Improving Confidentiality in Virtualized FPGAs

FPGAs are being deployed in modern datacenters to provide users with specialized accelerators that offer superior compute capability, increased energy efficiency, lower latency, and more programming flexibility than CPUs. However, FPGAs are not utilized as efficiently in datacenters: unlike CPUs, FPGAs in datacenters are currently not shared between users due to potential security risks. The higher flexibility that comes with FPGAs also gives more capabilities to malicious users. Several recent studies have demonstrated examples of FPGA user applications capable of remotely sniffing data from other applications running on the same FPGA. In this work, we look at various ways to ameliorate these threats by encrypting/decrypting the user application's data under different trust levels for current virtualized FPGAs. We also discuss the role of interconnect and discuss the potential of more efficient security features that can be implemented together with the interconnect if the FPGAs use a hard network on chip.