• A [3 points]: This new echo server should conform to the RFC document for the echo protocol given in class. This includes modifying the server to process each connection until the client disconnects. In other words, the server should loop around the recv/send part until the recv returns a value of 0 bytes received.
• B [2 points]: It should have the ability to take the port number to bind to from the command line.
• C [10 points]: It should handle multiple connections concurrently. For C/C++, this means adding usage of fork() and reaping all child processes or using POSIX threads. For Java, the use of the Thread class will be necessary. Follow a process per connection or thread per connection model as appropriate.

• A [10 points]: Construct a routine or object to parse a given URL string in the form http://hostname[:portnum]/pathname, where the part in [] is optional, into (1) host IP address, (2) port, and (3) URI. You may not rely on any intrinsic language objects that do URL parsing for you.
• B [10 points]: Construct a routine that uses the routine or object above to take a URL, connect to the correct web server, send a HTTP/1.0 HEAD request, and retrieve the response. You may not rely on any intrinsic language objects that do HTTP retrieval for you.
• C [15 points]: Take the routines or objects constructed in the parts above and construct an application that takes a filename that holds a set of URLs (one per line) and tests each URL in turn. For each URL, the application must print: (1) the URL, (2) whether the web site was reachable (if not, then why), (3) response code from the request (if any), and (4) information from the HTTP headers that specify the object (if any). The HTTP headers to be parsed are "Content-Type" and "Content-Length". You may not rely on any intrinsic language objects that do HTTP parsing for you.

• A [5 points]: Construct a routine or object that can read an HTTP/1.0 request from a socket and parse it into request method, request-URI, HTTP version, headers, etc.
• B [5 points]: Construct a routine or object to construct a HTTP/1.0 response given a status code, phrase, headers, and a body and send that response back on a socket.
• C [10 points]: Take the routines or objects constructed above and construct an application that listens on a port for connections. Connections that are accepted should then be treated like HTTP requests and use the routines or objects above. I.e. retrieve an HTTP request on a socket, parse it, send back an HTTP response, and then stream data periodically back to the client. Requests that are not "GET" should generate a 501 status code and error return. Malformed requests should generate a 400 status code and response. Requests for URLs that do not equate to streams should generate a 404 status code and response.
• D [15 points]: Take the application above and add the following prototype streams to it. Streams periodically send data back to the client until it disconnects. The streams are: (1) clock - every 1 second, send a line containing the time in "Date" format. The URI for this stream is "/clock", (2) random - every 1 second, send a line containing a random value from 1 to 1000. The URI for this stream is "/random", and (3) uptime - every 1 second, send a line containing the output from the "uptime" command. The URI for this stream is "/uptime".

Notes: Your submissions must at least compile before any credit will be given. Submissions that do not compile will not be graded. Submissions submitted after the due date will not be graded. All work must be your own original work. To get partial credit for parts of the assignment, you must demonstrate that those pieces work by themselves. If you share code with others, you will be given a 0 for the assignment. This assignment set is worth 25% of your total grade.

HTTP 1.0 Specification at http://www.w3.org/pub/WWW/Protocols/HTTP/1.0/spec.html