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<p style=We can all cite examples of technologies that took off simply because there was enough marketing muscle behind them, whether the technology was valid or not. I'm not trying to imply that near-field communications (NFC) is not a valid technology, but I am implying that if Nokia, Philips, and Sony really want this wireless medium to prosper, it has the marketing muscle to ensure its success. The three companies have come together to form the NFC Forum, which now includes more than 20 members.

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AVX, for example, is driving forward with plans to ramp tantalum-capacitor production. Last year, the company raised its capacity by 30%. By fall, company officials expect to increase capacity another 25%.

It has long been an acknowledged shortcoming of conventional object-oriented programming that data is still too tightly hard-coded into the object's design and implementation. Adaptivity is a necessary next step in software engineering. Applications need to be able to communicate with and adapt to one another-transparently. Moreover, compound applications -especially distributed ones- need to expect change in their components during the lifetime of the application, as well as change in the way these components interface among themselves and with other applications. On the other hand, object interrelationship should also be transparent. Objects need to rely as little as possible on another object's existence to perform their tasks.

Different approaches have been proposed over the past decade to come up with an alternative to conventional object-oriented practices. Arguably, the most prominent of these is the Demeter method, which deals with defining strategies for object-graph traversal. In an adaptive system, careful design is given to isolating objects from one another and isolating data from the operations and methods, that is, the behavior, defined in the object.

tea2025

We can use XML to design a simple messaging system that hides the communicating objects from one another and holds the data manipulated by the objects in sort of a parallel universe. If XML is our database, then DOM is its object model. In effect, the DOM can be viewed as a treelike data structure that fully represents an XML document. The DOM defines elements, nodes, attributes and entities, among other objects. It makes the XML document programmatically accessible not only as text, but also as an object graph.

The messaging system would need some MessageParticipant objects that participate in system-wide messaging. It is important that the objects have three attributes: no knowledge of one another; ability to accept and send messages; and ability to process the data received.

The first point is important because the objects that participate in messaging can and often will change over time. We use a switchboard object to keep a centralized reference repository, or registry, of the different MessageParticipants and the data flavors they are interested in.

tea2025

The flow will typically start when a MessageParticipant sends a message object to the system. In effect, the MessageParticipant does not know where it is sending the message-it wraps the message in a MessageAgent and sends it on its way. Next, the MessageAgent hands the switchboard the document contained in the message. Basically, the switchboard processes the document and finds other MessageParticipants that are registered as expecting the data flavors held in this document. For every such object, the switchboard creates a new document that holds exclusively the expected data flavors, and passes it to the registered MessageParticipant.

The MessageParticipant compares the document against its master document-in effect, a container for the object's state. The master document holds the expected values and optionally gets updated with the new state. In our messaging system we would need to frequently access the DOM documents that are passed around as messages or those that are in the master document. It is convenient to create an object that translates the DOM document into a Java collection for use as a data structure.

tea2025

For this we will build an object called DocumentMap that acts as the translator. The DocumentMap creates a mapping of a document passed into its constructor as an argument. The constructor internally calls process nodes for every node in the document and stores that node as a key in an internal map, or TreeMap.

Any MessageParticipant propagates the set of keys (tag names) in its master document to the switchboard. The switchboard's registry holds mappings between those tags and the set of MessageParticipants that deal with them.

Meanwhile, there are processors that don't support all the implementations of the Internet protocols. In the real world, the Internet protocols are implemented differently from server to server. You may deploy a device with a specific set of protocol support, only to find out that it does not work with every ISP. For example, there are three major authentication methods (PAP, CHAP and scripts) used in the PPP (point-to-point protocol) for dial-up applications. Within the CHAP protocol, there is a subset created by Microsoft called MSCHAP. If your device does not support one of these methods, it will not communicate with the ISP. Thus, you must rewrite the device's protocol stack and, therefore, the API.

Dynamic environment

The Internet is a dynamic environment. Regardless of which hardware or software solution you choose, the host application must be reprogrammed in order to accommodate any changes in the Internet protocols. For example, IMAP will replace POP3 as the preferred protocol for retrieving e-mail from the user's mailbox at his ISP. Also, IP Version 5 will be replaced by IP Version 6, creating a new set of IP addresses that cannot be supported by devices using the current IP version. That means going back into the application and rewriting the code that invokes the Internet protocols as well as the API.

Looking at these problems, developers and engineers at Connect One developed a new protocol that builds on the familiar Hayes's AT command set built into most phone line modems. Called AT+ i, it accelerates the building of Internet connectivity into almost any device by simplifying the writing and updating of an application programming interface on any device with an existing processor and operating system. Furthermore, it serves as the glue between the host device and the Internet connection.

The design of the AT+ i protocol had three aims. First, remove the complexity from the host to access the Internet protocols. Second, simplify the writing and debugging of new applications. Third, use a familiar format (the AT command set) for design engineers to set and interrogate parameters for dial-up applications using an Internet modem. The two components of the AT+ i command set are the command execution block and the interpreter block.

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I believe we could make no bigger mistake,” he said in his report, Why Silicon ValleyShould Not Normalize Relations with Washington, D.C.” Silicon Valley is what it is because of the values that drive our success. Politics is antithetical to — and highly destructive of — our core values.”

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