the overall write performance of flash memory. In order to solve this "erase-before-write" problem, the flash memory controller can be integrated with a software module, called "flash translation layer (FTL)." Among many FTL schemes available, the log block buffer scheme is considered to be optimum. With this scheme, a small number of log blocks, a kind of write buffer, can improve the performance of write operations by reducing the number of erase operations. However, this scheme can suffer from low space utilization of log blocks. In this paper, we show that there is much room for performance improvement in the log buffer block scheme, and propose an enhanced log block buffer scheme, called FAST (full associative sector translation). Our FAST scheme improves the space utilization of log blocks using fully-associative sector translations for the log block sectors. We also show empirically that our FAST scheme outperforms the pure log block buffer scheme. . 2007. A log bufferbased flash translation layer using fully-associative sector translation. ACM Trans. Embedd.

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The semantics of online authentication in the web are rather straightforward: if Alice has a certificate binding Bob's name to a public key, and if a remote entity can prove knowledge of Bob's private key, then (barring key compromise) that remote entity must be Bob. However, in reality, many websites-and the majority of the most popular ones-are hosted at least in part by third parties such as Content Delivery Networks (CDNs) or web hosting providers. Put simply: administrators of websites who deal with (extremely) sensitive user data are giving their private keys to third parties. Importantly, this sharing of keys is undetectable by most users, and widely unknown even among researchers. In this paper, we perform a large-scale measurement study of key sharing in today's web. We analyze the prevalence with which websites trust third-party hosting providers with their secret keys, as well as the impact that this trust has on responsible key management practices, such as revocation. Our results reveal that key sharing is extremely common, with a small handful of hosting providers having keys from the majority of the most popular websites. We also find that hosting providers often manage their customers' keys, and that they tend to react more slowly yet more thoroughly to compromised or potentially compromised keys.

Abstract. Recently, flash memory is widely adopted in embedded applications since it has several strong points: non-volatility, fast access speed, shock resistance, and low power consumption. However, due to its hardware characteristic, namely "erase before write", it requires a software layer called FTL (Flash Translation Layer). This paper surveys the state-of-the-art FTL software for flash memory. This paper also describes problem definitions, several algorithms proposed to solve them, and related research issues. In addition, this paper provides performance results based on our implementation of each of FTL algorithms.

Immunohistochemical localization of the injury specific apolipoprotein, acute phase serum amyloid A (A-apoSAA), was compared in brains of patients with neuropathologically confirmed Alzheimer's disease (AD), multiple sclerosis (MS), Parkinson's disease (PD); Pick's disease (Pick's), dementia with Lewy bodies (DLB), coronary artery disease (CAD), and schizophrenia. Affected regions of both AD and MS brains showed intense staining for A-apoSAA in comparison to an unaffected region and non-AD/MS brains. The major site of A-apoSAA staining in both diseases was the myelin sheaths of axons in layers V and VI of affected cortex. A-apoSAA contains a cholesterol binding site near its amino terminus and is likely to have a high affinity for cholesterol-rich myelin. These findings, along with our recent evidence that A-apoSAA can inhibit lipid synthesis in vascular smooth muscle cells suggest that A-apoSAA plays a role in the neuronal loss and white matter damage occurring in AD and MS.

The Domain Name System (DNS) provides a scalable, flexible name resolution service. Unfortunately, its unauthenticated architecture has become the basis for many security attacks. To address this, DNS Security Extensions (DNSSEC) were introduced in 1997. DNSSEC's deployment requires support from the top-level domain (TLD) registries and registrars, as well as participation by the organization that serves as the DNS operator. Unfortunately, DNSSEC has seen poor deployment thus far: despite being proposed nearly two decades ago, only 1% of .com, .net, and .org domains are properly signed.In this paper, we investigate the underlying reasons why DNSSEC adoption has been remarkably slow. We focus on registrars, as most TLD registries already support DNSSEC and registrars often serve as DNS operators for their customers. Our study uses large-scale, longitudinal DNS measurements to study DNSSEC adoption, coupled with experiences collected by trying to deploy DNSSEC on domains we purchased from leading domain name registrars and resellers. Overall, we find that a select few registrars are responsible for the (small) DNSSEC deployment today, and that many leading registrars do not support DNSSEC at all, or require customers to take cumbersome steps to deploy DNSSEC. Further frustrating deployment, many of the mechanisms for conveying DNSSEC information to registrars are error-prone or present security vulnerabilities. Finally, we find that using DNSSEC with third-party DNS operators such as Cloudflare requires the domain owner to take a number of steps that 40% of domain owners do not complete. Having identified several operational challenges for full DNSSEC deployment, we make recommendations to improve adoption.

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