Tech Talk

Ajax is getting a lot of tech buzz these days.  Making RPCs from client-side javascript is not a new technological innovation. Techniques such posting to hidden frames, posting to IFrames, and using Applets for server-side communication have been around for more than ten years.  

Back in 2000 I wrote a Web based Client Service Rep (CSR) application for a Appliance Warehouse.   It was a call center application used by CSRs to process customer orders for appliance rentals: washers, dryers, etc.  The application was designed to replace an existing client-server, windows-based application.  A key requirement was for the Web application to behave like the windows application it replaced (i.e. minimal or no screen refresh/browser form posts).

In 1999 Microsoft released an Applet-based RPC technique for javascript called Remote Scripting. This is the solution that I implemented for the CSR application. 

It's nice to see the resurgence of these javascript RPC methodologies albeit rebranded as "AJAX".  I now only use the XmlHttpRequest methodologies lauded by Ajax proponents, however; Remote Scripting can still be leveraged today.  An article posted by Peter Bromberg has some nice examples.

Here are some resources for Remote Scripting:

Microsoft Remote Scritpting

Brent Ashley's Remote Scripting Resources

Most software developers have either been asked a Fermi question in an interview or know of someone that has been asked this type of question.  Companies like Microsoft and Google are notorious for asking these questions. 

Why do interviewers ask this type of question?

Most developers I've talked to generalize the purpose of these questions as "They want to evaluate your critical thinking skills." Wikipedia's definition states that a Fermi problem:  is an estimation problem designed to teach dimensional analysis, approximation, and the importance of clearly identifying one's assumptions.

More specifically, the interviewer wants to determine how adept you are at creating quick, reasonably accurate estimations.   People who possess this skill augment a team's ability to quickly arrive at solutions when time and effort required to gather hard data is costly, impractical, or impossible. 

Here's a few links, so you can brush up on your Fermi skills:

http://www.soinc.org/events/fermiq/fermiguide.htm

http://www.vendian.org/envelope/dir0/fermi_questions.html

http://www.physics.uwo.ca/science_olympics/events/puzzles/fermi_questions.html