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.