Anonymity of a Proxy Server Explained

Sharan R >> , ,
How does Proxy Server Works ?
This is the First Question that arises in our mind when we use the Proxy Servers for Surfing the Internet without revealing our Identity to Others. Here all these mindboggling questions are answered with easy to understand examples.
The exchange of information in Internet is made by the “client - server” model. A client sends a request (what files he needs) and a server sends a reply (required files). For close cooperation (full understanding) between a client and a server the client sends additional information about itself: a version and a name of an operating system, configuration of a browser (including its name and version) etc.

This information can be necessary for the server in order to know which web-page should be given (open) to the client. There are different variants of web-pages for different configurations of browsers. However, as long as web-pages do not usually depend on browsers, it makes sense to hide this information from the web-server.

What your browser transmits to a web-server:
  • name and a version of an operating system
  • name and a version of a browser
  • configuration of a browser (display resolution, color depth, java / javascript support, …)
  • IP-address of a client
  • Other information

The most important part of such information (and absolutely needless for a web-server) is information about IP-address. Using your IP it is possible to know about you the following:
  • country where you are from
  • city
  • your provider?s name and e-mail
  • your physical address

Information, transmitted by a client to a server is available (accessible) for a server as environment variables. Every information unit is a value of some variable. If any information unit is not transmitted, then corresponding variable will be empty (its value will be undetermined).

These are some environment variables:
REMOTE_ADDR ? IP address of a client

HTTP_VIA ? if it is not empty, then a proxy is used. Value is an address (or several addresses) of a proxy server, this variable is added by a proxy server itself if you use one.

HTTP_X_FORWARDED_FOR ? if it is not empty, then a proxy is used. Value is a real IP address of a client (your IP), this variable is also added by a proxy server if you use one.

HTTP_ACCEPT_LANGUAGE ? what language is used in browser (what language a page should be displayed in)

HTTP_USER_AGENT ? so called “a user?s agent”. For all browsers this is Mozilla. Furthermore, browser?s name and version (e.g. MSIE 5.5) and an operating system (e.g. Windows 98) is also mentioned here.

HTTP_HOST ? is a web server?s name
This is a small part of environment variables. In fact there are much more of them (DOCUMENT_ROOT, HTTP_ACCEPT_ENCODING, HTTP_CACHE_CONTROL, HTTP_CONNECTION, SERVER_ADDR, SERVER_SOFTWARE, SERVER_PROTOCOL, …). Their quantity can depend on settings of both a server and a client.

[eminimall]
These are examples of variable values:
REMOTE_ADDR = 194.85.1.1
HTTP_ACCEPT_LANGUAGE = ru
HTTP_USER_AGENT = Mozilla/4.0 (compatible; MSIE 5.0; Windows 98)
HTTP_HOST = www.webserver.ru
HTTP_VIA = 194.85.1.1 (Squid/2.4.STABLE7)
HTTP_X_FORWARDED_FOR = 194.115.5.5

Anonymity at work in Internet is determined by what environment variables “hide” from a web-server.
If a proxy server is not used, then environment variables look in the following way:
REMOTE_ADDR = your IP
HTTP_VIA = not determined
HTTP_X_FORWARDED_FOR = not determined

According to how environment variables “hided” by proxy servers, there are several types of proxies

Transparent Proxies
They do not hide information about your IP address:
REMOTE_ADDR = proxy IP
HTTP_VIA = proxy IP
HTTP_X_FORWARDED_FOR = your IP

The function of such proxy servers is not the improvement of your anonymity in Internet. Their purpose is information cashing, organization of joint access to Internet of several computers, etc.

Anonymous Proxies
All proxy servers, that hide a client?s IP address in any way are called anonymous proxies

Simple Anonymous Proxies

These proxy servers do not hide a fact that a proxy is used, however they replace your IP with its own:
REMOTE_ADDR = proxy IP
HTTP_VIA = proxy IP
HTTP_X_FORWARDED_FOR = proxy IP
These proxies are the most widespread among other anonymous proxy servers.

Distorting Proxies

As well as simple anonymous proxy servers these proxies do not hide the fact that a proxy server is used. However a client?s IP address (your IP address) is replaced with another (arbitrary, random) IP:
REMOTE_ADDR = proxy IP
HTTP_VIA = proxy IP
HTTP_X_FORWARDED_FOR = random IP address

High Anonymity Proxies

These proxy servers are also called “high anonymity proxy”. In contrast to other types of anonymity proxy servers they hide a fact of using a proxy:
REMOTE_ADDR = proxy IP
HTTP_VIA = not determined
HTTP_X_FORWARDED_FOR = not determined
That means that values of variables are the same as if proxy is not used, with the exception of one very important thing ? proxy IP is used instead of your IP address.

Summary
Depending on purposes there are transparent and anonymity proxies. However, remember, using proxy servers you hide only your IP from a web-server, but other information (about browser configuration) is accessible!
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What Is PPPoE and bridge mode of ADSL Modem

Sharan R >> , ,
There are two ways to configure an ADSL modem for broadband connection. One in PPPoE (Point to Point Protocol over Ethernet) and the another is Bridge mode.

1.PPPoE Mode


In this mode the modem works as router and the PPPoE session terminates on WAN port of router. The PPPoE client is in built in the modem and allocated by BRAS server gets assigned to WAN port of modem. The Internal network has to use the private IP and for Internet access NATing happens in modem. In PPPoE mode the modem is configured in such a way that the user id and password are stored inside the Modem. Internet connection will be established as you switch on the Modem.

 
 
PPPoE Mode
 
2.Bridge Mode

In this mode the modem works as transparent Ethernet bridge and therefore you need to run the PPPoE client software ( for login authentication) on your PC/server. WIN XP systems have this feature inbuilt but for other operating systems you need to buy it from market. Some freeware like RASPPPoE, Enternet etc. are also available on the Internet.

bridge mode

Both the modes can be used as per the requirement and application. Here enumerating the main differences

PPPoE mode

1. User id and password stored inside the Modem.
2. Multiple PCs can be connected. For example most of the basic ADSL Modems having at least one ADSL port and one USB port. In PPPoE mode, can connect one PC to Ethernet port and one PC to USB port which enable simultaneous internet usage in both the PCs.
3. PPPoE mode is more secured.
4. For Torrents download, appropriate ports need to be forwarded.

Bridge Mode

1. In bridge mode user id and password to be entered in the dialer of computer.
2. Only single PC can be connected.
3. For torrents download port forwarding is not required.
4. Less secured because all the ports are open need good firewall to avoid virus infection.
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Trace Network Information Using Command Prompt

Sharan R >> , ,
There are many applications that claim to help network administrators to trace, diagnose and resolve network related issue.

However, I strongly believe that knowing your basics is always the key to success. Therefore, knowledge of performing simple tasks such as checking the latency of your connection and tracing a route is essential for network professionals.

In this article I will tell you how to trace network related information using command prompt commands.


Tracert and netstat are command line names that are enough to scare any user from using the command prompt. Nonetheless, such command are still widely used by network and system administrators to diagnose and resolve some very important network related issue.

Tracert

The path between two computers connected via the internet cannot be defined as a straight line.
It consists of numerous “hops” from one intermediate computer to another.

Tracert or traceroute is a command that shows the time taken for each hop and the IP address for each intermediary computer (as shown below).

An example of a tracert command would be something like: tracert google.com. You can also use the IP address instead of the hostname to use the tracert command. This command is used to see a network packet being sent and received and the amount of hops required for that packet to get to its destination. You can use tracert to determine where a packet stopped on the network. This can allow network professionals to establish if there is a router configuration problem.



Netstat shows the active TCP connections and ports for a computer, Ethernet statistics, the IP routing table, statistics for the IP, ICMP(Internet Control Message Protocol), TCP(Transmission Control Protocol), and UDP(User Datagram Protocol) protocols.

One possible use for Netstat is to determine if a malware may have established connections that you might be unaware of. If you type netstat /? And hit enter in your command prompt, you will be able to see details regarding a list of netstat commands.

For example nestat:
-a displays all connections.
-b displays the executable involved in creating each connection.
-e displays Ethernet statistics.
-f displays the FQDN (Fully Qualified Domain Name) for foreign addresses.
-n displays active TCP connections (addresses and port numbers are expressed numerically).
-p proto shows connections for the protocol specified by Proto.
- r displays the routing table.
-s displays the per protocol statistics.
-t displays the current connection offload state.
interval re-displays selected statistics, pausing interval seconds between each display.

For more information simply use the netstat /? command.



Commands like netstat and tracert are by no means obsolete and will be used for many years to come.

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Create A Quick Ad Hoc Wireless Network Connection Between Two Computers In Windows 7/Vista

Sharan R >> , , , ,

Do you want to create a quick network connection between two computers or laptops to share some files?

Or maybe you want to share an internet connection? Windows 7 and Vista have a build-in feature to create a quick ad hoc wireless network connection, this means you can connect directly with another computer or laptop without the need of a router.


To begin, click Start and select Network. Now click on Network And Sharing Center as shown in the screenshot below. If you can’t find Network, then type Network in Start Search and hit Enter.

icon of network connection

Now in the left sidebar, click Set Up A Connection Or Network. From the list select Set Up A Wireless Ad Hoc(Computer-To-Computer) Network option and click Next.

set up wireless ad hoc network connection

Click Next again and it will ask you to type a Network name and select the Security settings as shown in the screenshot below.

network name and security coptions

Make sure you select a good password, if you don’t know which security type to select, click on Help Me Choose link next to it. After you are done click Next and the Network connection will be ready.
Now in the Network And Sharing Center you can choose what to share as you can see from the screenshot below.

sharing and discovery

To Share an Internet Connection, click View Status next to the connection that you want to share. Now click on Properties button which you will find under Activity.

Click on the Sharing tab and tick the checkbox where it says Allow Other Network Computers To Connect Through This Computer’s Internet Connection. Under Home Networking Connection select Wireless network Connection and click OK.

network connection sharing properties

Now your connection is ready to to shared. To enable the wireless network connection you just made, go to Start and click Connect To.

connect to a network

You will see your wireless connection listed there. Select your connection and click Connect.

wireless network connection

You will see a success message as shown below.

Wireless is ready to be used

You will see your connection listed under Wireless Network Connection on the other computer. Simply connect from there and you are done sharing the internet connection.

Note: To connect successfully make sure the wireless hardware is enabled on both computers or laptops.

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How To Share Internet Connection With Another Computer Using Windows 7/Vista

Sharan R >> , , , ,
Having two computers at your home, you may have only one internet connection which you want to share between two computers.
Now consider there are two computers. Computer A has Windows Vista while computer B has Windows XP. Computer A is connected to internet via cable (so this will be connected through LAN card). Now to connect to Computer B, you will need another LAN card (to connect to more than one computer, you will need a wired hub).

First, Let us connect two computers in LAN

Follow these steps to connect two computers in LAN.

Step 1: In Windows 7/Vista, you should enable Sharing and Discovery before doing that. You can do this by going to Control Panel > Network and Sharing Centre. Under the section Sharing and Discovery, enable Network Discovery, file sharing, public folder sharing and others if you want to. (The screen short below gives you idea). Here first network shows connection to internet and second one the local connection with another computer.



 
Step 2: If your LAN card that is connecting to another computer is installed, it will be shown at Control Panel > Network Connections.

Step 3: Right click the Local Area Connection and click Properties.

Step 4: Under the tab ‘Networking’, click the properties internet protocol version 4(TCP/IPv4).

Step 5: Click the radio button to ‘use the following IP’ and give an IP address (Forexample: IP address: 192.168.0.1 and Subnet Mask: 255.255.255.0). Do not give any other information, Click OK and close.
 
Step 6: In Computer B, make sure you enable the LAN card which is used to connect to computer A. Here you need not give any IP information as Computer A will assign an IP address dynamically. If it is not working, make sure there are no IP assigned and change the properties to ‘obtain an IP address automatically’.
 
Step 7: Test the connection by pinging (You can do this by typing ping 192.168.0.1 or whichever is Computer ‘A’s IP in the command prompt).

Now let us share the internet connection of Computer A with Computer B

Right click the LAN card which is connected to the internet under Control Panel > Network Connections and click the Sharing tab and click both options to connect internet (Remember: Unless there is another enabled LAN setting you will not be able to see the shared tab under properties). Click OK and close. This option is given by Windows known as ICS (Internet Connection Sharing).

That is it, now you can use internet in both computers A and B.
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Connect Two Laptops Using WiFi

Sharan R >> , ,
This is step by step tutorial on how you can connect two laptops using WiFi (or two desktop computers with WiFi devices). This type of network is known as peer to peer network and is useful for file sharing and using same internet connection on both systems. So as told earlier you should have two laptops with WiFi or desktops with WiFi devices to make this connection.

Connecting Two Computers Using WiFi

Let’s name both laptops as PC1 and PC2. Now we need to set names and workgroups of both computers (Remember both computers will have same workgroups). To set the name and workgroup of both computers right click on My Computer and select Properties.

Click the tab which says Computer Name and change names of computers as you like (Here we will set computer names PC1 and PC2) and also change the Workgroup option as you like (but this Workgroup should be same for both computers).



Now you need to make “Wireless Network Connection” in PC1.
Right click on Wireless Network icon for this and click on option “View Available Wireless Network”.


Now click on option “Change Advance Settings”.


Now a windows “Wireless Internet Connection Properties” will open.

Click on the tab which says “Wireless Network” and then click Add button. Now write a name in Network Name field. You can also set a password here if you like and also remember to check the option “This is computer to computer network”.

Now press OK and “wireless network properties” will be closed.



Now in next step, you need to provide IP for network in “Internet Protocol (TCP/IP)”. For this, right click on “Wireless Internet Connection” and go in Properties and click Internet Protocols and then click Properties.
Here For example.

PC1 = IP Address: 192.168.1.1 Subnet Mask: 255.255.255.0
PC2 = IP Address: 192.168.1.2 Subnet Mask: 255.255.255.0
And Default Gateway as 192.168.1.1 (same as IP address of PC1). Having done this all, you can connect both computers using WiFi.


PC2

File Sharing Between Both Computers

Now for file sharing Enable the Sharing of “Shared Folder” in both computers. So to go in other computer, write IP address of that computer in address bar of first computer and press Enter (in this case write \\192.168.1.1 and press Enter). This will open other computer’s sharing folder where you can share file, delete files or rename them (make sure to allow these actions from other computer).

Wireless Internet Sharing Between Both Computers

It is very easy to do when you have followed above procedure. Right click on “Internet Connections” on one computer (which has internet connection in it) and go in Properties and click on Sharing and check the option which says “Allow other network users to connect through this computer” and select “Wireless Internet Connection” in “Home Network Connection”. If you want you can also check “Establish Dialup Connection” and “Allow Other Network” .



That is it. You have connected both computers using WiFi and now you can share files, play games and chat on this network.
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