Policies are rules that govern the choices in behaviour of a system. Security policies define what actions are permitted or not permitted, for what or for whom, and under what conditions. Management policies define what actions need to be carried out when specific events occur within a system or what resources must be allocated under specific conditions. There is considerable interest in the use of policies for the security and management of large-scale networks and distributed services. Existing policy work has focussed on specification, information models and application-specific policy enforcement. We address the important goal of providing a general-purpose deployment model for policies that is independent of the underlying policy enforcement mechanisms and can be employed in mixed policy environments. In this paper, we present a deployment model that is object-oriented and addresses the instantiation, distribution and enabling of policies as well as the disabling, unloading and deletion of policies. The model defines objects for policies, for domains, and for policy enforcement agent and outlines the interactions needed between them. The model also caters for changes in the memberships of domains since such changes also effect policy enforcement. The model forms part of the runtime support for Ponder; a new policy language that combines structuring ideas from object-oriented languages with a common set of policy basic types.
Initiated in 2009 to emulate the GBTX (Gigabit Transceiver) serial link and test the first GBTX prototypes, the GBT-FPGA project is now a full library, targeting FPGAs (Field Programmable Gate Array) from Altera and Xilinx, allowing the implementation of one or several GBT links of two different types: "Standard" or "Latency-Optimized". The first major version of this IP Core was released in April 2014. This paper presents the various flavours of the GBT-FPGA kit and focuses on the challenge of providing a fixed and deterministic latency system both for clock and data recovery for all FPGA families.
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