PHP DATE

The PHP Date() Function

The PHP date() function formats a timestamp to a more readable date and time.
A timestamp is a sequence of characters, denoting the date and/or time at which a certain event occurred.

Syntax

date(format,timestamp)

Parameter	Description
format	Required. Specifies the format of the timestamp
timestamp	Optional. Specifies a timestamp. Default is the current date and time

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PHP Date() - Format the Date

The required format parameter in the date() function specifies how to format the date/time.
Here are some characters that can be used:

• d - Represents the day of the month (01 to 31)
• m - Represents a month (01 to 12)
• Y - Represents a year (in four digits)

A list of all the characters that can be used in the format parameter, can be found in our PHP Date reference.
Other characters, like"/", ".", or "-" can also be inserted between the letters to add additional formatting:

<?php echo date("Y/m/d") . "<br />"; echo date("Y.m.d") . "<br />"; echo date("Y-m-d") ?>

The output of the code above could be something like this:

2009/05/11 2009.05.11 2009-05-11

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PHP Date() - Adding a Timestamp

The optional timestamp parameter in the date() function specifies a timestamp. If you do not specify a timestamp, the current date and time will be used.
The mktime() function returns the Unix timestamp for a date.
The Unix timestamp contains the number of seconds between the Unix Epoch (January 1 1970 00:00:00 GMT) and the time specified.

Syntax for mktime()

mktime(hour,minute,second,month,day,year,is_dst)

To go one day in the future we simply add one to the day argument of mktime():

<?php $tomorrow = mktime(0,0,0,date("m"),date("d")+1,date("Y")); echo "Tomorrow is ".date("Y/m/d", $tomorrow); ?>

The output of the code above could be something like this:

Tomorrow is 2009/05/12

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Complete PHP Date Reference

For a complete reference of all date functions, go to our complete PHP Date Reference.
The reference contains a brief description, and examples of use, for each function!

PHP $_POST

The $_POST Function

The built-in $_POST function is used to collect values from a form sent with method="post".
Information sent from a form with the POST method is invisible to others and has no limits on the amount of information to send.
Note: However, there is an 8 Mb max size for the POST method, by default (can be changed by setting the post_max_size in the php.ini file).

Example

<form action="welcome.php" method="post"> Name: <input type="text" name="fname" /> Age: <input type="text" name="age" /> <input type="submit" /> </form>

When the user clicks the "Submit" button, the URL will look like this:

http://www.w3schools.com/welcome.php

The "welcome.php" file can now use the $_POST function to collect form data (the names of the form fields will automatically be the keys in the $_POST array):

Welcome <?php echo $_POST["fname"]; ?>!<br /> You are <?php echo $_POST["age"]; ?> years old.

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When to use method="post"?

Information sent from a form with the POST method is invisible to others and has no limits on the amount of information to send.
However, because the variables are not displayed in the URL, it is not possible to bookmark the page.

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The PHP $_REQUEST Function

The PHP built-in $_REQUEST function contains the contents of both $_GET, $_POST, and $_COOKIE.
The $_REQUEST function can be used to collect form data sent with both the GET and POST methods.

Example

Welcome <?php echo $_REQUEST["fname"]; ?>!<br /> You are <?php echo $_REQUEST["age"]; ?> years old.

PHP $_GET

The $_GET Function

The built-in $_GET function is used to collect values from a form sent with method="get".
Information sent from a form with the GET method is visible to everyone (it will be displayed in the browser's address bar) and has limits on the amount of information to send.

Example

<form action="welcome.php" method="get"> Name: <input type="text" name="fname" /> Age: <input type="text" name="age" /> <input type="submit" /> </form>

When the user clicks the "Submit" button, the URL sent to the server could look something like this:

http://www.w3schools.com/welcome.php?fname=Peter&age=37

The "welcome.php" file can now use the $_GET function to collect form data (the names of the form fields will automatically be the keys in the $_GET array):

Welcome <?php echo $_GET["fname"]; ?>.<br /> You are <?php echo $_GET["age"]; ?> years old!

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When to use method="get"?

When using method="get" in HTML forms, all variable names and values are displayed in the URL.
Note: This method should not be used when sending passwords or other sensitive information!
However, because the variables are displayed in the URL, it is possible to bookmark the page. This can be useful in some cases.
Note: The get method is not suitable for very large variable values. It should not be used with values exceeding 2000 characters.

PHP FORMS

PHP Form Handling

The most important thing to notice when dealing with HTML forms and PHP is that any form element in an HTML page will automatically be available to your PHP scripts.

Example

The example below contains an HTML form with two input fields and a submit button:

<html> <body> <form action="welcome.php" method="post"> Name: <input type="text" name="fname" /> Age: <input type="text" name="age" /> <input type="submit" /> </form> </body> </html>

When a user fills out the form above and click on the submit button, the form data is sent to a PHP file, called "welcome.php":
"welcome.php" looks like this:

<html> <body> Welcome <?php echo $_POST["fname"]; ?>!<br /> You are <?php echo $_POST["age"]; ?> years old. </body> </html>

Output could be something like this:

Welcome John! You are 28 years old.

The PHP $_GET and $_POST functions will be explained in the next chapters.

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Form Validation

User input should be validated on the browser whenever possible (by client scripts). Browser validation is faster and reduces the server load.
You should consider server validation if the user input will be inserted into a database. A good way to validate a form on the server is to post the form to itself, instead of jumping to a different page. The user will then get the error messages on the same page as the form. This makes it easier to discover the error.

PHP FUNCTION

PHP Functions

In this chapter we will show you how to create your own functions.
To keep the script from being executed when the page loads, you can put it into a function.
A function will be executed by a call to the function.
You may call a function from anywhere within a page.

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Create a PHP Function

A function will be executed by a call to the function.

Syntax

function functionName() { code to be executed; }

PHP function guidelines:

• Give the function a name that reflects what the function does
• The function name can start with a letter or underscore (not a number)

Example

A simple function that writes my name when it is called:

<html> <body> <?php function writeName() { echo "Kai Jim Refsnes"; } echo "My name is "; writeName(); ?> </body> </html>

Output:

My name is Kai Jim Refsnes

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PHP Functions - Adding parameters

To add more functionality to a function, we can add parameters. A parameter is just like a variable.
Parameters are specified after the function name, inside the parentheses.

Example 1

The following example will write different first names, but equal last name:

<html> <body> <?php function writeName($fname) { echo $fname . " Refsnes.<br />"; } echo "My name is "; writeName("Kai Jim"); echo "My sister's name is "; writeName("Hege"); echo "My brother's name is "; writeName("Stale"); ?> </body> </html>

Output:

My name is Kai Jim Refsnes. My sister's name is Hege Refsnes. My brother's name is Stale Refsnes.

Example 2

The following function has two parameters:

<html> <body> <?php function writeName($fname,$punctuation) { echo $fname . " Refsnes" . $punctuation . "<br />"; } echo "My name is "; writeName("Kai Jim","."); echo "My sister's name is "; writeName("Hege","!"); echo "My brother's name is "; writeName("Ståle","?"); ?> </body> </html>

Output:

My name is Kai Jim Refsnes. My sister's name is Hege Refsnes! My brother's name is Ståle Refsnes?

 

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PHP Functions - Return values

To let a function return a value, use the return statement.

Example

<html> <body> <?php function add($x,$y) { $total=$x+$y; return $total; } echo "1 + 16 = " . add(1,16); ?> </body> </html>

Output:

1 + 16 = 17

PHP LOOPING FOR LOOPS

The for Loop

The for loop is used when you know in advance how many times the script should run.

Syntax

for (init; condition; increment)   {   code to be executed;   }

Parameters:

• init: Mostly used to set a counter (but can be any code to be executed once at the beginning of the loop)
• condition: Evaluated for each loop iteration. If it evaluates to TRUE, the loop continues. If it evaluates to FALSE, the loop ends.
• increment: Mostly used to increment a counter (but can be any code to be executed at the end of the loop)

Note: Each of the parameters above can be empty, or have multiple expressions (separated by commas).

Example

The example below defines a loop that starts with i=1. The loop will continue to run as long as i is less than, or equal to 5. i will increase by 1 each time the loop runs:

<html> <body> <?php for ($i=1; $i<=5; $i++)   {   echo "The number is " . $i . "<br />";   } ?> </body> </html>

Output:

The number is 1 The number is 2 The number is 3 The number is 4 The number is 5

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The foreach Loop

The foreach loop is used to loop through arrays.

Syntax

foreach ($array as $value)   {   code to be executed;   }

For every loop iteration, the value of the current array element is assigned to $value (and the array pointer is moved by one) - so on the next loop iteration, you'll be looking at the next array value.

Example

The following example demonstrates a loop that will print the values of the given array:

<html> <body> <?php $x=array("one","two","three"); foreach ($x as $value)   {   echo $value . "<br />";   } ?> </body> </html>

Output:

one two three

PHP SWITCH STATEMENT

The PHP Switch Statement

Use the switch statement to select one of many blocks of code to be executed.

Syntax

switch (n) { case label1:   code to be executed if n=label1;   break; case label2:   code to be executed if n=label2;   break; default:   code to be executed if n is different from both label1 and label2; }

This is how it works: First we have a single expression n (most often a variable), that is evaluated once. The value of the expression is then compared with the values for each case in the structure. If there is a match, the block of code associated with that case is executed. Use break to prevent the code from running into the next case automatically. The default statement is used if no match is found.

Example

<html>
<body>

<?php
switch ($x)
{
case 1:
  echo "Number 1";
  break;
case 2:
  echo "Number 2";
  break;
case 3:
  echo "Number 3";
  break;
default:
  echo "No number between 1 and 3";
}
?>

</body>
</html>

PHP IF ELSE STATEMENT

Conditional statements are used to perform different actions based on different conditions.

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Conditional Statements

Very often when you write code, you want to perform different actions for different decisions.
You can use conditional statements in your code to do this.
In PHP we have the following conditional statements:

• if statement - use this statement to execute some code only if a specified condition is true
• if...else statement - use this statement to execute some code if a condition is true and another code if the condition is false
• if...elseif....else statement - use this statement to select one of several blocks of code to be executed
• switch statement - use this statement to select one of many blocks of code to be executed

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The if Statement

Use the if statement to execute some code only if a specified condition is true.

Syntax

if (condition) code to be executed if condition is true;

The following example will output "Have a nice weekend!" if the current day is Friday:

<html> <body> <?php $d=date("D"); if ($d=="Fri") echo "Have a nice weekend!"; ?> </body> </html>

Notice that there is no ..else.. in this syntax. The code is executed only if the specified condition is true.

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The if...else Statement

Use the if....else statement to execute some code if a condition is true and another code if a condition is false.

Syntax

if (condition)   code to be executed if condition is true; else   code to be executed if condition is false;

Example

The following example will output "Have a nice weekend!" if the current day is Friday, otherwise it will output "Have a nice day!":

<html> <body> <?php $d=date("D"); if ($d=="Fri")   echo "Have a nice weekend!"; else   echo "Have a nice day!"; ?> </body> </html>

If more than one line should be executed if a condition is true/false, the lines should be enclosed within curly braces:

<html> <body> <?php $d=date("D"); if ($d=="Fri")   {   echo "Hello!<br />";   echo "Have a nice weekend!";   echo "See you on Monday!";   } ?> </body> </html>

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The if...elseif....else Statement

Use the if....elseif...else statement to select one of several blocks of code to be executed.

Syntax

if (condition)   code to be executed if condition is true; elseif (condition)   code to be executed if condition is true; else   code to be executed if condition is false;

Example

The following example will output "Have a nice weekend!" if the current day is Friday, and "Have a nice Sunday!" if the current day is Sunday. Otherwise it will output "Have a nice day!":
<html>
<body>

<?php
$d=date("D");
if ($d=="Fri")
  echo "Have a nice weekend!";
elseif ($d=="Sun")
  echo "Have a nice Sunday!";
else
  echo "Have a nice day!";
?>

</body>
</html>

PHP OPERATOR

PHP Operators

This section lists the different operators used in PHP.
Arithmetic Operators

Operator	Description	Example	Result
+	Addition	x=2 x+2	4
-	Subtraction	x=2 5-x	3
*	Multiplication	x=4 x*5	20
/	Division	15/5 5/2	3 2.5
%	Modulus (division remainder)	5%2 10%8 10%2	1 2 0
++	Increment	x=5 x++	x=6
--	Decrement	x=5 x--	x=4

Assignment Operators

Operator	Example	Is The Same As
=	x=y	x=y
+=	x+=y	x=x+y
-=	x-=y	x=x-y
*=	x*=y	x=x*y
/=	x/=y	x=x/y
.=	x.=y	x=x.y
%=	x%=y	x=x%y

Comparison Operators

Operator	Description	Example
==	is equal to	5==8 returns false
!=	is not equal	5!=8 returns true
<>	is not equal	5<>8 returns true
>	is greater than	5>8 returns false
<	is less than	5<8 returns true
>=	is greater than or equal to	5>=8 returns false
<=	is less than or equal to	5<=8 returns true

Logical Operators

Operator	Description	Example
&&	and	x=6 y=3 (x < 10 && y > 1) returns true
||	or	x=6 y=3 (x==5 || y==5) returns false
!	not	x=6 y=3 !(x==y) returns true

PHP STRING VARIABELS

String Variables in PHP

String variables are used for values that contains characters.
In this chapter we are going to look at the most common functions and operators used to manipulate strings in PHP.
After we create a string we can manipulate it. A string can be used directly in a function or it can be stored in a variable.
Below, the PHP script assigns the text "Hello World" to a string variable called $txt:

<?php $txt="Hello World"; echo $txt; ?>

The output of the code above will be:

Hello World

Now, lets try to use some different functions and operators to manipulate the string.

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The Concatenation Operator

There is only one string operator in PHP.
The concatenation operator (.)  is used to put two string values together.
To concatenate two string variables together, use the concatenation operator:

<?php $txt1="Hello World!"; $txt2="What a nice day!"; echo $txt1 . " " . $txt2; ?>

The output of the code above will be:

Hello World! What a nice day!

If we look at the code above you see that we used the concatenation operator two times. This is because we had to insert a third string (a space character), to separate the two strings.

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The strlen() function

The strlen() function is used to return the length of a string.
Let's find the length of a string:

<?php echo strlen("Hello world!"); ?>

The output of the code above will be:

12

The length of a string is often used in loops or other functions, when it is important to know when the string ends. (i.e. in a loop, we would want to stop the loop after the last character in the string).

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The strpos() function

The strpos() function is used to search for character within a string.
If a match is found, this function will return the position of the first match. If no match is found, it will return FALSE.
Let's see if we can find the string "world" in our string:

<?php echo strpos("Hello world!","world"); ?>

The output of the code above will be:

6

The position of the string "world" in our string is position 6. The reason that it is 6 (and not 7), is that the first position in the string is 0, and not 1.

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Complete PHP String Reference

For a complete reference of all string functions, go to our complete PHP String Reference.
The reference contains a brief description, and examples of use, for each function!

PHP VARIABELS

A variable is used to store information.

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Variables in PHP

Variables are used for storing values, like text strings, numbers or arrays.
When a variable is declared, it can be used over and over again in your script.
All variables in PHP start with a $ sign symbol.
The correct way of declaring a variable in PHP:

$var_name = value;

New PHP programmers often forget the $ sign at the beginning of the variable. In that case it will not work.
Let's try creating a variable containing a string, and a variable containing a number:

<?php $txt="Hello World!"; $x=16; ?>

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PHP is a Loosely Typed Language

In PHP, a variable does not need to be declared before adding a value to it.
In the example above, you see that you do not have to tell PHP which data type the variable is.
PHP automatically converts the variable to the correct data type, depending on its value.
In a strongly typed programming language, you have to declare (define) the type and name of the variable before using it.
In PHP, the variable is declared automatically when you use it.

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Naming Rules for Variables

• A variable name must start with a letter or an underscore "_"
• A variable name can only contain alpha-numeric characters and underscores (a-z, A-Z, 0-9, and _ )
• A variable name should not contain spaces. If a variable name is more than one word, it should be separated with an underscore ($my_string), or with capitalization ($myString)

PHP SYNTAK

Basic PHP Syntax

A PHP scripting block always starts with <?php and ends with ?>. A PHP scripting block can be placed anywhere in the document.
On servers with shorthand support enabled you can start a scripting block with <? and end with ?>.
For maximum compatibility, we recommend that you use the standard form (<?php) rather than the shorthand form.

<?php ?>

A PHP file normally contains HTML tags, just like an HTML file, and some PHP scripting code.
Below, we have an example of a simple PHP script which sends the text "Hello World" to the browser:

<html> <body> <?php echo "Hello World"; ?> </body> </html>

Each code line in PHP must end with a semicolon. The semicolon is a separator and is used to distinguish one set of instructions from another.
There are two basic statements to output text with PHP: echo and print. In the example above we have used the echo statement to output the text "Hello World".
Note: The file must have a .php extension. If the file has a .html extension, the PHP code will not be executed.

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Comments in PHP

In PHP, we use // to make a single-line comment or /* and */ to make a large comment block.

<html> <body> <?php //This is a comment /* This is a comment block */ ?> </body> </html>

PHP INSTALL

What do you Need?

If your server supports PHP you don't need to do anything.
Just create some .php files in your web directory, and the server will parse them for you. Because it is free, most web hosts offer PHP support.
However, if your server does not support PHP, you must install PHP.
Here is a link to a good tutorial from PHP.net on how to install PHP5: http://www.php.net/manual/en/install.php

Download PHP

Download PHP for free here: http://www.php.net/downloads.php

Download MySQL Database

Download MySQL for free here: http://www.mysql.com/downloads/

Download Apache Server

Download Apache for free here: http://httpd.apache.org/download.cgi

PHP INTRO

What is PHP?

• PHP stands for PHP: Hypertext Preprocessor
• PHP is a server-side scripting language, like ASP
• PHP scripts are executed on the server
• PHP supports many databases (MySQL, Informix, Oracle, Sybase, Solid, PostgreSQL, Generic ODBC, etc.)
• PHP is an open source software
• PHP is free to download and use

What is a PHP File?

• PHP files can contain text, HTML tags and scripts
• PHP files are returned to the browser as plain HTML 
• PHP files have a file extension of ".php", ".php3", or ".phtml"

What is MySQL?

• MySQL is a database server
• MySQL is ideal for both small and large applications
• MySQL supports standard SQL
• MySQL compiles on a number of platforms
• MySQL is free to download and use

PHP + MySQL

• PHP combined with MySQL are cross-platform (you can develop in Windows and serve on a Unix platform)

Why PHP?

• PHP runs on different platforms (Windows, Linux, Unix, etc.)
• PHP is compatible with almost all servers used today (Apache, IIS, etc.)
• PHP is FREE to download from the official PHP resource: www.php.net
• PHP is easy to learn and runs efficiently on the server side

Where to Start?

To get access to a web server with PHP support, you can:

• Install Apache (or IIS) on your own server, install PHP, and MySQL
• Or find a web hosting plan with PHP and MySQL suppor

Keamanan Jaringan Komputer

Intro
•Computer Security is preventing attackers form achieving objectives through unathorized access or unauthorized use of computers & networks. (John D. Howard,”An analysis Of Security Incidents On The Internet 1989-1995”)
•Jaringan internet bersifat publik
•Arus informasi bisa disadap oleh pihak lain
•Keamanan menjadi useful terhadap kenyamanan jaringan komputer
•Vulnerability suatu jaringan
Network Security Concept
•Tingkat Ancaman (threat) :
1-ingin mengetahui suatu sistem & data pada sebuah jaringan, penyusup disebut the curious
2-Membuat sistem jaringan menjadi down/deface tampilan web, penyusup : the malicious
3-Berusaha untuk menggunakan sumber daya di dalam sistem jaringan komputer untuk memperoleh popularitas, penyusup :the high-profile intruder
•Policy Keamanan (security policy) :
1-Deskripsi secara detail tentang lingkungan teknis, otoritas dalam implementasi sebuah jaringan
2-Analisa resiko yang mengidentifikasi resource dari jaringan, ancaman yang dihadapi
3-Petunjuk bagi administrator sistem untuk mengelola sistem
Hackers Vs Crackers
•Hacker.noun.1. A person who enjoys learning the details of computer systems and know to stretch their capabilities, who prefer to learn only the minimum amount necessary.2. One who programs enthusiastically or who enjoys progamming rather than theorizing about progamming (Guy L. Steele, et al., The Hacker’s Dictionary)
•Istilah yang masih rancu, karena sebagian orang beranggapan hackers mempunyai konotasi positif & sebagian lain mempunyai konotasi negatif
•Batasan tersebut ditentukan etika, moral & integritas dari pelaku sendiri
•Paul Taylor dalam disertasi Phd, mengungkapkan ada 3 (tiga) kelompok, yaitu : Computer Underground (CU), Computer Security Industry (CSI), & kelompok akademis. Sehingga terkadang perbedaan ini menjadi tidak jelas
Example
•Motif pengrusakan/penyusupan berbasis politik, ekonomi & ketenaran
•Serangan hacker portugal mendeface beberapa website milik pemerintah Indonesia, karena tidak setuju dengan yang dilakukan pemerintah di timor-timur
•Serangan hacker Cina & Taiwan terhadap beberapa website Indonesia atas kerusuhan di jakarta ( mei 1998)
Insiden Keamanan Jaringan
•Secara garis besar, dapat diklasifikasikan menjadi :
1.Probe
2.Scan
3.Account Compromize
4.Root Compromize
5.Packet Sniffer
6.Denial Of Service (DoS)
7.Exploitation Of Trust
8.Malicious Code
9.Infrastructure Attacks
In-Depth
•Probe : Usaha yang tak lazim untuk memperoleh akses ke dalam suatu sistem/ untuk menemukan informasi tentang sistem tersebut. Dapat dianalogikan sebagai usaha untuk memasuki sebuah ruangan dengan mencoba-coba apakah pintunya terkunci atau tidak
•Scan : kegiatan probe dalam jumlah besar dengan menggunakan tool secara otomatis. Tool tersebut secara otomatis dapat mengetahui port-port yang terbuka pada host lokal/host remote, IP address yang aktif bahkan bisa untuk mengetahui sistem operasi yang digunakan pada host yang dituju
next
•Account Compromise : penggunaan account sebuah komputer secara ilegal oleh seseorang yang bukan pemilik account tersebut. Account Compromise dapat mengakibatkan korban mengalami kehilangan atau kerusakan data.
•Root Compromise : mirip dengan account compromise, dengan perbedaan account yang digunakan secara ilegal adalah account yang mempunyai privelege sebagai administrator sistem. Akibat yang ditimbulkan bisa mengubah kinerja sistem, menjalankan program yang tidak sah
Next
•Packet Sniffer : program yang dapat digunakan untuk menyadap data & informasi melalui jaringan komputer. Di tangan seorang admin, program sniffer sangat bermanfaat untuk mencari (debug) kesalahan jaringan/memantau adanya serangan. Mode promiscuous “mendengar” semua traffic yang sedang berjalan
•Denial of Service (Dos) merupakan sebuah usaha (dalam bentuk serangan) untuk melumpuhkan sistem yang dijadikan target sehingga sistem tersebut tidak dapat menyediakan servis-servisnya atau tingkat servis menurun dengan drastis. Sistem yang diserang dapat menjadi “bengong” (hang, crash), turun kinerjanya (beban CPU tinggi)
next
•Eksploitasi Terhadap kepercayaan : pemerolehan akses komputer secara legal dengan memanfaatkan identitas yang samar
•Malicious Code : suatu program yang bila dieksekusi akan menyebabkan sesuatu yang tidak diinginkan di dalam user, yang termasuk malicious code : trojan horse, virus & worm.
Worm : program yang dapat menduplikasi diri dan menyebar tanpa intervensi manusia setelah program tersebut dijalankan
Trojan Horse : program yang disisipkn tanpa pengetahuan si pemilik komputer, dapat dikendalikan dari jarak jauh & memakai timer

Sharing Internet untuk 2 PC dengan Bridge Windows

Tutorial Jaringan kali ini erat sekali hubungannya dengan tutorial penulis sebelumnya, yakni mengenai “Koneksi 2 PC menggunakan kabel Cross”, sehingga sebelum membaca artikel ini lebih lanjut, penulis sarankan untuk membaca artikel tersebut.
Bagi seorang yang memiliki akses internet di rumah mungkin pernah menemui kasus seperti bagaimana caranya membagi koneksi internet hanya untuk 2 pc. Bisa saja menggunakan switch atau hub, kemudian memasangkan kabel modem adsl ke dalam switch atau hub tersebut kemudian membagi koneksi berdasarkan topologi jaringan star. Penulis rasa ini hanya menghabiskan resource saja, dan dana yang keluar tentunya lebih besar lagi. Kira-kira gambarannya adalah seperti ini :

Dibutuhkan satu buah switch, sekitar beberapa minggu yang lalu penulis cek harga hub 8 port itu sekitar Rp 250 ribu. , dan dibutuhkan 2 kabel jenis strike, di tambah 4 buah RJ 45, hmmm... berapa kira-kira dana yang habis di keluarkan ?? Kurang lebih sekitar Rp 270 ribu.   Mungkin bisa kurang. Tergantung yang jual temen atau bukan. Harga temen sekitar ... Lah jadi jualan ?? ~~
Beda halnya jika kita menggunakan topologi bus yang hanya membutuhkan satu buah lan card tambahan, dipasang pada salah satu pc, dan satu buah kabel jenis cross, tentunya bisa meminimalisir biaya yang akan dikeluarkan, satu buah lan card harganya sekitar Rp 45 ribu. Sisanya bisa dipakai untuk pedi cure dan medi cure ... ~~  Ya, kira-kira gambaran dari topologi bus yang dapat meminimalisir pengeluaran, seperti ini :

Hanya dibutuhkan satu buah lancard tambahan, dan satu buah kabel cross. Lan card tambahan dipasang di salah satu pc, dan pc ini harus terhubung secara langsung ke modem adsl, seperti pada gambar di atas. Dengan kata lain, 2 lan card inilah yang nantinya akan dijadikan sebagai bridge. Perlu diketahui bridge dalam windows XP biasanya hanya memiliki satu alamat IP.
Penulis tegaskan kembali, teknik yang satu ini berbeda dengan teknik ketika anda membuat dial connection type PPoE (biasanya digunakan pada broadband ADSL). Dial connection langsung dari PC berakibat  pc yang mendial connection tersebut akan memiliki IP Public. Nah itu adalah alasan penulis membuat artikel ini. Dengan kata lain, pada teknik ini yang memiliki ip public nantinya adalah si modem itu sendiri. Bukan PC yang melakukan Dialing connection. PC di sini hanya berfungsi sebagai bridge saja. Bukan mendial connection.
Setelah terpasang jaringan seperti pada gambar, langkah selanjutnya adalah menyetting komputer yang memiliki 2 lan card tersebut.
1.    Klik Start > Run > ketik Regedit [enter]
2.    Masuk ke : HKEY_LOCAL_MACHINESYSTEMCurrentControlSetServicesTcpipParameters
3.    Ubahlah Nilai dari “IPEnableRouter” menjadi 1
4.    Tutup Regedit.
5.    Restart PC.
Langkah selanjutnya adalah membuat bridge dari 2 LAN Card pada pc tersebut. Caranya adalah, masuk ke Control Panel ? Network Connection, kemudian klik kanan dan pilih bridge connection.

Tunggu sebentar hingga terdapat 1 koneksi baru, yaitu network bridge.

Kemudian klik kanan Network Bridge tersebut, pilih properties, pada adapters centang 2 lancard yang akan dijadikan bridge,

pada This Connection Use the following items, pilih Internet Protocol (TCP/IP) kemudian klik button Properties. Untuk pengisian IP Address, di haruskan 1 class dengan modem adsl, pada gambar ini terlihat, PC yang di jadikan Bridge mempunyai IP, 192.168.1.2, dan Modem ADSL sebagai Gatewaynya adalah 192.168.1.1, Preferres DNS server di sini adalah DNS milik ISP.

Selesai kemudian Ok.
Selanjutnya adalah settingan pada client, yakni di haruskan untuk menggunakan IP Class yang sama dengna bridge, anda bisa menggunakan 192.168.1.3 – 192.168.1.254, dengan Default Gatewaynya mengarah kepada Bridge, yakni 192.168.1.2, dan DNS Server mirip dengan propertiesnya bridge. Ya, selesai, anda sudah dapat menggunakan fasilitas bridge ini untuk berinternet ria.
Terima Kasih.
Greetz : b_scorpio, abuzahra, peterpanz, kandar, phii_, syahrilrohman, ivan, dr.emi, safril, hg_, rux, d2n, dent_, minangmedia, riezno, Lapak-online Team!

aktifakn proxy IE

 

Written by lirva32    Thursday, 23 August 2007

Hidden Your IP Before Hacking
-- biar kagak ketangkep kalo mau iseng2...

author : lirva32 [at] yahoo [dot] com

Hiikksss..beberapa menit yang lalu (--sekarang sih pukul 23.13) ketika gue asik ngoprek bluetooth hacking dengan SuSe... tiba2 saja HP gue berdering.. ternyata sahabat gue 'sang hacker' menelpon dan menyampaikan pesan bahwa malam ini mau melakukan proses defacing terhadap salah 1 (satu) situs underground, tak ayal lagi gue pun langsung mengaktifkan router ADSL... konek... dan menuju situs target... gue hanya melihat2 bak melihat jam tangan casio di etalase... tidak melakukan penetrasi test apapun...gue tidak mengetahui lubangya ada dimana... karena memang sudah lama sekali gue meninggalkan kegitan defacing...;). Rasa penasaran dan iseng menghujani fikiran gue yang memang hari ini masih kotor terkena deburan debu. Stttoooppppp...!!!!
Untung saja dalam setiap aksi gue selalu menutupi dan memalsukan IP address yang gue gunakan (-- sekalipun terkadang lupa..;) jadi sekarang gue akan membahas tentang cara menyembunyikan IP Address saat browsing di Internet dengan menggunakan bantuan anonymous web proxy. Ini dilakukan agar IP Address asli yang digunakan tidak diketahui oleh remote web server.

Ada berapa alasan mengapa kita harus menyembunyikan dan memalsukan IP Address asli yang kita miliki, antara lain:
[+] Mengakses ke website yang melakukan restriction -- hanya membolehkan akses dari IP Address tertentu saja.
[+] Privasi, karena gue 'ga mau nanti IP gue jadi IP tersangka.
[+] Menghindari pelacakan jika kita melakukan tindakan yang 'tidak seharusnya kita lakukan'. (baca: hacking) :-)

------| Menggunakan Proxy

Dalam melangsungkan sebuah proses attack, sebaiknya seorang attacker melakukan beberapa pengamanan. Umumnya yang dilakukan adalah:
[+] Menghapus log files pada victim
[+] Menyembunyikan IP Address komputer yang digunakan untuk melangsungkan attack
[+] Melakukan modifikasi minimum untuk tidak menarik perhatian pemilik system seperti tidak menambah user atau membuat direktori yang terlalu 'vulgar'

Penggunaa proxy disesuaikan dengan program yang kita gunakan untuk melakukan browsing seperti Internet Explorer, Mozilla, Opera, mIRC, dan lain-lain.

------|Sample: Internet Explorer

1. Jalankan Internet Explorer (IE)
2. Klik Tools
3. Klik Internet Option
4. Klik Connections
5. Klik LAN Settings
6. Aktifkan option 'Use a proxy server'

------|Sample: wget

1. Edit file /etc/wgetrc atau ~/.wgetrc
2. Ubah atau tambahkan baris : http_proxy=http://ip_address_proxy:port/

------|Sample: libwww-perl (LWP)

Pada source code program yang menggunakan bahasa pemrograman Perl dapat ditambahkan:

$ua->proxy(['http', 'ftp'], 'http://ip_address_proxy:port/');

Cara lain adalah dengan meload proxy setting dari *_proxy environment variables.

$ua->env_proxy

Untuk mengubah environment variables, dapat dilakukan via command line:

$ export http_proxy=http://ip_address_proxy:port/	(sh/bash/ksh)
% setenv http_proxy 'http://127.0.0.1:8080/'	(csh/tcsh)

------|Proxy Testing

Jika semuanya berjalan lancar maka kita dapat melakukan browsing secara anonymous. Lihat bagian appendix untuk mendapatkan contoh anonymous proxy.
Untuk mengetahui apakah IP Address asli yang kita gunakan sudah tersembunyi dan digantikan oleh IP Address milik anonymous web proxy, kita dapat melakukan pengecekan dengan melakukan browsing ke website yang memiliki fitur browser checker seperti
* www.dnsstuff.com
* noc.cbn.net.id
* dan lain-lain

------| Anonymity

Beberapa istilah yang berkaitan dengan anonymous proxy:

* Anonymous - HTTP proxy server tidak mengirimkan variable HTTP_X_FORWARDED_FOR kepada remote host, hal diini dilakukan untuk menyembunyikan IP Address asli kita.

* High anonymity (elite proxy) - HTTP proxy server jenis ini tidak mengirimkan variable HTTP_X_FORWARDED_FOR, HTTP_VIA dan HTTP_PROXY_CONNECTION.

Apa yang membedakan anonymous proxy dan elite proxy adalah pengiriman variable HTTP_* oleh proxy server. Pada anonymous proxy, sangat dimungkinkan bagi remote host untuk mengetahui IP Address asli yang kita miliki dengan melihat variable HTTP_VIA dan HTTP_PROXY_CONNECTION.

Kalau Anda males cari2 anonymous proxy... ya sudah, lirva32 akan kasih tau beberapa tools yang memang cukup handal untuk membuat diri kita aman.
Tools2nya rata2 bayar sih...juga berbasis window$... tapi lirva32 akan mengangap.. dan selalu mengangap... kalo tools itu 'warez'.... Viva Wares... Happy Warez..., diantaranya :

-                                                     Steganos : Internet Anonym -
kalo tools yang ini gue sering pake banget ketika melakukan tindakan anarkis... gue ga usah pusing2
cari2 IP Proxy... bisa destroy tracing dan shredder lagi... keeyeeenn ddeehhh ;)

--------------------------------------------------------------------------------------------

- Hide IP Platinum -
lebih ringan.. lebih cepet.. banyak IP yang bisa digunakan untuk pemalsuan ;)

--------------------------------------------------------------------------------------------

- GhostSurf Platinum -
sama saja... biasa saja... tidak ada yang spesial... tapi tetap mumpuni...;)

--------------------------------------------------------------------------------------------

------|Appendix : Daftar Anonymous Proxy

Semoga bermanfaat.. maaf, kalo tulisan yang gue buat terlalu kiddies.. krn memang gue kiddies.... lol

.thx
lirva32

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