Arindam Mitra

Trust Brokering and Its Use for Resource Matchmaking in Public-Resource Grids

This paper presents a trust brokering system that operates in a peer-to-peer manner. The network of trust brokers operate by providing peer reviews in the form of recommendations regarding potential resource targets. One of the distinguishing features of our work is that it separately models the accuracy and honesty concepts. By separately modeling these concepts, our model is able to significantly improve the performance. We apply the trust brokering system to a resource manager to illustrate its utility in a public-resource Grid environment. The simulations performed to evaluate the trust-aware resource matchmaking strategies indicate that high levels of ‘robustness’ can be attained by considering trust while matchmaking and allocating resources.

Wide-area content-based routing mechanism

Content networking is an emerging technology, where the requests for content are steered by content routers that examine not only the destinations but also content descriptors such as URL and cookies. In the current deployments of content networking, content routing is mostly confined to selecting the most appropriate back-end server in virtualized Web server clusters. In this paper, we present an architecture for wide-area content routing. The architecture is based on tagging the requests at ingress points. The tags are designed to incorporate several different attributes of the content in the routing process. Simulations are carried out to compare the performance of the proposed scheme with a DNS-based content access scheme.

Towards a quality of service aware public computing utility

This work describes a design for a quality of service aware public computing utility (PCU). The goal of the PCU is to utilize the idle capacity of the shared public resources and augment the capacity with dedicated resources as necessary, to provide high quality of service to the clients at the least cost. Our PCU design combines peer-to-peer (P2P) and grid computing ideas in a novel manner to construct a utility-based computing environment. In This work, we present the overall architecture and describe two major components: a P2P overlay substrate for connecting the resources in a global network and a community-based decentralized resource management system.

Benefits of Targeting in Trusted Gossiping for Peer-to-Peer Information Sharing

In a recent study, we proposed a trusted gossip protocol for rumor resistant information sharing in peer-to-peer networks. While trust aware gossiping significantly reduced the rumor spread on the network, we observed that the random message spraying in trusted gossip creates too many redundant messages increasing the message overhead and error rate. In this paper, we propose a message targeting scheme that can significantly improve the performance of the trusted gossip. Our targeting scheme can be easily implemented in a social network setting. We performed large-scale simulations using traces collected from the Flickr social network and other data sets to estimate the performance of targeting in trusted gossip. Our experiments show that significant performance gains can be achieved.

Trusted Gossip:A Rumor Resistant Dissemination Mechanism for Peer-to-Peer Information Sharing

Epidemic protocols such as gossip have proven to have many desirable properties for information sharing. However, trust is one of the issues that is yet to be examined with respect to these protocols. In this paper, we present a trusted gossip protocol that uses trust estimates to impede spreading of rumors with reasonable message and processing overheads. We use traces collected from known social networks to estimate the performance of trusted gossip.

A secure trust and incentive management framework for public-resource based computing utilities

Trust and security are two major issues in large distributed systems that are highly inter-dependent such that it is hard to bootstrap one without the other. In distributed systems that are built using private resources, security is bootstrapped using off-line trust relationships. Mandating off-line trust relations, however, has the undesirable effect of limiting the membership of distributed systems. Therefore, public-resource based systems need online trust modeling. This paper presents a two-layered framework that considers trust, security and incentives in an integrated fashion. Our framework is characterized by (a) a community-based process that is essentially decentralized for evaluating and assigning trust for peers (b) policy autonomy in administering incentives and trust, and (c) lowers the join time trust requirements for peers. Results from early prototyping and simulations show the proposed framework can be implemented with acceptable overheads and is capable of evolving trust and applying it for resource management.

Impact of Peer Churning in Trusted Gossiping for P2P Information Sharing

In a recent study we proposed a trusted gossip protocol for rumor resistant information sharing in peer-to- peer networks. Experiments using trace data collected from social networks like Flickr and other data sets showed that the trusted protocol can achieve significant reductions in rumor spreading with reasonable message and processing overheads. The study, however, did not consider node churn - a continuous process of node arrival and departure. In this paper, we show through experiments that the trusted gossip protocol can continue to perform equally well with churning nodes as in no-churn situations. We examine the trusted gossip protocol using synthetic and real traces for node churning collected from the Myspace social network. Our experiments show that the trusted protocol performance is considerably resilient even to extreme churning conditions.