Web Server Design Assignment #2: Conditionals & Persistence Old Dominion University Department of Computer Science CS 495/595 Spring 2006 Michael L. Nelson <mln@cs.odu.edu>

Grading To be done by an automated program that will test most (all?) combinations assignment is listed under the day it is to be demoed in class each group will give a 3-4 minute status report the week before an assignment is due! If you have a question: email the class list mimic the behavior of a well known Apache server (e.g., www.cs.odu.edu)

Methods to Support Same as assignment #1

Status Codes to Support Same as assignment #1, plus: 301 Moved Permanently 304 Not Modified 412 Precondition Failed

Request Headers Same as assignment #1, but: and add: optional: Connection: close and add: If-Modified-Since If-Unmodified-Since If-Match If-None-Match

Response Headers Same as assignment #1, plus: ETag

MIME Types Same as assignment #1

Further Guidance Only “strong” ETags need to be computed Use a logical “AND” when combining: If-Modified-Since If-Unmodified-Since If-Match If-None-Match be stingy: all conditions must be satisfied to send data if conditionals would yield both 304 & 412, then send only the 304 Terminate connections after 15 idle seconds