Performance Analysis of IEEE 802.11 and IEEE 802.11 Ext. Mac Protocols in MANET

IJSRD - International Journal for Scientific Research & Development| Vol. 3, Issue 08, 2015 | ISSN (online): 2321-0613

Performance Analysis of IEEE 802.11 and IEEE 802.11 Ext. Mac Protocols in MANET Atul Tripathi1 Sanjay Pandey2 2 Associate Professor 1,2 Department of Computer Science & Engineering 1,2 United College of Engineering & Research, UPTU, Allahabad, India Abstract—The wireless communication is advancement in sensor network which motivates the wireless sensor networking. Network technologies are traditionally based on wireline solutions. But the introduction of the IEEE 802.11 standards have made a huge impact on the market such that laptops, PCs, printers, cellphones, and VoIP phones, in our homes, in our offices and also in public areas have incorporated the wireless LAN technology. Wireless broadband technologies nowadays provide unlimited broadband access to users which were previously offered only to connection oriented users. In this thesis IEEE 802.11, which is a set of physical layer standard for implementing wireless local area network computer communication in the 2.4,3.6,5 and 60GHz frequency band is compared with IEEE 801.11 extension by taking various parameters like throughput, packet delivery ratio and packet drop ratio etc. the simulation is done using NS2 simulator by taking 20,40 and 80 nodes for both IEEE 802.11 as well as IEEE 802.11 extension.

Key words: Wireless Communications, IEEE 802.11, IEEE 802.11 extension. MAC, Logical link layer, NS2 I. INTRODUCTION The wireless broadband technologies were developed with the aim of providing services comparable to those provided to the wireline networks. The technology is improving at very fast rate in which the wireless groups are more concentrating on the automation which may be in home as well as in the office With the advancement in the wired and wireless networks. IEEE 802.11 is a combination of MAC layer and PHY layer specifications for executing WLAN in 2.4, 3.6, 5 and 60 GHz frequency bands. They have formed and continued by the LAN and MAN Standards Committee of IEEE 802 family. The 802.11 extension contains a chain of modulation techniques. In this paper, we overview the IEEE 802.11 standard and IEEE 802.11 extension and have seen that IEEE802.11 ext. performs better than IEEE 802.11 standards in all expect.

II. INTRODUCTION OF IEEE 802.11 IEEE 802.11 is combination of The Physical layer (PHY) and medium access control (MAC) layer the specifications for executing WLAN in 2.4, 3.6, 5 and 60 GHz frequency bands. They have formed and continued by the LAN and MAN Standards Committee of IEEE 802 family. The most prevalent are those which the amendments to the original. standard network. IEEE 802.11 was the first wireless standard developed, but 802.11b was the first one which Used widely, trailed by IEEE802.11g, IEEE802.11a and IEEE802.11n..802.11b and 802.11g use the 2.4 GHz ISM band, operating in the United States under the U.S. Federal Communications Commission. Because of this choice of frequency band,802.11 band equipment’s may occasionally

suffer interference from microwave ovens, cordless telephones and Bluetooth devices .IEEE802.11 band IEEE802.11g control their interference and susceptibility by using DSSS and OFDM signal techniques.

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Fig. 1: Structure of IEEE 802.11 See 802.11 MAC is common to all 802.11 Physical Layer (PHY) Standards.

802.11 PHY is split into two parts Physical Layer Convergence Procedure (PLCP) and Physical Medium Dependent (PMD) sublayers.

A. Physical (PHY) Layer: IEEE 802.11 standard includes three types of physical layers namely:  Frequency Hopping Spread Spectrum (FHSS)  Direct Sequence Spread Spectrum (DSSS)  Infrared (IR) The frequency band of most of the IEEE 802.11 extensions of is 2.4 GHz with 14 distinct channels. The availability of these channels are different for different country. Out of these the last channel was especially designed for Japan which was the main feature incorporated in IEEE 802.11j extension. depending on the frequency band (5.15-5.825 GHz) The IEEE 802.11a extension employs a number of channels ranging from 36-161 although it works with a fixed channel center frequency of 5 GHz. There are 19 non-overlapping channels in Europe, 12 non overlapping channels in the the U.S. frequency band for the IEEE standard in and In contrast, there are only 3 out 14 non-overlapping in case of 802.11b. IEEE 802.11n uses overlapping channels with channel bandwidth 20 and 40MHz.Peer to Peer WLAN links can be established with the help of directional antennas for a few km ranges. A typical WLAN Access Point (AP) uses omnidirectional antennas with a range of 30-50m (indoors) and 100m (outdoors).This range is greatly affected by the obstacles between the AP and the Station (STA).IEEE 802.11a suffer from increased range and attenuation compared to IEEE 802.11b/g networks, because it operates on the higher frequency range of 5MHz.Use of sectored antennas instead of omnidirectional antennas increases the aggregate WLAN data rate in a given area to 2-3 times.

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Performance Analysis of IEEE 802.11 and IEEE 802.11 Ext. Mac Protocols in MANET (IJSRD/Vol. 3/Issue 08/2015/104)

Key Max Spectrum Year Standards Rate U.S. 802.11 2mbps 2.4Ghz 1997 Table 1: IEEE 802.11standards and spectrum.

B. Medium Access Control Layer The Medium Access Control sub layer is responsible for the frame formatting, and fragmentation and reassembly, channel allocation procedure, error checking, Protocol Data Unit addressing. The MAC sub layer IEEE 802.11 deals with wired and wireless communication for multiple nodes within a LAN or Metropolitan Area Network. The Distributed Coordination Function (DCF) is the fundamental access method of IEEE 802.11 MAC which is used by stations to transmit data, contend to access the channel. PCF wastes the channel bandwidth when stations responds to a poll command by transmitting a null packet. That is why PCF is not broadly used for commercial Access Points (APs). Request to Send/Clear to Send (RTS/CTS) is another optional method that can be implemented on top of the DCF to improve the performance of channel accessing by reserving the medium for a given frame. Three different frames such: management frame, control frame, and data frame are supported by IEEE 802.11 1) Medium Access Control (MAC) Layer Access Modes: a) Distributed Coordination Function (DCF)  Based on Carrier Sense Multiple Access/Collision Avoidance (CSMA/CA) b) Point Coordination Function (PCF)  Access Point polls stations for medium Access.  Restricted to Infrastructure BSSs  Not widely implemented

Fig. 2: MAC Modes C. (RTS/CTS) Request to Send/Clear to Send If any two STAs cannot communicate directly RTS/CTS mechanism is invoke by AP For each transmission, RTS message is issued by the source and The destination STA replies to this by sending a CTS message. After receiving the CTS message, the source station starts its data transmission. The medium is assumed to be in use given in the message when they receive RTS and/or CTS message. Note that using RTS/CTS in PCF reduces the network throughput.

D. Authentication & Encryption Several encryption methods have been used To avoid unauthorized access from other Stations. Security is also handled in the MAC layer.Wired Equivalent Piracy (WEP) was One of earlier encryption mechanism But the encryption method had security vulnerabilities and the Wi-fi Alliance developed another encryption technique named

Wi-Fi protection Access (WPA).The IEEE 802.11i standard an enhanced version of WPA (WPA2). IEEE 802.11i also addressed security issues associated with authentication methods like open standard and shared key authentication and incorporated IEEE 802.1X authentication method which is now used in all the later versions of IEEE 802 family standards.

1) Implementation: Implementation is carried out using Linux based Network Simulator-2. .NS2 is an open source event driven simulator Several script have been written by taking 20, 40 and 80 nodes for 802.11, 802.11 Ext. the simulation and research supports for the wired networks, wireless networks by using TCP and UDP,IP and CBR pattern of communication.

2) Needs & Benefits:  Environment is really cheap and easily accessible and tested.  Less time consuming..  Controlled experimental conditions.

3) Different Parameters Used:  Throughput.  Packet delivery ratio.  Average delay.

III. SIMULATION RESULTS A. Throughput Result:

Fig. 3: Throughput Result 1) Packet Delivery Ratio:

Fig. 4: Packet delivery ratio:

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Performance Analysis of IEEE 802.11 and IEEE 802.11 Ext. Mac Protocols in MANET (IJSRD/Vol. 3/Issue 08/2015/104)

2) Average Delay:

result and evaluate different parameter like packet drop ratio, packet delivery ratio, throughput and found that IEEE 802.11 ext. performs better than IEEE 802.11 standard .Our future work includes the study of various IEEE 802.11 extension on other parameters of 802.11a, 802.11b, 802.11n.

ACKNOWLEDGEMENT I am grateful to Asst. Professor Mr. Sanjay Pandey sir, United College of Engineering & Research, Department of Computer science and Engineering, GBTU Lucknow for his support and help and for giving me the opportunity to carry out the thesis work by providing me with the necessary resources and materials.

REFERENCES

Fig. 5: Average delay: B. Performance Comparison of 20 nodes: Parameter IEEE 802.11 IEEE 802.11 ext.

168×103 58×103 throughput 67 23 Packet delivery ratio 13.70×10-3 6.20×10-3 Average delay Table 3: Performance comparison of 20 nodes: C. Performance comparison of 60 nodes: Parameter IEEE 802.11 IEEE 802.11 ext.

142.0×103 96.0×103 throughput 57 38 Packet delivery ratio -3 -3 13.6×10 6.2×10 Average delay Table 4: Performance comparison of 60 nodes: D. Performance comparison of 80 nodes: Parameter IEEE 802.11 IEEE 802.11 ext.

132×103 168×103 throughput 15.5 7.8 Packet delivery ratio 15.5×10-3 7.8×10-3 Average delay Table 5: Performance comparison of 80 nodes: IV. CONCLUSION There are many wired and wireless sensors network applications which has covered a wide range for industrial and home markets in which IEEE 802.11 ext. is the most famous technologies for applications requires low power consumption and less complexity and longer battery life which are better than the other wireless standards. 802.11, 802.11ext. standards are evaluated over the 20, 40 nodes and 80 nodes through various parameters like Packet delivery ratio, ,throughput and packet drop ratio From the simulations we have found that performance of IEEE 802.11 ext. with respect to the packet delivery ratio and throughput for the nodes above 50 is better than IEEE 802.11 standards while the performance of IEEE 802.11 is better for the nodes less than 60 for the same parameter and packet delay of IEEE 802.11ext. is also less than IEEE 802.11 standards.

[1] Eldad Perahia, “Intel Corporation IEEE 802.11n Development: History, Process, and Technology”, IEEE Communications Magazine, July 2008.

[2] S. Haani Masood, “Performance comparison of IEEE 802.11g and IEEE 802.11n in the presence of interference from 802.15.4 networks”, Department of Electrical Engineering, McGill University.

[3] CHEN, P.Stephen, “IEEE 802.11N mac frame aggregation mechanisms for next generational high throughput WLAN’s”, IEEE Wireless Communications, February 2008.

[4] Marina Petrova, Lili Wu, Petri Mahonen and Janne Riihijarvi, “Interference Measurements on Performance Degradation between Colocated IEEE 802.11g/n and IEEE 802.15.4 Networks”, RWTH Aachen University Kackertstrasse, Germany. IEEE 802.11-1999, IEEE Standard for Local and Metropolitan Area Networks Specific Requirements – Part 11: Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) Specifications, June 12, 1999.

[5] IEEE 802.11b-1999, IEEE Standard for Local and Metropolitan Area Networks Specific Requirements – Part 11: Wireless LA Leopoldo Angrisani, Matteo Bertocco, Daniele Fortin, and Alessandro Sona, “Experimental Study of Coexistence Issues Between IEEE 802.11b and IEEE 802.15.4 Wireless Networks”, IEEE transaction on instrumentation and measurement, VOL. 57, NO. 8, august 2008 [6] Jianliang Zheng and Myung J. Lee “A Comprehensive Performance Study of IEEE802.15.4” [7] Chih-Yu Wang, Hung-YuWei, “IEEE 802.11n MAC Enhancement and Performance Evaluation”, Springer Science + Business Media, LLC 2008.

[8] Sofie Pollin, Ian Tan, Bill Hodge, Carl Chun, “Harmful Coexistence Between 802.15.4 [9] 802.11 Wireless Networks: The Definitive Guide, M.Gast, O’Reilly, 2002

V. FUTURE WORK We analyzed the performance of IEEE 802.11 and 802.11ext in this thesis and we have seen in the simulation

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