Issue No. 05 - September/October (2007 vol. 11)
DOI Bookmark: http://doi.ieeecomputersociety.org/10.1109/MIC.2007.106
Dr. Dobb's Journal
"Java Message Service," by Eric J. Bruno
As distributed computing continues to grow, choosing the right software design to help geographically separated computers communicate more effectively becomes even more important. Although SOAP has made significant strides in this area, Bruno argues that message-oriented middleware, such as Java Message Service (JMS; http://java.sun.com/products/jms), is the better choice for reliability, performance, and security. JMS is a specification that outlines the behavior and properties of an "information pipe" for Java software. It also describes how Java client applications interact with the pipe.
Messaging systems include messages, senders, and receivers in a loose connection, so changes to one part of the system won't affect the entire system, thereby allowing for more robust software. Every messaging system includes a broker that delivers messages and interacts with the system as a whole.
Bruno says JMS supports two message paradigms: point-to-point (or queue-based) messaging such as email, and publish-and-subscribe (or topic-based) messaging. With these, JMS supports the common client-server communication, the request-and-reply concept. Bruno also describes how to implement JMS applications, offering sample email sender and reader applications.
Mobile & Wireless Computing
25 June 2007
"Upgrading to 802.11n: Better Late than Early," by Dave Molta
The final 802.11n wireless standard isn't due for release until the end of 2008, but many enterprise IT professionals are already feeling pressured to make the switch. Molta says it's "fashionable" to believe a day will come when Wi-Fi, or some other technology, will be the preferred basis of enterprise network access, but 802.11n's drawbacks outweigh its possible benefits. Those drawbacks include difficulties with availability, scalability, and security, as well as higher costs than wired options.
Molta says not to be fooled by the enterprise Wi-Fi market's recent growth, most of which has come from higher education, where wireless local area networks (WLANs) are chosen to attract students rather than increase productivity.
Although the base technology for 802.11n is solid, and the Wi-Fi Alliance has certified products based on the draft standard, Molta predicts it will be at least two years before half of enterprise devices are 802.11n-enabled.
"Dog Tags for Virtual Sniffing," by Clark Boyd and "Sensor City," by Kate Greene
Snif Labs — Snif is short for Social Networking in Fur — has started distributing devices for dog collars that swap identification codes with other Snif devices that come within range. Owners can then use Snif's service to exchange information about their dogs or themselves. The startup from MIT's Media Lab also lets owners monitor pets at home via the Internet.
Internet & Society
"Building an Immersive Web," by Colin J. Parris
Second Life's early success in the virtual world seems to indicate that graphically rich, 3D online environments have the power to revolutionize the way we interact with each other and computers. Parris says the key is to engage two fundamental human characteristics: our social and visual tendencies. However, he argues, the technological and business arenas must begin to collaborate now if these kinds of platforms are to offer other feasible uses to consumers and businesses. Parris outlines three issues that must be tackled immediately to achieve that goal: creating open standards to join various virtual worlds, creating dependable ways to manage identity and trust issues, and incorporating business applications and data into virtual worlds.
Programming & Development
Dr. Dobb's Journal
"A Fast Q&A System," by Manu Konchady
Anyone who has used a typical search engine knows that you can't ask it a question and get a straight answer. Instead, you look for keywords and cull the answer from a list of possibly relevant links.
Konchady asserts that most question-answer (Q&A) systems address these drawbacks. He goes on to explain the basics of designing and implementing Q&A systems by reviewing the first step in the processing pipeline — categorizing questions — which classifies answers into options such as a person, place, animal, organization, and so on. He also explains how to extract entities, which are typically nouns that stand for a person, organization, or place. Konchady outlines query transformation and the generation of a query from a question, possibly the process's most important step before describing how to execute your own experimental Q&A system.
7 Aug. 2007
"Closing the Loopholes on Data Theft," by Cyrus Farivar
According to the Privacy Rights Clearinghouse, more than 100 million electronic records containing personal information were compromised in 2005–2006. That doesn't include the 45 million credit- and debit-card numbers reported stolen from Marshalls's and T.J. Maxx's parent company in January 2007. The statistics have spurred some US lawmakers to urge new federal laws to protect consumers.
Three federal bills to address this are beginning to wind their way through the US Senate, including the Personal Data Privacy and Security Act of 2007, which would force companies and governments to notify consumers, law enforcement, and credit-reporting agencies if a breach could be a "significant" risk to consumers.
17 July 2007
"Extreme Peer-to-Peer," by Jamie Bsales and Cade Metz
The Palo Alto Research Center (PARC) is in the midst of developing a project — Content Centric Networking (CCN) — that uses peer-to-peer concepts it hopes will revolutionize the way PC networking is viewed.
Similar to PC networks, CCN centers on the data instead of the server. As a result, PCs don't inquire about specific servers to retrieve data, which could involve bypassing much closer machines that have that same data. Instead, users inquire about data to all the machines on a network; if one of them has the data, it sends it.
"You can authenticate and validate information using the information itself — independent of whom you got it from," says PARC's Van Jacobson. "So if you want The New York Times, you can pick it up from any machine that has a copy."
Jacobson hopes to introduce CCN on top of the networks used today, similar to how BitTorrent, the peer-to-peer file distribution tool, was rolled out across the existing Internet.
Dr. Dobb's Journal
"SOA, Web Services, and RESTful Systems," by Eric J. Bruno
Web services are an improvement of client-server systems largely because they don't have platform constraints and yet are standardized and scalable.
But representational state transfer (REST) is a service-oriented architecture (SOA) that's even less restrictive than Web services, Bruno says. As outlined by Roy Fielding in his doctoral dissertation, REST's only requirement is that it be based on HTTP.
Bruno, who has built several RESTful services, also describes the basics of building a SOA-based RESTful system and describes a REST service framework he built to avoid writing duplicate code for each service he needs.