Distributed Access Control with Blockchain

The specification and enforcement of network-wide policies in a single administrative domain is common in today's networks and considered as already resolved. However, this is not the case for multi-administrative domains, e.g. among different enterprises. In such situation, new problems arise that challenge classical solutions such as PKIs, which suffer from scalability and granularity concerns. In this paper, we present an extension to Group-Based Policy -- a widely used network policy language -- for the aforementioned scenario. To do so, we take advantage of a permissioned blockchain implementation (Hyperledger Fabric) to distribute access control policies in a secure and auditable manner, preserving at the same time the independence of each organization. Network administrators specify polices that are rendered into blockchain transactions. A LISP control plane (RFC 6830) allows routers performing the access control to query the blockchain for authorizations. We have implemented an end-to-end experimental prototype and evaluated it in terms of scalability and network latency.Comment: 7 pages, 9 figures, 2 table

GAME MODELS OF ENVIRONMENTAL POLICY IN AN OPEN ECONOMY

In this paper we study some aspects of the question of international environmental regulation from a game theoretic perspective. We address two broad questions. First, we examine the circumstances under which the pursuit of unilateral environmental policy by a country in a Stackelberg game will make that country worse off. Second, we study the effects of environmental regulation by means of alternate price control instruments in a Stackelberg game where there is transboundary pollution. We find that there are plausible theoretical circumstances in which the pursuit of unilateral environmental policy is not a good idea. Further, we show that in choosing between alternate pollution control instruments, national governments typically face a tradeoff between instruments which correct more distortions but are costly to implement and instruments which correct fewer distortions but are less costly to implement. In particular, we obtain a dominance result for a tariff policy; this result favors the use of tariffs from an informational standpoint alone. Published in Annals of Regional Science 30 (2, 1996): 185-200.environmental, policy, open, economy, game, Environmental Economics and Policy, D62, F13, Q28,

Effects of the CDM on Poverty Eradication and Global Climate Protection

In an impure public good model we analyze the effects of CDM transfers on poverty as well as on the global climate protection level. We construct an analytical model of a developing and an industrialized region, both of which independently seek to maximize their utility – a function of private consumption, domestic air quality, and global climate protection. They do so by distributing their finite expenditures across (1) the aggregate consumption good, (2) end-of-pipe pollution control technologies, and (3) greenhouse gas abatement. Based on our analytical findings, we develop two sets of simulations for China in which we vary the rate of the CDM transfer. The simulations differ by the assumption of China’s domestic air quality policy – the first assumes a technology-standards policy which fixes a level of end-of-pipe SO2 control, whereas the second assumes a technology-neutral policy which simply fixes the level of total SO2 emissions.Ancillary Benefits, CDM, Climate Policy, Impure Public Goods, Transfers, Abatement Technology

Combining emissions trading and emissions taxes in a multi-objective world

The combination of emissions trading and emissions taxes is usually rejected as redundant or inefficient. This conclusion is based on the restrictive assumption that both policies are exclusively meant to control pollution. However, particularly taxes may pursue a variety of other policy objectives as well, such as raising fiscal revenues or promoting equity. Multiple objectives may justify multiple policies. In this case, welfare losses with respect to pollution control may be traded off by benefits from attaining other policy objectives. Consequently, pragmatic policy recommendations have to be based on an in-depth understanding of interactions in the policy mix. This article makes three contributions that are relevant in this respect. (1) The most important factors distorting pollution abatement under the policy mix are identified. This insight is required to estimate the actual extent of inefficiency in controlling pollution, and to compare it with benefits of attaining other objectives of the tax. (2) The policy mix is not only compared to the unrealistic ideal of an efficient single emissions trading scheme but also to a suboptimal heterogeneous emissions tax. It is shown that if the tax is required to address multiple policy objectives, the implementation of an emissions trading scheme in addition may in fact increase the efficiency of pollution control. (3) It is demonstrated that welfare losses can be minimized within a policy mix by modifying emissions trading design. --policy mix,emissions trading,emissions tax,efficiency