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X.509 certificates underpin the security of the Internet economy, notably secure web servers, and they need to be revoked promptly and reliably once they are compromised. The original revocation method specified in the X.509 standard, to distribute certificate revocation lists (CRLs), is both old and untrustworthy. CRLs are susceptible to attacks such as Man-in-the-Middle and Denial of Service. The newer Online Certificate Status Protocol (OCSP) and OCSP-stapling approaches have well-known drawbacks as well. The primary contribution of this paper is Secure Revocation as a Peer Service (SCRaaPS). SCRaaPS is an alternative, reliable way to support X.509 certificate revocation via the Scrybe secure provenance system. The blockchain support of Scrybe enables the creation of a durable, reliable revocation service that can withstand Denial-of-Service attacks and ensures non-repudiation of certificates revoked. We provide cross-CA-revocation information and address the additional problem of intermediate-certificate revocation with the knock-on effects on certificates derived thereof. A Cuckoo filter provides quick, communication-free testing by servers and browsers against our current revocation list (with no false negatives). A further contribution of this work is that the revocation service can fit in as a drop-in replacement for OCSP-stapling with superior performance and coverage both for servers and browsers. Potential revocation indicated by our Cuckoo filter is backed up by rigorous service query to eliminate false positives. Cuckoo filter parameters are also stored in our blockchain to provide open access to this algorithmic option for detection. We describe the advantages of using a blockchain-based system and, in particular, the approach to distributed ledger technology and lightweight mining enabled by Scrybe, which was designed with secure provenance in mind. 

As data-intensive science becomes the norm in many fields of science, high-performance data transfer is rapidly becoming a core scientific infrastructure requirement. To meet such a requirement, there has been a rapid growth across university campus to deploy Science DMZs. However, it is challenging to efficiently monitor the traffic in Science DMZ because traditional intrusion detection systems (IDSes) are equipped with deep packet inspection (DPI), which is resource-consuming. We propose to develop a lightweight side-channel based anomaly detection system for traffic winnowing to reduce the volume of traffic finally monitored by the IDS. We evaluate our approach based on the experiments in a Science DMZ environment. Our evaluation demonstrates that our approach can significantly reduce the resource usage in traffic monitoring for Science DMZ.