The Impact of Virtual Private Network (vpn) on a Company's Network

 


 
 
 
 
Thesis Advisor 
 
 
 
 
Departmental Honors Advisor 
Dr. Zsolt Ugray 
 
 
 
 
Dr. Chris Fawson 
 
 
 


 
 
 
Director of Honors Program 
 Dr. Christie Fox 
 
 
 
UTAH STATE UNIVERSITY 
Logan, UT 
 
 
Spring 2010
 

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1 
Abstract
 
Virtual private networks (VPN) are used by remote clients to securely connect to 
company networks. This research discusses the performance of two different VPN 
configurations to determine their impact on a company's data communication network. 
The network configurations for this model are typical real-world networks complete with 
geographically diverse business office locations, a company headquarter, and a separate 
data warehouse location.
The effects of the two VPN configurations are then tested using the academic 
version of OPNET IT Guru network simulation software. Analysis of the data collected 
from the simulations show the different network performance that results from the use of 
alternative VPN setups. Managerial recommendations are made based on the results of 
this analysis. 

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2 
Table
 
of
 
Contents
 
Abstract ............................................................................................................................... 1
 
Virtual Private Networks .................................................................................................... 3
 
VPN Tunnels ....................................................................................................................... 6
 
Point to Point Tunneling Protocol .................................................................................. 9
 
Layer 2 Tunneling Protocol .......................................................................................... 10
 
IPSec Development ........................................................................................................... 12
 
IPSec Cryptography ...................................................................................................... 13
 
Symmetric Encryption .............................................................................................. 14
 
Asymmetric Encryption ............................................................................................ 14
 
IPSec Hashes ................................................................................................................. 15
 
IPSec Header Protocols ................................................................................................ 16
 
Encapsulating Security Payload ................................................................................ 16
 
Authentication Header .............................................................................................. 19
 
VPN Summary .................................................................................................................. 19
 
Test Model Development .................................................................................................. 20
 
Simulation Empirical Results ........................................................................................... 23
 
Conclusions ....................................................................................................................... 26
 
Works Cited ...................................................................................................................... 28
 
Biography, J. Myles Powell .............................................................................................. 29
 

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