This paper introduces a framework for evaluating replica placement algorithms (RPA) for content delivery networks (CDN) as well as RPAs from other fields that might be applicable to current or future CDNs. First, the framework classifies and qualitatively compares RPAs using a generic set of primitives that capture problem definitions and heuristics. Second, it provides estimates for the decisi...

The replica placement problem has been well studied on trees. In this paper, we study this problem on directed acyclic graphs. The replica placement problem on general DAGs generalizes the set cover problem. We present a constant factor approximation algorithm for the special case of DAGs having bounded degree and bounded tree-width (BDBT-DAGs). We also present a constant factor approximation a...

Farsite is a secure, scalable, distributed file system that logically functions as a centralized file server but that is physically realized on a set of client desktop computers. Farsite provides security, reliability, and availability by storing replicas of each file on multiple machines. It continuously monitors machine availability and relocates replicas as necessary to maximize the effectiv...

Virtual machine (VM) replication is a critical task in any cloud computing platform to ensure the availability of service for end user. In this task, one primary VM resides on physical (PM) and or more replicas reside separate PMs. computing, placement (VMP) well-studied problem terms different goals, such as power consumption reduction. The VMP can be solved by using heuristics, namely, first-...

Content Delivery Networks (CDN) aim at overcoming the inherent limitations of the Internet. The main concept at the basis of this technology is the delivery at edge points of the network, in proximity to the request areas, to improve the user’s perceived performance while limiting the costs. This paper focuses on the main research areas in the field of CDN, pointing out the motivations, and ana...

Recently there has been an increasing deployment of content distribution networks (CDNs) that offer hosting services to Web content providers. CDNs deploy a set of servers distributed throughout the Internet and replicate provider content across these servers for better performance and availability than centralized provider servers. Existing work on CDNs has primarily focused on techniques for ...

Transparent data replication has been considered a promising technique for improving system performance for a large distributed network. In this paper, a hybrid transparent replication model is presented. We address the problems of replication proxy placement in the network and data replica placement on the installed proxies given that a maximum of proxies are allowed. Both reads and writes are...

Jgroup/ARM is a middleware for developing and operating dependable distributed Java applications. Jgroup integrates the distributed object model of Java RMI with the object group paradigm, enabling construction of replicated servers that offer dependable services to clients. ARM aims to improve the dependability characteristics of systems through fault treatment, focusing on operational aspects...