NAC products are software based, however, and are mainly targeted at larger enterprises.

Ovum analyst Graham Titterington said, "Endforce has one of the better [NAC solutions on the market] with regard to the flexibility of the policies that it can execute, and has recently won some high-profile customers."

Sophos said it will maintain Endforce's operation in Columbus, Ohio, and continue to develop and sell Endforce products under the Sophos brand.