TCP sockets programming
Here you can find a copy of the source code java files I wrote during last class.
This is the client.
And this is the server code:
Please note that I detailed during the class some DOs and DON'Ts that not necessarily show in my (quick and dirty) code.
This is the client.
import java.net.Socket;
import java.io.*;
import java.util.Scanner;
class TestTCP {
public static void main(String args[]) throws java.net.UnknownHostException, java.io.IOException , java.lang.InterruptedException{
Socket s = new Socket ( "www.upv.es", 80 );
// Thread.sleep(100000);
PrintWriter output = new PrintWriter( s.getOutputStream(), true);
output.println("GET / HTTP/1.0");
output.println("");
Scanner input = new Scanner( s.getInputStream());
while(true) System.out.println(input.nextLine());
}
}
And this is the server code:
import java.net.*;
import java.io.*;
import java.util.Scanner;
class Server {
public static void main(String args[]) throws IOException, InterruptedException{
ServerSocket ss = new ServerSocket(8080);
while(true) {
Socket s = ss.accept();
Scanner input = new Scanner( s.getInputStream());
PrintWriter output = new PrintWriter( s.getOutputStream(), true);
System.out.println(input.nextLine()); // reads a line from the socket (client)
output.println("Hello client!");
s.close();
}
}
}
Please note that I detailed during the class some DOs and DON'Ts that not necessarily show in my (quick and dirty) code.
First assignment is out
You have till December 1st to turn in this first assignment. You may need to have a look to SMTP protocol specification (RFC 821). Please note that this RFC has been obsoleted by newer versions. However, for the purpose of this assignment, the original version of SMTP specs are ok.
Second chapter
Here you have second chapter slides and second lab too.
I know some of you still need to get a valid user account and I'm sorry. While this is not fixed, please ask the lab teacher to pair you with another student with a valid user account so you can do the lab.
I know some of you still need to get a valid user account and I'm sorry. While this is not fixed, please ask the lab teacher to pair you with another student with a valid user account so you can do the lab.
Laboratory starts this week
Just in case you haven't noticed, lab sessions started October 13th. I'm afraid you may be looking for the English version of the lab I forgot to post :-(
1st chapter slides
As I mentioned today in the lecture, here you have the slides from Chapter 1. I have created a Google Docs spreadsheet that will contain all the relevant information about your performance (i.e. class attendance, assignments, etc).
Unfortunately today the service is not working nicely and at the moment I cannot even access that page. As soon as they are back on-line I'll post here the URL for that page.
It is advisable that you check your attendance record from time to time. Please report any error you may find as soon as possible.
Update: Attendance spreadsheet is back on-line.
Update2: Lab calendar is here.
Here we go again
A new course starts on Monday. Amazingly over 25 students are already enrolled on the group, this has to be an all times record for our subject. I want to welcome you all and I hope you'll enjoy the subject.
For the moment I'm only making the course syllabus available. All the slides and interesting materials will be added to this blog little by little. Feel free to go back in time too, but please be warned that links from years ago may no longer be working.
Applied knowledge to physical layer
Most of you are young enough not to have ever used a cassette tape as a digital storage system. But still you may feel curious about how it sounded and, even more important how it worked. This entry links to an article about using software to decode an old BASIC interpreter for Apple I computer.
Different techniques were used long time ago to create audio signals representing digital files that could be stored and recovered from a cassette using an inexpensive cassette player.
And we are back online!!
After one year of using the PoliformaT platform I've got enough. It might well be ok for some people but I'm not among them. I refuse to be a good well-trained monkey.
In what I think is the best interest of my students (and my own sanity) I'm recovering this blog as the vehicle to distribute the class material.
There are a number of reasons for this move:
As an starter I'm posting here the solved exams of last June 9th, 2008.
And the second semester's ...
Please note that older material that is linked from previous entries may not work as it was lost after a hard disk crash. If you absolutely need to get any of them send me an email and I'll recover it for you.
In what I think is the best interest of my students (and my own sanity) I'm recovering this blog as the vehicle to distribute the class material.
There are a number of reasons for this move:
- Students will no longer need to log-in to read any class related news.
- Visitors will now be able to see what's going on in the subject.
- Prospective students will learn what the subject is all about.
- I will be able to avoid to do a dance to upload a single comment or document. However I will have to add a comment with any document I add, which I find appropriated.
- Anyone could comment on the topics of the blog, whether they are enrolled in the subject or not.
- Availability will improve upon university's.
- I will be able to keep the English group of the subject apart from the noise of other languages' groups.
- Blogger's usability is miles away from the ugly and clunky interface of PoliformaT.
- We will be free to enjoy videos of any size (PoliformaT limits to 20 MB max which is a joke).
- Maybe the site will open up collaboration links with other universities.
- Site appearance could easily be changed (if I were not so lazy).
As an starter I'm posting here the solved exams of last June 9th, 2008.
And the second semester's ...
Please note that older material that is linked from previous entries may not work as it was lost after a hard disk crash. If you absolutely need to get any of them send me an email and I'll recover it for you.
Local storage is gone!
After the last storm the computer that used to act as this blog storage server gave up the ghost.
That means that the copies of laboratory exercises and course slides are gone too. Together with many of the documents referenced in this blog. I am not planning on restoring either the contents or the server anytime soon.
However, I will be posting each new document on the "private" PoliformaT site.
That means that the copies of laboratory exercises and course slides are gone too. Together with many of the documents referenced in this blog. I am not planning on restoring either the contents or the server anytime soon.
However, I will be posting each new document on the "private" PoliformaT site.
I have to let this blog go
I want to welcome all the new students. This blog has been the home for the English language class of the subject RED (code 5662). The format was simple (and sometimes even Internet Explorer rendered it properly) and you needed no silly authorization to download anything. However, the UPV in its infinite wisdom has decided to curtail the use of external tools, like this blog, in favor of their locally cooked version of Sakai they have named PoliformaT.
It seems that faculty not using this tool will be considered as doing no work on cyberspace. There is some money involved, don't get me wrong, we have a job to do and some money to make. By putting the carrot on the use of PoliformaT they are insuring all of us will end up using that platform whether it fits our (or your) needs or not.
For our English group it has been a constant cause of trouble the fact that students join us a bit later than the beginning of the term. Because of the involved paperwork, they use to come to the class sooner than they have got a username and password. Under the university instituted systems (so called microwebs and now PoliformaT) they have no access to course syllabus or slides. To address this problem I have been using for two years this blog (the fact blogger interface was cooler and simpler than the local alternatives did help too).
So from here I want to apology in advance for the possible trouble you are facing with this new move at the UPV. While technically I cannot claim this is censorship I would say they are giving as the same choice that Ford Motor Company gave to T-model customers: "You can choose any color you like as long as it is black".
It seems that faculty not using this tool will be considered as doing no work on cyberspace. There is some money involved, don't get me wrong, we have a job to do and some money to make. By putting the carrot on the use of PoliformaT they are insuring all of us will end up using that platform whether it fits our (or your) needs or not.
For our English group it has been a constant cause of trouble the fact that students join us a bit later than the beginning of the term. Because of the involved paperwork, they use to come to the class sooner than they have got a username and password. Under the university instituted systems (so called microwebs and now PoliformaT) they have no access to course syllabus or slides. To address this problem I have been using for two years this blog (the fact blogger interface was cooler and simpler than the local alternatives did help too).
So from here I want to apology in advance for the possible trouble you are facing with this new move at the UPV. While technically I cannot claim this is censorship I would say they are giving as the same choice that Ford Motor Company gave to T-model customers: "You can choose any color you like as long as it is black".
September marks
!!! I am glad to inform you that after marking the exams all of you have passed the subject. Details can be found on the usual place.
Next September 11th
Those of you who haven't pass the subject yet do not forget exam will be held September 11th, at 4:00pm.
Course Marks available
On our usual place in the "exams" tab.
Results are quite disappointing as several people did not show up for the exam. Others did but failed the subject by not scoring good enough. Most of you did pass, for those of you, congratulations.
Those who did not pass the subject, please think whether you could have done better by turning in any of the assignments, showing up for the lectures more often, doing the lab exam and, perhaps, studying a bit more.
Anyway, you are welcome to review your exam so you see for yourself what was wrong. Drop me an email for a reviewing appointment.
Solved exam is now available.
Results are quite disappointing as several people did not show up for the exam. Others did but failed the subject by not scoring good enough. Most of you did pass, for those of you, congratulations.
Those who did not pass the subject, please think whether you could have done better by turning in any of the assignments, showing up for the lectures more often, doing the lab exam and, perhaps, studying a bit more.
Anyway, you are welcome to review your exam so you see for yourself what was wrong. Drop me an email for a reviewing appointment.
Solved exam is now available.
Graded assignments
All the assignments turned in have been graded. Please go to the attendance/marks page to check yours.
Weekend reading
I mentioned today in the class I will post this article on one of the many network security battles. I guess the printer friendly version will remove most of the annoying advertising from the web page (but I was not sure the server would be happy about my referencing of a printer friendly page).
It seems that another one bites the dust in terms of getting their encryption system hacked (not that I am interested or worried as I do not have either content or player for that format).
It seems that another one bites the dust in terms of getting their encryption system hacked (not that I am interested or worried as I do not have either content or player for that format).
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