Hakim Weatherspoon

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OceanStore is a utility infrastructure designed to span the globe and provide continuous access to persistent information. Since this infrastructure is comprised of untrusted servers, data is protected through redundancy and cryptographic techniques. To improve performance, data is allowed to be cached anywhere, anytime. Additionally, monitoring of usage(More)
The increasing popularity of cloud storage is leading organizations to consider moving data out of their own data centers and into the cloud. However, success for cloud storage providers can present a significant risk to customers; namely, it becomes very expensive to switch storage providers. In this paper, we make a case for applying RAID-like techniques(More)
This paper considers replication strategies for storage systems that aggregate the disks of many nodes spread over the Internet. Maintaining replication in such systems can be prohibitively expensive, since every transient network or host failure could potentially lead to copying a server’s worth of data over the Internet to maintain replication levels. The(More)
OceanStore is an Internet-scale, persistent data store designed for incremental scalability, secure sharing, and long-term durability. Pond is the OceanStore prototype; it contains many of the features of a complete system including location-independent routing, Byzantine update commitment, push-based update of cached copies through an overlay multicast(More)
Peer-to-peer systems are positioned to take advantage of gains in network bandwidth, storage capacity, and computational resources to provide long-term durable storage infrastructures. In this paper, we quantitatively compare building a distributed storage infrastructure that is self-repairing and resilient to faults using either a replicated system or an(More)
The computing world is experiencing a transition from desktop PCs to connected information appliances, which — like the earlier transition from mainframes to PCs — will profoundly change the way information is used. The variety of devices capable of connecting to the Internet is astounding. Personal Data Assistants (PDAs), cellular phones, and even cars(More)
Current Infrastructure as a Service (IaaS) clouds operate in isolation from each other. Slight variations in the virtual machine (VM) abstractions or underlying hypervisor services prevent unified access and control across clouds. While standardization efforts aim to address these issues, they will take years to be agreed upon and adopted, if ever. Instead(More)
Maintaining data replication levels is a fundamental process of wide-area storage systems; replicas must be created as storage nodes permanently fail to avoid data loss. Many failures in the wide-area are transient, however, where the node returns with data intact. Given a goal of minimizing replicas created to maintain a desired replication level, creating(More)
The global network of datacenters is emerging as an important distributed systems paradigm — commodity clusters running high-performance applications, connected by high-speed ‘lambda’ networks across hundreds of milliseconds of network latency. Packet loss on long-haul networks can cripple application performance — a loss rate of 0.1% is sufficient to(More)
Many wide-area storage systems replicate data for durability. A common way of maintaining the replicas is to detect node failures and respond by creating additional copies of objects that were stored on failed nodes and hence suffered a loss of redundancy. Reactive techniques can minimize total bytes sent since they only create replicas as needed; however,(More)