Purewire, a provider of network security solutions, has closed on $2 million inn venture financing.

The startup, which was founded by a group of executives who once worked at security technology firm CipherTrust, also added Thomas Noonan to its board of directors. Noonan is former chairman and chief executive officer of Internet Security Systems, which was sold to IBM in 2006.

Purewire’s managers launched their new venture after Secure Computing Corporation acquired CipherTrust in 2006.

The $2 million round, led by Imlay Investments, boosts Purewire’s financing to $3.75 million.

The additional funding will be used to expand sales and marketing, product development and the company’s data centers.

“The security industry continues to thrive as businesses seek to protect employees and corporate assets from dangerous attacks,” Noonan said in a statement. “Web security, and particularly web security SaaS, is one of the hottest growth markets. That, combined with the team’s proven track record of delivering innovative offerings to protect enterprise customers, makes for a very promising opportunity.”

Purewire unveiled its Web Security Service product on Monday. It is available through a software as a service offering.