Ipspoofing is a teachnique used to hide identity of hackers

1. When you run a scenario, the Vusers on each host machine use
the host’s IP address. You can define multiple IP addresses on a
host machine to emulate a real- life situation where users sit on
different machines.
This appendix describes:
Adding IP Addresses to a Host
Using the IP Wizard
Updating the Routing Table
Enabling Multiple IP Addressing from the Controller
The multiple IP address feature is applicable to the Web and
WinSocket protocols.

2. About Multiple IP Addresses
Application servers and network devices use IP addresses to
identify clients. The application server often caches information
about clients coming from the same machine. Network routers try
to cache source and destination information to optimize
throughput. If many users have the same IP address, both the
server and the routers try to optimize. Since Vusers on the same
host machine have the same IP address, server and router
optimizations do not reflect real- life situations.
LoadRunner’s multiple IP address feature enables Vusers running
on a single machine to be identified by many IP addresses. The
server and router recognize the Vusers as coming from different
machines and as a result, the testing environment is more
realistic.

3. Adding IP Addresses to a Host
LoadRunner includes an IP Wizard program that you run on each
host machine to create multiple IP addresses. You add new IP
addresses to a machine once and use the addresses for all
scenarios.
The following procedure summarizes how to add new IP
addresses to a host:
1 Run the IP Wizard on the host machine to add a specified
number of IP addresses.
2 Re- start the host machine.
3 Update the server’s routing table with the new addresses, if
necessary.
4 Enable this feature from the Controller. Refer to see Enabling
Multiple IP Addressing from the Controller,

4. Using the IP Wizard
The IP Wizard resides on each host machine. You run this
process one time to create and save new IP addresses. The new
addresses can be a range of addresses defined by the Internet
Assignment Numbers Authority. They are for internal use only, and
cannot connect to the internet. This range of addresses are
the default used by the IP Wizard.
To add new IP addresses to a host machine:
1 Invoke the IP Wizard from the LoadRunner program group.

5. 2 If you have an existing file with IP address settings, select Load
settings from file and choose the file.
3 If you are defining new settings, select New Settings .
4 Click Next to proceed to the next step. If you have more than
one network card,choose the card to use for IP addresses and
click Next .
The optional Web server IP address step enables the IP Wizard to
check the server’s routing table to see if it requires updating after
the new IP addresses are added to the host.

6. 5 To check the server’s routing table directly after adding the
addresses, enter the server IP address. Refer to see Updating
the Routing Table.
6 Click Next to see a list of the machine’s IP address(es). Click
Add to define the range of addresses.
IP addresses include two components, a netid and hostid. The
submask determines where the netid portion of the address stops
and where the hostid begins.

7. 7 Select a class that represents the correct submask for the
machine’s IP addresses.
8 Specify the number of addresses to create. Select Verify that
new IP addresses are not already in use to instruct the IP
Wizard to check the new addresses. If some addresses are in
use, the IP Wizard will only add the addresses not in use.
9 Click OK to proceed.
After the IP Wizard creates the new addresses, the summary
dialog box lists all of the IP addresses.

8. 10 Click Finish to exit the IP Wizard. The IP Wizard Summary
dialog box is dispalyed.
11 Note the address of the .bat file and check Reboot now to
update routing tables to initialize the NT device drivers with the
new addresses.

9. 12 Click OK .
13 Edit the .bat file by inserting your IP address instead of
CLIENT. IP.
14 Update the Web Server routing table.

10. Updating the Routing Table
Now that the client machine has new IP addresses, the server
needs the addresses in its routing table, so it can recognize the
route back to the client. It the server and client share the same
netmask, IP class and network, the server’s routing table does not
require modification.
Enabling Multiple IP Addressing from the Controller
Once you define multiple IP addresses, you set an option to tell
the Controller to use this feature.
To enable multiple IP addressing from the Controller:
1 In the Controller Scenario Window, select Scenario > Enable
Multiple IP Addresses .
2 Use the General Settings of the Controller Expert Mode to
specify how the Controller should implement this feature.