A Survey Of IPv6 Address Usage In The Public Domain Name System

The IPv6 protocol has been slowly increasing in use on the Internet. The main reason for the development of the protocol is that the address space provided by IPv4 is nearing exhaustion. The pool of addresses provided by IPv6 is 296 times larger than IPv4, and should be sufficient to provide an address for every device for the foreseeable future. Another potential advantage of this significantly large address space is the use of randomly assigned addresses as a security barrier as part of a defence in depth strategy. This research examined the addresses allocated by those implementing IPv6 to determine what method or pattern of allocation was being used by adopters of the protocol. This examination was done through the use of DNS queries of the AAAA IPv6 host record using public DNS servers. It was observed that 55.84% of IPv6 addresses were in the range of 0 to (232 − 1). For those addresses with unique interface identifier (IID) portions, a nearly equal number of sequential and random IIDs were observed. Hong Kong and Germany were found to have the greatest number of IPv6 addresses. These results suggest that adopters are allocating most addresses sequentially, meaning that no security advantage is being obtained. It is unclear as to whether this is through design or the following of accepted practice. Future research will continue to survey the IPv6 address space to determine whether the patterns observed here remain constant

Measurable realizations of abstract systems of congruences

An abstract system of congruences describes a way of partitioning a space into finitely many pieces satisfying certain congruence relations. Examples of abstract systems of congruences include paradoxical decompositions and $n$-divisibility of actions. We consider the general question of when there are realizations of abstract systems of congruences satisfying various measurability constraints. We completely characterize which abstract systems of congruences can be realized by nonmeager Baire measurable pieces of the sphere under the action of rotations on the $2$-sphere. This answers a question of Wagon. We also construct Borel realizations of abstract systems of congruences for the action of $\mathsf{PSL}_2(\mathbb{Z})$ on $\mathsf{P}^1(\mathbb{R})$. The combinatorial underpinnings of our proof are certain types of decomposition of Borel graphs into paths. We also use these decompositions to obtain some results about measurable unfriendly colorings.Comment: minor correction

A survey of IPV6 address usage in the public domain name system

The IPv6 protocol has been slowly increasing in use on the Internet. The main reason for the development of the protocol is that the address space provided by IPv4 is nearing exhaustion. The pool of addresses provided by IPv6 is 296 times larger than IPv4, and should be sufficient to provide an address for every device for the foreseeable future. Another potential advantage of this significantly large address space is the use of randomly assigned addresses as a security barrier as part of a defence in depth strategy. This research examined the addresses allocated by those implementing IPv6 to determine what method or pattern of allocation was being used by adopters of the protocol. This examination was done through the use of DNS queries of the AAAA IPv6 host record using public DNS servers. It was observed that 55.84% of IPv6 addresses were in the range of 0 to (232 − 1). For those addresses with unique interface identifier (IID) portions, a nearly equal number of sequential and random IIDs were observed. Hong Kong and Germany were found to have the greatest number of IPv6 addresses. These results suggest that adopters are allocating most addresses sequentially, meaning that no security advantage is being obtained. It is unclear as to whether this is through design or the following of accepted practice. Future research will continue to survey the IPv6 address space to determine whether the patterns observed here remain constant

Wellspring Waste to Energy Feasibility Study

This study was conducted by the University of Massachusetts Amherst public policy masters students for Springfield based Wellspring Cooperative, a nonprofit focused on cooperative job creation and training. The project assesses three potential scale options for Wellspring in order to use organic material to heat and/or generate electricity to power its hydroponic greenhouse. Though the greenhouse is not constructed as of yet, its source of energy is an important element for Wellspring. Motivations for utilizing organic waste to power the greenhouse are due in part to the influx of food waste sources being diverted due to the new Massachusetts Food Waste Ban. Indeed, new Massachusetts Department of Environmental Protection (DEP) restrictions on commercial food waste entering into landfills (CMR 310 19.017(3)) has created a conducive environment for composting and associated organic waste processing technology growth. Moreover, the commercial organic waste ban was a catalyst for Wellspring to contact the Center for Public Policy and Administration to determine what types of waste to energy technology could be incorporated to power their greenhouse and subsequent associated job growth. In assessing potential energy generation sources, we researched the technological aspects for a compost-to-heat system, a small scale anaerobic digester, and a large scale anaerobic digester. We then evaluated the relevant financial and implementation factors involved. we determined Wellspring\u27s goals of waste to energy generation should be framed through the context of a short term and long term lens. The recommended short term strategy is to utilize composting systems to heat the greenhouse and connect the greenhouse to the electrical grid. The recommended long term strategy includes partnering with the City of Springfield to develop an organic waste processing facility that would generate electricity from food, animal, and human waste and/or contract with the city as a food waste hauler. With these recommendations we believe that Wellspring will achieve its goals and lead the way in sustainable energy generation

Folner tilings for actions of amenable groups

We show that every probability-measure-preserving action of a countable amenable group G can be tiled, modulo a null set, using finitely many finite subsets of G ("shapes") with prescribed approximate invariance so that the collection of tiling centers for each shape is Borel. This is a dynamical version of the Downarowicz--Huczek--Zhang tiling theorem for countable amenable groups and strengthens the Ornstein--Weiss Rokhlin lemma. As an application we prove that, for every countably infinite amenable group G, the crossed product of a generic free minimal action of G on the Cantor set is Z-stable.Comment: Minor revisions. Final versio