Open, elastic provisioning of hardware acceleration in NFV environments Network Functions Virtualization (NFV) is a new paradigm to move network tasks currently running on dedicated, vendor-specific hardware to elastic, virtualized environments, similar to IaaS cloud computing. A major challenge of NFV is to reach the performance known from dedicated hardwareappliances, which often leverage ASIC, FPGA or NPU-based hardware acceleration to increase throughput and reduce delay. In this paper, a framework for elastic provisioning, programming and configuration of acceleration hardware for virtual network functions (VNFs) is proposed. Using this framework, VNFs can offload selected parts of their workload to heterogeneous acceleration processors, which may be shared among all VNF instances in the framework for improved resource utilization.