1. Introduction:

Utilization of Bandwidth Efficiently is the most Challenging factor, in today’s IT Revolution. Providing security for the data transmission over wired and wireless networks is again a very important factor in order to avoid piracy, illegal and unauthorized accesses.

Here we are investigating the effect of WPA2 security technique on the IP addressing schemes with the client-server configuration on Windows 7 – Windows Server 2008 and Windows XP – Windows Server 2008 Operating systems respectively. When comparing the techniques each other, we need to enable and disable the encryption techniques used respectively, in order to study the proper impact of security techniques on the performance of the 802.11n wireless networks.

The most important factor is to provide the better security for the data transmission over wired and wireless communication with less processing time and should use the low bandwidth as much as possible without reducing the performance; and also security is the main factor which decreases the performance of the setup by increasing the processing time [8]. This also leads in decreasing the system throughput.

Providing the better security with efficient utilization of bandwidth with reduced processing time during the transmission of data, will become the most effective and supportive step for today’s growing IT World.

IPv6 replaced IPv4 as IPv4 has failed to provide enough IP addresses to all the end user systems. Recently developed operating systems by different organizations support both IPv4 and IPv6 Protocol Stacks and Infrastructures [2].

802.11n IEEE standard is the recent development by the IEEE group, in the Wireless Fidelity category [9]. This standard provides the improved bandwidth compared to previous wireless standards. 802.11n is able to provide the improved bandwidth as it utilizes multiple antennas and wireless signals technology – The MIMO technology, where the other previous version of IEEE standards were not using this technique for the Data Transmission and Reception. 802.11n standard was finalized on nov-2009 [9].

After the successful development of 802.11n, the industries started implementing the wireless devices that provides and supports the data transmission rate more than 100Mbps in the current real world, which is the much more compared to any other wireless standards previously developed. This is one of main advantages of the 802.11n.

IPv6 is replaced by IPv4, which is new and have also been upgraded in newly developed operating systems. Windows 7 is the most recent successful development by the Microsoft Windows organization which works on both IPv4 and IPv6 addressing schemes. Most of the companies have decided to move to the new operating systems like Windows 7. Some of the companies and organizations are still using Windows XP which runs on IPv4 addressing scheme [6]. Some of the companies are addicted to Windows vista even though Vista has few bad reviews and disadvantages compared to newly developed operating systems. The working of Vista and Windows 7 are almost same. Windows Server 2008 is the new and advanced version of Microsoft [6]. This has many upgraded features, technologies, better authentication and rights of admission controls and also the added active directory services as compared to the other previous versions of Server Operating Systems from the Microsoft [6].

WPA (Wireless Protected Access) and WPA2 are the security protocols used in securing the data from unauthorized accesses during Data Communication, in Wireless Computer networks[10]. This was developed by ‘Wi-Fi Alliance’. This was developed in order to overcome the disadvantages and solve the queries that were found during research on WEP technique in various organizations and institutes as well. This WPA2 technique provides better encryption than WEP, and consists of more advanced features and techniques [10].

2. Background:

In 2009, Samad Salehi Kolahi, and the co-authors et al [1] conducted a study on Impact of Security on the IPv4 and IPv6 using 802.11n Wireless LAN on Windows Vista, Windows Server 2008 and Windows XP operating systems[1]. The main contribution of their paper was to compare the performance of IPv4 and IPv6 on a client-server configuration, in wireless 802.11n networks, using the operating systems like Windows Vista, Windows Server 2008, Windows XP and Windows Server 2008. WPA2 security encryption technique was used and then they compared the outputs with the open system 802.11n networks [1]. This paper gave me the motivation to compare and verify the performances of both IP addressing schemes and the outputs on different operating systems, when the MTU is increased and to compare the time taken to transmit the data (ex: how much time does setup1 and setup2 takes to transmit the 1Gigabyte of data respectively and compare them with each other).

MTU (Maximum Transmission Unit) is a protocol which used in the higher layers. This protocol forwards the data using MTU parameters; these parameters are always associated with the communication interface like network interface card, serial and parallel ports [13]. The MTU size is fixed by the standards or protocols which are used. For a larger MTU, the packets contain data where the protocol headers and delays are remaining fixed. The efficiency of the MTU is calculated when we use bulk data throughput. The Per-Packet-Processing technique used in this protocol may limit the performance of the system. Usually when large packets are being transmitted the transmission link used appears to be slow for some amount of time [13]. This Latency may become a factor in decreasing the overall efficiency of the setup. Sometimes when transmitting the larger packets due to some communication errors which cause the data bit loss in the arrived packets at the destination, irrespective of the error is present in all of the bits or in a single bit or in some bits of the packet, whole packet has to be retransmitted, this retransmission takes much time which is again a main factor which decreases the throughput of the setup also causes increased MAC delay. The retransmission of IP packet can be done without the fragmentation technique [13]; this fragmentation includes only the IP header except all other low level headers of the OSI layers. The minimum size of reassembled packet for IPv4 is 576 and IPv6 is 1500 bytes. The MTU for a wireless 802.11 networks is 2272 bytes [13].

3. Problem Description:

The above diagram shows the client-server configuration setup, the server is connected to the 802.11n wireless access point using a CAT 5e straight through cable. The client is connected to the access point using 802.11n NIC (Network Interface Card). Here we are investigating the performance of the 802.11n in different phases.

In the phase 1,

Step1: The Server is installed with Windows Server 2008, and client is installed with windows 7 operating system. IPv4 addressing scheme is used here in this step, no encryption technique is used during the data transmission to verify the throughput of the setup without any security encryption to verify the performance, and also to investigate the performance when MTU is increased beyond the range of 128–1408 bytes.

Step2: Here in this step the Server is installed with Windows Server 2008, and client is installed with windows 7 operating system. IPv6 addressing scheme is used instead of IPv4 addressing, no encryption technique is used during the data transmission to verify how the security factors affect the throughput performance, and also the performance when MTU is increased.

Step3: Here in this step the server remains with the same operating system and client as well, the IPv4 addressing scheme is used again instead of IPv6 but the WPA2 encryption technique is enabled. Encrypted data is transmitted in order to verify the weather the security factor affect the throughput performance and also the time taken to transmit the encrypted data and this time is compared with the time taken in the steps 1 and 2 respectively fro different MTU ranges.

Step4: The Server operating system remains same with windows server 2008, and client with the Windows 7, but the IP addressing scheme is changed back to the IPv6 then the WPA2 encryption technique is used for the transmitting data, and the outputs are measured and compared with the results of the above steps.

The outputs obtained from all the above 4 steps are compared with each other to decide which Operating system configuration and IP addressing schemes going to provide the required high throughput and better performance by plotting the respective graphs to the obtained respective outputs; and also how does the encryption technique impact on the performance of the IPv4 and IPv6 in Wireless 802.11n Networks and the system output as well.

In the Phase 2,

Step1: Windows Server 2008 is installed in the server, and client is installed with windows XP. First the IPv4 addressing scheme is used, no encryption technique is used all the encryption techniques are disabled during the data transmission to investigate the time taken to transmit data and verify the Throughput as well, and also the performance of the system when MTU is increased.

Step2: The Server is installed with Windows Server 2008, and client operating system will be Windows XP. We are using IPv6 addressing scheme instead of IPv4, all the encryption techniques are disabled during the data transmission to verify whether the security factors affect the throughput performance, and also the performance when MTU (Maximum Transmission Unit) is increased beyond its maximum limit with respect to the operating system used.

Step3: Here in this step the Server operating system will be Windows server 2008, but the client operating system is installed with Windows XP, the IPv6 addressing scheme is changed back to IPv4 but here in this step the WPA2 encryption technique is enabled during transmission. Encrypted data is transmitted in order to verify the weather the encryption security factors affect the throughput performance and also the time taken to transmit the encrypted data.

Step4: The Server operating system is installed with Windows Server 2008, , and client operating system will be Windows XP, but the IP addressing scheme used here is IPv4, but the WPA2 encryption technique is enabled here and encryption is used for the data transmission, the outputs are measured and compared with the above steps respectively.

The outputs obtained in all the steps are compared individually with each other by plotting the respective graphs which helps us in knowing which Operating system Configuration performs better and gives better throughput and the performance as well. Similarly, whether the IP addressing schemes used in the respective steps going to fetch the required high throughput and provide the better performance; finally how does the encryption technique impact on the performance of the IPv4 and IPv6 in Wireless 802.11n Networks and the system output.

Finally the outputs from both phases are compared and plotted a graph TCp Throughput versus packet size (bytes) and this graph helps us to investigate the performance of the IP addressing schemes and the security encryption techniques and their impact on the throughput performances used in the respective setups.

The outputs will be verified for different packet sizes like 128, 384, 640, 896, 1152, 1408 bytes of packet sizes in each steps of their respective phases which takes a minimum of 48 different scenarios and setups in order to clearly verify the performance of the IP addressing schemes by plotting the graphs.

The client-server setup is installed by windows 7, windows server 2008 and windows XP operating systems to compare whether the operating systems affect the throughput performance of Wireless 802.11n Networks. We also compare the WPA2 encryption security techniques with the Open system to investigate how the encryption technique affects the performance of the setup.

The IEEE paper which is published in the year 2009, the paper “The Impact of security on the performance of IPv4 and IPv6 using 802.11n Wireless LAN” which gave me a motivation to come through this idea, where the author has failed to clarify what happens if the MTU values are increased beyond the 1408 bytes, and the author has failed to give us (reader) a clear idea how does the IPv4 and IPv6 TCP/IP stack works on both Windows 7and Windows XP operating systems from the Microsoft organizations. We also investigate the time taken in the encapsulation process inside the TCP/IP stack.

4. Current Status and Development:

4.1 Literature or Technology Survey and Analysis:

In 2009, S.S.Kolahi, Zhang Qu, Burjiz K.Soorty, and Navneet Chand et al [1] compared the performance of IPv4 and IPv6 addressing scheme on a client-server Wireless 802.11n networks. The author concluded that enabling the encryption technique WPA2 results in approximately 7.07% less throughput for IPv4 and 5.42% less throughput for IPv6. The highest bandwidth obtained here is 120Mbps in 802.11n achieved in XP and IPv4, which is the highest as compared to all the other setups [1].

In 2009, et al [7]; Vasaka Visoottiviseth*, Thanakorn Piroonsith*, Siwaruk Siwamogasatham, the authors made a “ Emperical Study on achievable throughputs of IEEE 802.11n devices”, here the performance of 802.11n network is compared with the 802.11g network device,[7] the performance improvements of IEEE 802.11n are measured approximately about 85% of UDP downlink Traffic, 68% of TCP Downlink traffic, 90% of TCP and 50% of UDP Uplink Traffic, the TCP results are quite balanced throughout all the trials where the UDP results are bit more variations[7].

In 2008, et al [3] S.S.Kolahi, the author’s made a detailed study on the impact of security techniques for 802.11g on Windows Server 2003, Windows Vista and Windows XP [3]. The author’s contribution was to verify the impact of security on throughput and Round Trip Time (RTT) on the respective operating systems, when the encryption techniques are activated on the Open systems, the TCP throughput reduced by 10% on WEP-64 and 14% for WEP-128 on Windows XP [3].

In 2007, et al [4] Filho investigated the bandwidth security Trade-off in Windows XP Operating System. The outputs showed that there is a drop in the throughput about 4%, 7% and 5% when the encryption techniques WEP-64, WEP-128 and WPA are used in Open Systems [4].

In 2006, B.E Zedin et al [5] published a paper based on the impact of security on the performance of the wireless 802.11n networks.th authors were successful to prove that TCP throughput is reduced about 4% on Windows XP when WEP-64 is enabled and 7.14% when 128 bit key is enable [5].

References:

[1] The impact of security on the performance of IPv4 and IPv6 using 802.11n

Wireless LAN.

Authors: Kolahi, S.S; Zhang Qu; Soorthy, B.K; Chand, N; — Publication year

2009. New Technology Mobility and Security 2009, 3rd International

conference.

Link: http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=538467

[2] Comparison of end system IPv6 Protocol stacks.

Authors: Zeadally, S; Waseem, R; Raicu, I; — Publication Year 2004, page(s):

238-242.Communications IEE Proceedings, Vol 151, Issue 3.

Link: http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=1309776

[3] The Impact of Wireless LAN Security performance of different windows

operating systems. Computers and Communnications, 2008.ISSC 2008. IEEE

Symposium

Authors: Kolahi, S.S; Narayan, S.; Nguyen, D.D.T.; Sunarto, Y.; Mani,P.;

Link: http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=4625636

[4] “Security versus Bandwidth: The support of Mechanisms WEP e WPA in

802.11g Network,”

Authors: E.J.M.A. Filho, P.N.L. Fonseca, M.J.S Leitao, and P.S.F. de Barros,

IFIP International Conference on Wireless and Optical Communications

Networks, 2007.

Link: http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=4284142

[5] Impact of Security on the performance of Wireless-Local Area Networks,

Author: Ezedin, B.; Mohammed, B.; Amal, A; Hanadi, al, S.; Huda, K.;

Meera al, M.; Innovations in Information Technology, 2006, pp 1-5.

Link: http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=4085411

[6] Windows Server 2008, Microsoft Corporation, Published June 2008.

Link: http://www.winsupersite.com/blogs/tabid/3256/entryid/74766/windows-

server-2003-vs-windows-server-2008.aspx

(Click on Windows server 2008 White paper)

[7] An Empirical Study on achievable throughputs of IEEE 802.11n devices.

Author: Visootiviseth, V.; Thanakorn; Piroonsith; Siwaruk Siwamogsatham.

Link: http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=5291578

[13] Structure of the IEEE 802.11 MAC Frames – Wireless WLAN Wi-Fi

Configuration and Optimization tips.

Link:http://www.wireless-center.net/Wireless-Internet-Technologies-and-

Applications/1925.html

Text Book and Timelines:

[8] CCNA – Fundamentals of Wireless LANs, Cisco Networking Academy

program.

[9] S.McCann.; Official IEEE 802.11 Working group project timelines – 2009.

Link: http://www.ieee802.org/11/Reports/802.11_Timelines.htm

[10] Wikipedia 802.11n,

Link: http://en.wikipedia.org/wiki/Wi-Fi_Protected_Access

Additional references:

[11] “Measurement and analysis of TCP performance in IEEE 802.11 networks.”

Author: W.Ge,; Y. Shu; L.Zhang, L.Hao; O.W. Yang – Published year 2006.

Link: http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=4055002

[12] IEEE 802.11n Development: History, Process and Technology.

Author: Perahia.E – Communication Magazine, IEEE, Vol 46, Issue 7.

Link: http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=4557042