AT&T Inc. (NYSE: T) today unveiled a new cloud-based security service, teaming with McAfee Inc. (NYSE: MFE) to provide email security for enterprises.

The AT&T Secure E-mail Gateway Service will check inbound messages to detect spam, malicious attachments, or embedded URL-based attacks and connections from spammers or computers that have been taken over by botnets, and stop those messages before they even hit the enterprise network. The service also checks outgoing messages against company policies to protect corporate data and intellectual property.

McAfee is providing its global threat intelligence technology, which is being incorporated into the AT&T gateway.

As network threats grow in size and complexity, network-based security as a service becomes more appealing because this approach isolates threats before they hit the corporate LAN, and because the constant updating required to on top of threats is done by the service provider.

Managed security services are also becoming more competitive, with multiple service providers unveiling new options. AT&T already provides virtualized firewall, intrusion detection and prevention, URL filtering, content filtering, and protection against distributed denial-of-service attacks, but may find itself chasing Verizon Enterprise Solutions , which has leveraged its acquisition of CyberTrust to build a portfolio of network-based security options that has significantly expanded of late. (See Verizon, Novell Offer ID Management for Clouds and Verizon Scales Security for SMBs.)

— Carol Wilson, Chief Editor, Events, Light Reading