This page has pointers to the simple software examples listed in the book.
HTTP Header Viewer
Enter the host address, such as
in the text box and press "submit" to retrieve and display the HTTP protocol header for that web object.
Try these examples:
www.cnn.com — because it is a popular host (with a trivial path),
www.content-networking.com/images/book.jpg — because it has a nontrivial path,
us.i1.yimg.com/us.yimg.com/i/yahoo.gif — because it is an old favorite and mentioned on page 54 of the book,
www.web-caching.com — because they use cache control directives.