A5 client side attacks 3 high performance websites

A5: “Client side” attacks.

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High-Performance Websites & Security Questions [20 pts]
Each question is worth 2 points.
Q1: In Public Key Encryption, when used for “privacy,” who generates the private and
public keys? The sender or the receiver of the cipher text?
A1: The Receiver
Q2: What is a “message digest” and where is it used?
A2: A Message digest is 1) the number produced by applying a cryptographic hash
function to a message and 2) it is used in digital signatures [underlined the two words
REQUIRED in the answer] and in HTTPS / secure transactions.
Q3: Why is the use of CSS sprites beneficial to the overall performance of a web page?
A3: Using image sprites reduces the number of HTTP requests and saves in the number
of open / close socket, operations with high overhead.
Q4: Why is it better to use GET instead of POST in AJAX requests?
A4: It is better to use GET instead of POST since GET sends the headers and the data
together, while POST sends the header and the data separately, resulting on higher
overhead.
Q5: List one role of a Certificate Authority (CA).
A5: Any one of these:
a) Guarantees that the organization is legitimate
b) Verifies the identity of an entity (client / server / e-mail address)
c) Issues digital certificates
d) Signs certificates with the CA’s private key
Q6: Where should you put style sheets and why to optimize performance?
A6: At the top, because some versions of Internet Explorer block rendering of the page
until all style sheets have been examined.
Q7: Where should you put scripts and why to optimize performance?
A7: At the bottom, because scripts block everything from rendering below them in the
page
Q8: Should you “inline” JavaScript code or use external files and why to optimize
performance?

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A8: Use external JavaScript files because they are cached
Q9: Should you scale images at the server or not scale images, and why?
A9: No, because scaling images should be performed at the client, to allow one of the
rules of “responsive” design
Q10: What are the “best” two rules that minimize the transfer of information between
server and browser?
A10: compression and minification (of scripts and CSS)
HTML5 Questions [10 pts]
Each question is worth 2 points.
Q1: Between the <canvas> and <svg> elements of HTML5, which one is best suited for
web applications with large rendering areas, such as Google Maps?
A1: SVG
Q2: Which of the following capabilities have included in HTML5?
A2:
[ X ] canvas
[ X ] video and audio
[ ] local SQL database
[ X ] geolocation
[ X ] CSS 2D/3D transformations
[ ] video plugin
[ ] flash plugin
[ ] ALL OF THE ABOVE
Q3: Why have FRAMES been removed from HTML5?