EE-WBC Assignment 6

Program 1 (40pts.)

Write a simple (one client at a time, no multithreading necessary) HTTP network scanner server application on port number 2005. Upon client connection the server should produce a Web page (full HTTP protocol) that contain:

• Information regarding the current connection:
  • The IP address and the hostname of the Server
  • The port number of the socket connection on the server
  • The IP address and the host name of the connecting client
  • The port number of the socket connection on the client side
• Information regarding open TCP/IP ports on the user's computer in the range 1 to 1024 nicely formatted.
• Use multithreading for fast port scanning but not necessarily for handling multiple clients that connects to the server at the same time.

The server should display information specified above in an HTML document in organized way. (Use a table to obtain tabelarized format.) The server should be contacted using a Web browser by entering the location http://your_computer_name_or_ip:2005/. You can use http://localhost:2005/ when you run both the server and the Web browser on the same computer while testing.

You can quickly determine whether a port is open on a computer by attempting to connect to its appropriate port number and then closing the connection. If no connection refused exception occurs that either a service is available or something else impersonates the said service. You do not have to verify whether that is the actual service that usually uses a particular port number. The port numbers are listed by each service for your convenience.

If you like to test your program in more interesting way, run the Web browser on CEGT201.bradley.edu or STUDENTS.bradley.edu. The easiest way is to run a text mode browser after connecting by telnet. On the Unix command prompt type lynx http://your_computer_name_or_ip:2005/

Extra Credit 2 (20pts.)

Make the server scalable by implementing multithreaded servicing of connected clients (Web browsers) so that scanning of multiple different machines could be performed at the same time. This requires significant changes to the port scanning subprogram as you cannot use static variables any longer to pass the address, to collect results and to count how many processes still run.

Homework Submission

Attach all source code in files with proper names and extensions (*.html, *.java, *.pl, *.php, .htaccess e.t.c.). Do not ZIP files together or include compiled files (e.g. *.class). In case of dynamic Web pages (JavaScript or CGI) or Java applets also send the complete URL (including http://) that points to a page on your Web site that demonstrates your homework. Send your homework via e- mail to the instructor at olekmali at bradley dot edu. Please set the message subject to: web-hw6.

Thank you.