SGXTuner: Performance Enhancement of Intel SGX Applications via Stochastic Optimization

Intel SGX has started to be widely adopted. Cloud providers (Microsoft Azure, IBM Cloud, Alibaba Cloud) are offering new solutions, implementing data-in-use protection via SGX. A major challenge faced by both academia and industry is providing transparent SGX support to legacy applications. The approach with the highest consensus is linking the target software with SGX-extended libc libraries. Unfortunately, the increased security entails a dramatic performance penalty, which is mainly due to the intrinsic overhead of context switches, and the limited size of protected memory. Performance optimization is non-trivial since it depends on key parameters whose manual tuning is a very long process. We present the architecture of an automated tool, called SGXTuner, which is able to find the best setting of SGX-extended libc library parameters, by iteratively adjusting such parameters based on continuous monitoring of performance data. The tool is to a large extent algorithm agnostic. We decided to base the current implementation on a particular type of stochastic optimization algorithm, specifically Simulated Annealing. A massive experimental campaign was conducted on a relevant case study. Three client-server applications Memcached, Redis, and Apache were compiled with SCONE's sgx-musl and tuned for best performance. Results demonstrate the effectiveness of SGXTuner

Due Process in Antitrust Enforcement: Normative and Comparative Perspectives

Due process in antitrust enforcement has significant implications for better professional and accurate enforcement decisions. Not only can due process spur economic growth, raise government credibility, and limit the abuse of powers according to law, it also promotes competitive reforms in monopolized sectors and curbs corruption. Jurisdictions learn from the best practices in the investigation process, decisionmaking process, and the announcement and judicial review of antitrust enforcement decisions. By comparing the enforcement policies of China, the European Union, and the United States, this article calls for better disclosure of evidence, participation of legal counsel, and protection of the procedural and substantive rights of the respondent in the investigation process. In conducting evidence review and arriving at punitive decisions, the enforcement agency should establish a separation between investigatory and adjudicatory functions. Finally, the issued punishment decision should contain more comprehensive information and be subject to judicial review

Correlation of Paraspinal Atrophy and Denervation in Back Pain and Spinal Stenosis Relative to Asymptomatic Controls

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/146797/1/pmr239.pd

SecureKeeper: confidential zooKeeper using intel SGX

Cloud computing, while ubiquitous, still suffers from trust issues, especially for applications managing sensitive data. Third-party coordination services such as ZooKeeper and Consul are fundamental building blocks for cloud applications, but are exposed to potentially sensitive application data. Recently, hardware trust mechanisms such as Intel's Software Guard Extensions (SGX) offer trusted execution environments to shield application data from untrusted software, including the privileged Operating System (OS) and hypervisors. Such hardware support suggests new options for securing third-party coordination services. We describe SecureKeeper, an enhanced version of the ZooKeeper coordination service that uses SGX to preserve the confidentiality and basic integrity of ZooKeeper-managed data. SecureKeeper uses multiple small enclaves to ensure that (i) user-provided data in ZooKeeper is always kept encrypted while not residing inside an enclave, and (ii) essential processing steps that demand plaintext access can still be performed securely. SecureKeeper limits the required changes to the ZooKeeper code base and relies on Java's native code support for accessing enclaves. With an overhead of 11%, the performance of SecureKeeper with SGX is comparable to ZooKeeper with secure communication, while providing much stronger security guarantees with a minimal trusted code base of a few thousand lines of code

Does colon cancer ever metastasize to bone first? a temporal analysis of colorectal cancer progression

<p>Abstract</p> <p>Background</p> <p>It is well recognized that colorectal cancer does not frequently metastasize to bone. The aim of this retrospective study was to establish whether colorectal cancer ever bypasses other organs and metastasizes directly to bone and whether the presence of lung lesions is superior to liver as a better predictor of the likelihood and timing of bone metastasis.</p> <p>Methods</p> <p>We performed a retrospective analysis on patients with a clinical diagnosis of colon cancer referred for staging using whole-body ¹⁸F-FDG PET and CT or PET/CT. We combined PET and CT reports from 252 individuals with information concerning patient history, other imaging modalities, and treatments to analyze disease progression.</p> <p>Results</p> <p>No patient had isolated osseous metastasis at the time of diagnosis, and none developed isolated bone metastasis without other organ involvement during our survey period. It took significantly longer for colorectal cancer patients to develop metastasis to the lungs (23.3 months) or to bone (21.2 months) than to the liver (9.8 months). Conclusion: Metastasis only to bone without other organ involvement in colorectal cancer patients is extremely rare, perhaps more rare than we previously thought. Our findings suggest that resistant metastasis to the lungs predicts potential disease progression to bone in the colorectal cancer population better than liver metastasis does.</p

Dynamics of nanodroplets on topographically structured substrates

Mesoscopic hydrodynamic equations are solved to investigate the dynamics of nanodroplets positioned near a topographic step of the supporting substrate. Our results show that the dynamics depends on the characteristic length scales of the system given by the height of the step and the size of the nanodroplets as well as on the constituting substances of both the nanodroplets and the substrate. The lateral motion of nanodroplets far from the step can be described well in terms of a power law of the distance from the step. In general the direction of the motion depends on the details of the effective laterally varying intermolecular forces. But for nanodroplets positioned far from the step it is solely given by the sign of the Hamaker constant of the system. Moreover, our study reveals that the steps always act as a barrier for transporting liquid droplets from one side of the step to the other.Comment: 44 pages, 25 figure