Explain the purpose of each of the HTTP request types when used with a RESTful web service.

Explain the basic structure of a MIME multipart message when used to transfer different content type parts. Provide a simple example.

What is Long polling, how does it work, and why would you use it? Considering server and client resources, what is the main drawback of using long polling? Which HTML5 feature is the best alternative to long polling?

Consider the following JavaScript code that is executed in a browser: function startAjaxQueue(){ for (var i = 0; i < 50; i++){ executeAjaxCallAsync(); } }; Assuming that executeAjaxCallAsync() uses a standard XmlHttpRequest asynchronously to retrieve data from server, how many concurrent HTTP requests would you expect to be created by this loop?

What is an ETag and how does it work?

Describe the key advantages of HTTP/2 as compared with HTTP 1.1.