Tuesday, December 05, 2006
Web delivery and its discontents
Promises of Web delivery of applications have been circulating for years, but until ASP.NET 2.0 and its tools the technologies could rarely produce a credible and maintainable product. Microsoft has not been eating its own cooking from this kitchen. None of its major applications has been reimplemented for Web delivery. Lack of responsiveness comparable to client-based and client-server applications may have provoked the troubled "Atlas" effort, which at this juncture looks to be all hat and no cattle.
In favorable circumstances, AJAX technology can remedy the lack of responsiveness from Web delivery. There are two proven success cases: point update of a limited display from a large backing store, and continuous update of display borders to produce smooth scroll. However, AJAX is uncomfortable for software writers, because it disrupts orderly processing to gain performance.
Some vendors have been grandly promoting AJAX "frameworks" that more nearly resemble plaster patches for bunions. These home remedies all aim to reduce the amount of cookbook coding to process AJAX callbacks, but some, including Microsoft's and Telerik's, also try to relieve discomfort by providing orderly processing.
Results show one can't have it both ways. We recall "cold fusion," "artificial intelligence" and their great ancestor "perpetual motion." The overhead of orderly processing sacrifices the performance potential and yields nothing that anyone can take to the bank.
In favorable circumstances, AJAX technology can remedy the lack of responsiveness from Web delivery. There are two proven success cases: point update of a limited display from a large backing store, and continuous update of display borders to produce smooth scroll. However, AJAX is uncomfortable for software writers, because it disrupts orderly processing to gain performance.
Some vendors have been grandly promoting AJAX "frameworks" that more nearly resemble plaster patches for bunions. These home remedies all aim to reduce the amount of cookbook coding to process AJAX callbacks, but some, including Microsoft's and Telerik's, also try to relieve discomfort by providing orderly processing.
Results show one can't have it both ways. We recall "cold fusion," "artificial intelligence" and their great ancestor "perpetual motion." The overhead of orderly processing sacrifices the performance potential and yields nothing that anyone can take to the bank.
Monday, December 04, 2006
Quo vadis server transfer?
Nearly all professional quality Web Forms applications use Server.Transfer to switch pages rather than the easily hijacked cross-page posting approach. But when running under IIS in a virtual directory, where does Server.Transfer transfer?
With IIS 6.0, Server.Transfer stays within the same virtual directory if there is no directory component to the page path. A directory component may specify either a different virtual directory or a subdirectory. For an application contained within a single directory, only the original URL accessing the first page specifies the virtual directory.
With IIS 6.0, Server.Transfer stays within the same virtual directory if there is no directory component to the page path. A directory component may specify either a different virtual directory or a subdirectory. For an application contained within a single directory, only the original URL accessing the first page specifies the virtual directory.
Subscribe to Posts [Atom]