alization and managing the hardware's resources across the virtual functions (VFs) (Figure 10.4). Physical Appliance X.86 Server X.86 Server FIGURE 10.3 Service chains across WAN boundaries. Guest os Guest os Virtual HW Virtual HW Hypervisor Host os COTS HW FIGURE 10.4 Hardware virtualization. Building the Network of the Future Initially, there were many proprietary and open-source hypervisor options available in the mar- ket. Moreover, each network function provider supported a different set of hypervisors that created a problem for realizing the overall vision. Two key hypervisors considered for the analysis included VMWare and KVM. VMWare, a commercial product, provides a stable and feature-rich environment [2]. In addition, most of the virtual network functions providers already have support for VMWare-based virtual appliances. The strong industry focus on VMWare was mainly due to its prior installed base in the enterprise cloud environment and lack of a strong alternative platform for enterprise environments. One open-source alternative, KVM, which is also the default hypervisor for OpenStack, emerged as the only other viable alternative. It lacked the maturity of features that VMWare had but met the requirements associated with a smaller premise-based deployment. We believe that KVM provides several technical and nontechnical benefits that makes it a very good hypervisor choice for office branch (remote office) environment. The key reasons are listed below: For service providers, the branch platform is generally considered an extension of its net- work-based cloud platform. Since most service providers are relying on Open Source tech- nology such as OpenStack/KVM for their cloud initiatives, the ability to leverage the tooling for branch environments provides opportunities for significant cost benefits in future. The existing limitations of the KVM hypervisor were not applicable to a single server deployment in a branch environment. With the increased focus and adoption of Open Source initiatives, most vend