An IP address (Internet Protocol address) is a unique address that certain electronic devices currently use in order to identify and communicate with each other on a computer network utilizing the Internet Protocol standard (IP)—in simpler terms, a computer address. Any participating network device—including routers, switches, computers, infrastructure servers (e.g., NTP, DNS, DHCP, SNMP, etc.), printers, Internet fax machines, and some telephones—can have its own address that is unique within the scope of the specific network. Some IP addresses are intended to be unique within the scope of the global Internet, while others need to be unique only within the scope of an enterprise.
The IP address acts as a locator for one IP device to find another and interact with it. It is not intended, however, to act as an identifier that always uniquely identifies a particular device. In current practice, an IP address is less likely to be an identifier, due to technologies such as Dynamic assignment and Network address translation.
What are IP Addresses
Web Proxies
In computer networks, a proxy server is a server (a computer system or an application program) which services the requests of its clients by forwarding requests to other servers. A client connects to the proxy server, requesting some service, such as a file, connection, web page, or other resource, available from a different server. The proxy server provides the resource by connecting to the specified server and requesting the service on behalf of the client. A proxy server may optionally alter the client’s request or the server’s response, and sometimes it may serve the request without contacting the specified server. In this case, it would ‘cache’ the first request to the remote server, so it could save the information for later, and make everything as fast as possible.
A proxy server that passes all requests and replies unmodified is usually called a gateway or sometimes tunneling proxy.
A proxy server can be placed in the user’s local computer or at specific key points between the user and the destination servers or the Internet.
Caching proxy server
A proxy server can service requests without contacting the specified server, by retrieving content saved from a previous request, made by the same client or even other clients. This is called caching. Caching proxies keep local copies of frequently requested resources, allowing large organizations and Internet Service Providers to significantly reduce their upstream bandwidth usage and cost, while significantly increasing performance. There are well-defined rules for caching. Some poorly-implemented caching proxies have had downsides (e.g., an inability to use user authentication). Some problems are described in RFC 3143 (Known HTTP Proxy/Caching Problems).
Web proxy
Proxies that focus on WWW traffic are called web proxies. Many web proxies attempt to block offensive web content. Other web proxies reformat web pages for a specific purpose or audience (e.g., cell phones and PDAs)
Access control: Some proxy servers implement a logon requirement. In large organizations, authorized users must log on to gain access to the ‘WWW.’ . The organization can thereby track usage to individuals.
Anonymizing proxy server
A proxy server that removes identifying information from the client’s requests for the purpose of anonymity is called an anonymizing proxy server or anonymizer.
Transparent and non-transparent proxy server
The term “transparent proxy” is most often used incorrectly to mean “intercepting proxy” (because the client does not need to configure a proxy and cannot directly detect that its requests are being proxied).
However, RFC 2616 (Hypertext Transfer Protocol — HTTP/1.1) offers different definitions:
“A ‘transparent proxy’ is a proxy that does not modify the request or response beyond what is required for proxy authentication and identification.
“A ‘non-transparent proxy’ is a proxy that modifies the request or response in order to provide some added service to the user agent, such as group annotation services, media type transformation, protocol reduction, or anonymity filtering.”
Renaming Win XP Start Menu Button
This guide will show you how to edit/rename the Windows XP start menu button.Are you bored of having the name “start”? If so now you can rename your start menu button to give the name of your choice.
STEP 1:BYPASSING WINDOWS FILE PROTECTION
1.Launch My Computer,click tools,folder options,then view
2.Select show all hidden files and folders option and uncheck the option hide
protected operating system files,unckeck hide extention for known file types
3.Open C:\windows\system32\restore,select the file filelist.xml,right click it go to properties and uncheck read-only
4.Open it(filelist.xml) with notepad
5.Add the line <rec>%systemroot%\explorer.exe</rec> as shown below
<exclude>
<rec>%systemroot%\explorer.exe</rec>
<rec> %windir%\system.ini</rec>
<rec> %windir%\tasks\desktop.ini</rec>
<rec> %windir%\win.ini</rec>
<rec> *:\AUTOEXEC.BAT </rec>
<rec>*:\CONFIG.MSI</rec>
<rec> *:\CONFIG.SYS </rec>
6.Save the file
7.Open C:\windows\system32\dllcache,you will find a backup copy of explorer.exe. Rename it to explorer.bak.
STEP 2:CHANGING THE NAME OF START BUTTON
1.Open Resource Hacker,open C:\windows\explorer.exe
2.Expand string,expand 37,click on 1033
3.On right side raname “start” to anything you want EG.”anything” and press compile script
4.Repeat the same procedure for string,38,1033
5.Save changes in file menu(if error occurs close explorer.exe and repeat sub-step 3 & 4
6.Press ctrl+alt+del in processes tab of task manager endtask explorer.exe
7.Again in new task open C:\windows\explorer.exe you will see that start menu is renamed
8.Close task manager and ENJOY!!!!
Program to Print it’s Own Source Code
#include
char *program=”#include
program=%c%s%c;%cvoid main()%c{%cprintf
(program,10,34,program,34,10, 10,10,10);%c}”;
void main()
{
printf(program,10,34,program,34,10,10,10,10);
}
C Program to Remove Comments and Blank lines from a valid C Program
#include
#include
#include
#include
void main()
{
FILE *a,*b;
char fname[20],ch,tch=NULL,tch1=NULL;
int flag1=0,flag=0,count=0,count1=0,count2=0;
clrscr();
printf(”Enter the file name (.C or .TXT)\n”);
gets(fname);
a=fopen(fname,”r”);
if(a==NULL)
{
puts(”Cannot open the source file!!!”);
delay(500);
exit(1);
}
b=fopen(”target.c”,”w”);
if(b==NULL)
{
puts(”Cannot create target file!!!”);
delay(500);
exit(1);
}
while(1)
{
ch=fgetc(a);
if(ch==EOF) break;
else
{
if(ch==’\n’)
{
count1=1;
tch1=ch;
continue;
}
else if(ch==’\n’&& count1==1)
continue;
else if(ch==’/'&&count==0)
{
flag1=1;
tch=ch;
count=1;
continue;
}
else if(ch==’*'&& flag1==1)
{
flag=1;
flag1=0;
tch=NULL;
}
else if(ch==’*'&&flag==1)
{
count2=1;
count=1;
continue;
}
else if(ch==’/'&&count2==1)
{
flag=0;
count=0;
tch=NULL;
continue;
}
else if(count==1&&flag==1)
count=0;
else if(flag1==1)
flag1=0;
}
if(flag!=1)
{
if(tch>0)
fputc(tch,b);
if(tch1>0)
fputc(tch1,b);
tch1=NULL;
tch=NULL;
count=0,count1=0,count2=0;
fputc(ch,b);
flag1=0,flag=0;
}
}
puts(”DONE!! OP FILE IS \”TARGET.C\”\n”);
fcloseall();
getch();
}
Activating the hidden Boot Screen in Vista
Although this feature never made it into the released version of Windows Vista, there appears to be some parts of it left in the system. This section shows you a cool trick that will enable a hidden boot screen that looks like it was part of the high-resolution feature, as shown in Figure 1-1. It is nothing super fancy or elegant, but it sure is better than the boring boot screen that Vista shipped with, which looks like it is missing the Vista logo.
Figure 1-1
- Click the Start button, type msconfig in the Search box, and then press Enter.
- When the System Configuration Utility loads, click the Boot tab.
- Locate the No GUI boot box and select it, as shown in Figure 1-2.
Figure 1-2.
4. Click OK and reboot your computer.
You should see the hidden boot screen after you reboot your PC. As I mentioned earlier, if you have problems with the hidden boot screen, just boot into Safe mode (hold down F8 when you boot up) and remove the check from the No GUI Boot box.
Customizing the boot screen image
The alternative boot screen that you just enabled in the preceding section is a great improvement compared to the boring moving progress bar that shows by default. However, this is still not good enough. With the help of a few cool tricks, you can create your own high-resolution, 24-bit boot screen without hacking any system files.
How is that possible? Thanks to the new language-independent operating system components in Windows Vista, some resources are stored in regional language files rather than the actual system components. This allows Microsoft to easily create a localized version of Windows Vista in any language by just creating new MUI (multilingual user interface) files that contain localized versions of bitmaps and text. Because MUI files are not digitally signed by Microsoft, you can make your own that has your own boot screen image in it, which allows you to customize the alternative boot screen to use any image you desire.
This new feature in Windows Vista provides a great enhancement and alternative to the traditional method of hacking system files as you had to do in previous versions of Windows to do things such as changing the boot screen. In addition, there is a great tool developed by Dan Smith called the Vista Boot Logo Generator that will automatically compile the boot images you select into an MUI file. This makes the overall process simple compared to trying to change boot screens, as you did in the past.
To get started, you need two images, one 800 × 600 and one 1024 × 768 image, both saved as 24-bit bitmap images. When you have those images picked out, resized, and saved, you are ready to follow these steps:
- Visit http://www.computa.co.uk/staff/dan/?p=18 and download the latest copy of the Vista Boot Logo Generator and install it.
- Click the Start button, type vista boot logo, and press Enter.
- After the boot logo is downloaded, click the Browse for Images button in the 800 × 600 section and select your 800 × 600 24-bit bitmap image. Do the same for the 1024 × 768 section.
- After you have both images selected, click File and select Save Boot Screen file as to save your MUI file. Save it to your desktop.
- Next you need to replace the winload.exe.mui file located in c:\windows\system32\en-us with the file you just created. However, it is not as easy as a simple copy and paste because the Windows system files are protected. First, I recommend making a backup of the existing winload.exe.mui file so that you can copy it back if you have problems later. To get around the file protections, you need to take ownership of all the files in the en-us folder. Right-click the en-us folder and select Properties.
- Select the Security tab and then click the Advanced button at the bottom of the window.
- Select the Owner tab, and then click the Edit button.
- Select your account from the Account list and check Replace owner on subcontainers and objects. Click OK to apply your changes.
- Click OK to exit all the open Properties windows. You need to go back into the folder properties to change the file permissions. This time you will have more rights because you are now the folder owner. Right-click en-us and select Properties again.
- Click the Security tab, and this time click Edit.
- Click the Add button. Type in your username and click OK. Your account name should now appear on the Permissions list.
- Select your account, and then select the Allow column for Full control, as shown in Figure 1-3.
Figure 1-3.
Click OK to save your changes and OK once more to close the Properties screen. You will now be able to copy the winload.exe.mui file you made and saved to your desktop to c:\windows\system32\en-us. After you copy the file and reboot, you should see your new boot screen.
If you do not see your new boot screen and instead see the progress bar, make sure that you turned on the alternative boot screen as shown in the previous section. If you have any problems with your new boot screen MUI file, you can always boot using your Windows Vista install CD into a command prompt and can copy back the old winload.exe.mui file.
C Program To Print A String Without Using Any Output Statements
#include
#include
char str[]=”Hello Srikanth”;
char far *v=(char far *)0xb8000000;
void main()
{
int i;
for(i=0;i<14;i++)
{
*v=str[i];
v+=2;
}
getch();
}
