Juniper Networks Monday announced it has acquired Altor Networks, a provider of virtualization security for data centers, for $95 million.Juniper said the acquisition will allow it to offer an integrated, scalable security architecture for data centers that is designed to protect physical and virtual systems. Juniper and Altor had an existing partnership and Juniper invested in the company through its Junos Innovation Fund.Also see: Top tech M&A deals of 2010Security in virtualized data centers is a hot market with workloads and resources moving throughout and between data centers and cloud computing environments. Indeed, Cisco Chairman and CEO John Chambers called cloud security a \u201cnightmare.\u201dCisco has been making virtualization and cloud security a staple of its overall strategy, and earlier this year invested in security start-up HyTrust. \u00a0Cisco also just acquired LineSider to help tame the cloud and virtualization security beast. And EMC, Intel and VMware announced a partnership to secure private clouds, which rely heavily on virtualization. \u00a0Altor was founded in 2007 and announced its first product in March 2008, promising to provide visibility into data traffic between virtual machines (VM). Altor VF, the company's virtual firewall, was made available in October 2008. It is one of several products using VMware's VMsafe API, which opens the company's hypervisor to security vendors.Altor VF is designed to stop malware outbreaks in VMs and attacks on the hypervisor, prevent workloads with different security requirements from being mixed on the same host server, and comply with auditing requirements by monitoring, reporting on and filtering virtual network traffic.Altor's products are designed to enable security visibility, compliance and control over the VM infrastructure so operators can understand the applications, services and traffic being sent between VMs.The company\u2019s customers include those in the federal, state and local government, service provider, university and retail verticals.Read more about data center in Network World's Data Center section.