Ravish Khosla

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Cloud-computing systems are rapidly gaining momentum, providing flexible alternatives to many services. We study the Domain Name System (DNS) service, used to convert host names to IP addresses, which has historically been provided by a client's Internet Service Provider (ISP). With the advent of cloud-based DNS providers such as Google and OpenDNS, clients(More)
1389-1286/$ see front matter 2010 Elsevier B.V doi:10.1016/j.comnet.2010.10.005 ⇑ Corresponding author. Tel.: +1 (765) 325 7284 0739. E-mail addresses: ravish_03@yahoo.com (R. Kho edu (S. Fahmy), ychu@purdue.edu (Y.C. Hu), (J. Neville). The Border Gateway Protocol (BGP) maintains inter-domain routing information by announcing and withdrawing IP prefixes.(More)
Data dissemination strategies and communication protocols that minimize the use of energy can significantly prolong the lifetime of a sensor network. Data-centric dissemination strategies seek energy efficiency by employing short metadata descriptions in advertisements (ADVs) of the availability of data, short requests (REQs) to obtain the data by nodes(More)
Multiple data-centric protocols - which can broadly be classified as push-pull, push-only, or pull-only - have been proposed in the literature. In this paper we present a framework to develop an insight into the characteristics of push-pull protocols. The performance of push-pull protocols is critically dependent on the timeout settings used to trigger(More)
The Border Gateway Protocol (BGP), the de-facto Internet interdomain routing protocol, disseminates information about Internet prefixes to Autonomous Systems (ASes). Prefixes are announced and withdrawn as routes and policies change, making them unreachable from portions of the Internet for certain time periods. This paper aims to predict routing failures(More)
The reachability of IP address prefixes exhibits significant fluctuations due to changes in both physical connectivity and ISP routing policies. In the late 1990s, Labovitz et al. performed an extensive study of inter-domain path stability by analyzing BGP routing data. To reduce the noise in the BGP data, e.g., transient updates during route convergence,(More)
The Border Gateway Protocol (BGP) maintains inter-domain routing information by announcing and withdrawing IP prefixes, possibly resulting in temporary prefix unreachability. Prefix availability observed from different vantage points in the Internet can be lower than standards promised by Service Level Agreements (SLAs). In this paper, we(More)
One hundred and six consecutively seen psychiatric patients who had undergone detailed evaluation had their diagnosis compared with that arrived at in a walk-in evaluation one week to one month prior to the index evaluation. There was a diagnostic change in 21 cases and a change in drugs in 14. The pitfalls of this method for administering rapid efficient(More)
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