Jorge Londoño

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Emerging configurable infrastructures (large-scale overlays, grids, distributed testbeds, and sensor networks among others) comprise diverse sets of computing resources and network conditions. The distributed applications to be deployed on these infrastructures exhibit increasingly complex constraints and requirements on the resources they require. Thus, a(More)
We introduce Collocation Games as the basis of a general framework for modeling, analyzing, and facilitating the interactions between the various stakeholders in distributed systems in general, and in cloud computing environments in particular. Cloud computing enables fixed-capacity (processing, communication, and storage) resources to be offered by(More)
The advent of virtualization and cloud computing technologies necessitates the development of effective mechanisms for the estimation and reservation of resources needed by content providers to deliver large numbers of video-on-demand (VOD) streams through the cloud. Unfortunately, capacity planning for the QoS-constrained delivery of a large number of VOD(More)
We introduce Colocation Games as the basis of a general framework for modeling, analyzing, and facilitating the interactions between the various stakeholders in distributed/cloud computing environments, where resources are offered in an open marketplace to independent, rational parties interested in setting up their own applications. Virtualization(More)
By colocating with other tenants of an Infrastructure as a Service (IaaS) offering, IaaS users could reap significant cost savings by judiciously sharing their use of the fixed-size instances offered by IaaS providers. This paper presents the blueprints of a Colocation as a Service (CaaS) framework. CaaS strategic services identify coalitions of(More)
BACKGROUND Abdominal pregnancy is not encountered commonly, and management of the placenta is controversial. CASE A 33-year-old woman presented with an abdominal pregnancy at 33 weeks' gestation with fetal death. The placental vasculature was embolized preoperatively. Following operative delivery. of the fetus, the placenta was left in situ in efforts to(More)
By colocating with other tenants of an Infrastructure as a Service (IaaS) offering, IaaS users could reap significant cost savings by judiciously sharing their use of the fixed-size instances offered by IaaS providers. This paper presents the blueprints of a Colocation as a Service (CaaS) framework. CaaS strategic services identify coalitions of(More)
UNLABELLED Presacral tumors are rare with few published studies in the literature. It is unknown whether the course of the disease and the required treatment differs between pediatric and adult patients. The aim of the study was to compare presenting symptoms, surgical treatment, pathology, and recurrence rates of presacral tumors in these two groups. (More)
We propose Trade & Cap (T&C), an economicsinspired mechanism that incentivizes users to voluntarily coordinate their consumption of the bandwidth of a shared resource (e.g., a DSLAM link) so as to converge on what they perceive to be an equitable allocation, while ensuring efficient resource utilization. Under T&C, rather than acting as an arbiter, an(More)
In this paper we examine a number of admission control and scheduling protocols for high-performance web servers based on a 2-phase policy for serving HTTP requests. The first ``registration'' phase involves establishing the TCP connection for the HTTP request and parsing/interpreting its arguments, whereas the second ``service'' phase involves the(More)