With constant evolution of the Internet, many of its even well-established properties continue to change. This study re-evaluates the stability and diversity of Internet paths and whether it is affected by the widely deployed Multi-Protocol Label Switching (MPLS). In particular, using traceroutes between large number of source-destination pairs with the Internet Control Message Protocol (ICMP) extensions for the MPLS protocol, we study the stability and diversity of Internet paths as well as the amount of change in Round Trip Time (RTT) associated with a path change between a source-destination pair. Our results indicate that Internet routes are significantly less stable than previously reported. However, MPLS does not contribute significantly to this instability, and most path changes are associated with an insignificant change in RTT. While our route diversity results are not directly comparable with previous results, we find a great diversity of Internet routes: 60% of source-destination pairs in our experiments experienced 10 or more distinct routes in the course of 24 hours.

Today's Internet makes hosts and individual networks inherently insecure because permanent addresses turn destinations into permanent attack targets. This paper describes an Evasive Internet Protocol (EIP), a change to the data plane of the Internet that: 1) prevents senders from forging their identities while preserving the current Internet privacy paradigm; 2) gives recipients full control over who can communicate with them and for how long; 3) achieves the above features without requiring global signaling protocols; and 4) allows coexistence with and graceful introduction into the current Internet. We motivate our approach, present the architectural design, and evaluate it through trace-driven and synthetic simulations as well as prototype testing.

This paper develops a method for presenting the standard six-point Braille characters on mobile devices that feature tactile feedback. The proposed method views each Braille character as a two-column code, each column consisting of three points. The eight various combination of raised and lowered points of the three-point column are encoded with a single pattern of vibration, with the two columns of a Braille character are separated by a period of silence. The encoding scheme for the different point-combinations in a column is inspired by Morse code (a series of dots and dashes). Dots are represented by a small-duration vibration whereas dashes are represented by a longer-duration vibration. The encoding scheme is optimized to reduce the average reading time per character and to reduce the average power consumption per character. These optimizations target increasing the speed of reading and the mobile device's battery life respectively. As a proof-of-concept, the proposed method is implemented and tested with twelve blind users and three non-blind users. The different parameters of the proposed method were tuned based on the testing results. The overall results suggest that the proposed method significantly reduces the average reading time per character and reduces the average power consumption per character when compared to existing methods that utilize the mobile device's tactile feedback for presenting Braille characters.

This paper provides an indication that the distance between clients and their local DNS servers (LDNS) can have a significant negative impact on the performance of content delivery networks (CDNs). Consequently, we propose a novel peer-topeer client-side DNS mechanism that moves LDNS close to their clients while still allowing nearby clients to share the common DNS cache. Through trace-driven simulations and prototype testing, we show that our approach holds significant promise of facilitating better server selection by CDNs.

Decimal arithmetic has received considerable attention recently due to its suitability for many financial and commercial applications. In particular, numerous algorithms have been recently proposed for decimal multiplication. A major approach to decimal multiplication shaped by these proposals is based on performing the decimal digit-by-digit multiplication in binary, converting the binary partial product back to decimal, and then adding the decimal partial products as appropriate to form the final product in decimal. With this approach, the efficiency of binary-to-BCD partial product conversion is critical for the efficiency of the overall multiplication process. A recently proposed algorithm for this conversion is based on splitting the binary partial product into two parts (i.e., two groups of bits), and then computing the contributions of the two parts to the partial BCD result in parallel. This paper proposes two new algorithms (Three-Four split and Four-Three split) based on this principle. We present our proposed architectures that implement these algorithms and compare them to existing algorithms. The synthesis results show that the Three-Four split algorithm runs 15%faster and occupies 26.1%less area than the best performing equivalent circuit found in the literature. Furthermore, the Four-Three split algorithm occupies 37.5% less area than the state of the art equivalent circuit.

Web hosting providers are increasingly looking into dynamic hosting to reduce costs and improve the performance of their platforms. Instead of provisioning fixed resources to each customer, dynamic hosting maintains a variable number of application instances to satisfy current demand. While existing research in this area has mostly focused on the algorithms that decide on the number and location of application instances, we address the problem of efficient enactment of these decisions once they are made. We propose a new approach to application placement and experimentally show that it dramatically reduces the cost of application placement, which in turn improves the end-to-end agility of the hosting platform in reacting to demand changes.

Anycast-based content delivery networks (CDNs) have many properties that make them ideal for the large scale distribution of content on the Internet. However, because routing changes can result in a change of the endpoint that terminates the TCP session, TCP session disruption remains a concern for anycast CDNs, especially for large file downloads. In this paper we demonstrate that this problem does not require any complex solutions. In particular, we present the design of a simple, yet efficient, mechanism to handle session disruptions due to endpoint changes. With our mechanism, a client can continue the download of the content from the point at which it was before the endpoint change. Furthermore, CDN servers purge the TCP connection state quickly to handle frequent switching with low system overhead.

Actuator networks will enable an unprecedented degree of distributed control of physical environments, and further progress will critically depend on the availability of a simulation platform that can capture both the physical and the communication dynamics.