Discuss whether it is possible to improve upon the ‘pull’ model of service discovery by multicasting (or broadcasting) and caching replies to queries.
What will be an ideal response?
We start with the ‘pull’ model described in the chapter but turn it into a hybrid with the ‘push’ model by having services multicast/broadcast their existence when a query occurs. All potential client devices can then hear and cache the service advertisements. When a component on the device requires a service, it first consults the local cache. If no matching services are found or if a more up-to-date list of matching services is required, then the device still multicasts its query. However, now it includes information about any matching services in its cache. Other potential clients may now learn about those services’ existence. Moreover, only services not in the query need reply.
While it is intuitively reasonable, this hybrid scheme needs validation through simultaion or experimentation against the required implementation parameters. The extra multicasts incur a cost.
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Once you have a document that passes the validation test, you may want to make a note of this on your Web page.
Answer the following statement true (T) or false (F)
What is a method that creates a hyperlink in ActionScript?
What will be an ideal response?
Identify the letter of the choice that best matches the phrase or definition.
A. JavaScript programmers call upon the services of one or more of these specialized functions that are within objects B. Provides the method with the information it needs to perform its function correctly C. Gives programmers the ability to evaluate a specific condition and then perform different actions depending on the results of that evaluation D. The line-by-line conversion process of scripts that occurs automatically at run time E. Specific rules of grammar in the Javascript language
You can change the ____, or position of text within a document's margins.
A. location B. proportion C. fielding D. alignment