Firewalls: A Balance Between Security and Accesibility

Access control lists and firewall rules are intended to prevent access to certain resources on a computer network while allowing access to other resources. Access control lists determine who has access to resources while firewall rules prevent general access to resources. The goal of this research is to find the best way to optimize a campus internet connection as well as a balance between the application of rules and lists and the accessibility of the outside world. This research is done utilizing a simulated internet and local network environment. The environment utilized simulates the set-up currently in use by an educational institution and will serve as a test environment upon completion of my research

A Proposal for Dynamic Access Lists for TCP/IP Packet Filering

The use of IP filtering to improve system security is well established, and although limited in what it can achieve has proved to be efficient and effective. In the design of a security policy there is always a trade-off between usability and security. Restricting access means that legitimate use of the network is prevented; allowing access means illegitimate use may be allowed. Static access list make finding a balance particularly stark -- we pay the price of decreased security 100% of the time even if the benefit of increased usability is only gained 1% of the time. Dynamic access lists would allow the rules to change for short periods of time, and to allow local changes by non-experts. The network administrator can set basic security guide-lines which allow certain basic services only. All other services are restricted, but users are able to request temporary exceptions in order to allow additional access to the network. These exceptions are granted depending on the privileges of the user. This paper covers the following topics: (1) basic introduction to TCP/IP filtering; (2) semantics for dynamic access lists and; (3) a proposed protocol for allowing dynamic access; and (4) a method for representing access lists so that dynamic update and look-up can be done efficiently performed.Comment: 12 pages. Shortened version appeared in SAICSIT 200

Tight and simple Web graph compression

Analysing Web graphs has applications in determining page ranks, fighting Web spam, detecting communities and mirror sites, and more. This study is however hampered by the necessity of storing a major part of huge graphs in the external memory, which prevents efficient random access to edge (hyperlink) lists. A number of algorithms involving compression techniques have thus been presented, to represent Web graphs succinctly but also providing random access. Those techniques are usually based on differential encodings of the adjacency lists, finding repeating nodes or node regions in the successive lists, more general grammar-based transformations or 2-dimensional representations of the binary matrix of the graph. In this paper we present two Web graph compression algorithms. The first can be seen as engineering of the Boldi and Vigna (2004) method. We extend the notion of similarity between link lists, and use a more compact encoding of residuals. The algorithm works on blocks of varying size (in the number of input lines) and sacrifices access time for better compression ratio, achieving more succinct graph representation than other algorithms reported in the literature. The second algorithm works on blocks of the same size, in the number of input lines, and its key mechanism is merging the block into a single ordered list. This method achieves much more attractive space-time tradeoffs.Comment: 15 page

Opportunity-Rich Schools and Sustainable Communities: Seven Steps to Align High-Quality Education With Innovations in City and Metropolitan Planning and Development

Details challenges and steps for linking quality education and community and economic vitality, including establishing a shared vision and metrics, aligning investments for prosperity, and expanding access via transportation. Lists promising practices

What Shapes Health-Related Behaviors? The Role of Social Factors

Outlines how social factors such as education, income, and neighborhood conditions affect stress levels and access to healthy choices and medical care, in turn shaping health-related behaviors. Lists promising programs for creating healthier environments

Connecting Residents of Subsidized Housing With Mainstream Supportive Services: Challenges and Recommendations

Outlines challenges in expanding access to supportive services for older adults and families, including housing providers' lack of capacity or space to deliver services, limited direct funding, and restrictive eligibility rules. Lists HUD policy options

Automated Discovery of Internet Censorship by Web Crawling

Censorship of the Internet is widespread around the world. As access to the web becomes increasingly ubiquitous, filtering of this resource becomes more pervasive. Transparency about specific content that citizens are denied access to is atypical. To counter this, numerous techniques for maintaining URL filter lists have been proposed by various individuals and organisations that aim to empirical data on censorship for benefit of the public and wider censorship research community. We present a new approach for discovering filtered domains in different countries. This method is fully automated and requires no human interaction. The system uses web crawling techniques to traverse between filtered sites and implements a robust method for determining if a domain is filtered. We demonstrate the effectiveness of the approach by running experiments to search for filtered content in four different censorship regimes. Our results show that we perform better than the current state of the art and have built domain filter lists an order of magnitude larger than the most widely available public lists as of Jan 2018. Further, we build a dataset mapping the interlinking nature of blocked content between domains and exhibit the tightly networked nature of censored web resources

Boston Unplugged: Mapping a Wireless Future

Reviews a variety of models that would allow Boston to provide free or low-cost high-speed Internet access citywide. Outlines the benefits and mechanics of citywide WiFi, and lists factors to consider in designing, developing, and deploying a system