F5 Networks has bought firewall developer MagniFire Websystems for $29 million in cash, F5 has announced.

The company will add MagniFire's TrafficShield security appliance to its Application Traffic Management architecture, allowing companies to spot attacks on Web-based applications, it said.

TrafficShield is a rack-mounted security appliance that scans incoming HTTP traffic for evidence of attacks or suspicious activity. The product can spot a long list of potential threats to Web-based applications and services, including denial-of-service attacks, buffer overflows and invalid user inputs, according to MagniFire.

That focus meshes well with F5's existing products, including its BIG-IP line of appliances, which manages and directs traffic to applications on LANs based on customer policies, network performance and availability to prevent service outages and overloads.

The acquisition therefore gives F5 ready-made technology for applying those same traffic management principles to the issue of application security, so companies can check legitimate traffic reaches Web applications and harmful traffic is weeded out.

The MagniFire purchase is not F5's first foray into the IT security space. In July 2003, it acquired SSL VPN company uRoam.

F5 has also announced a new version of its FirePass Controller which now supports the Mac and Linux operating systems. It is not alone in focusing resources on security. Leading competitors in the network equipment space, including Cisco and Juniper, are devoting more resources to building and acquiring security products.

In February, Juniper acquired firewall and VPN maker NetScreen for $4 billion.

And at the recent Networld+Interop 2004 show in Las Vegas, Cisco head John Chambers spoke of how security needs to be built into networking architectures, allowing users to access software applications from wherever they are.