Networking Concepts Assignment: 802.11, VPN and WMAN Technologies

This assignment solution delves into various networking concepts, beginning with a comparison and contrast of the physical layers of 802.11b and 802.11a standards, outlining their differences in frequency, speed, modulation, and other key aspects. It then explains how the 802.11i standard facilitates client authentication against an authentication server using EAP exchange. The solution also discusses the usage of a virtual private network (VPN) to establish secure communication channels over public networks, highlighting its role in encryption and data security. Furthermore, the assignment presents a case study on ZeeTech, a multinational company, recommending the HiperACCESS technology for their Wireless Metropolitan Area Network (WMAN) implementation. Finally, the assignment concludes with a discussion of the three multiple access technologies—TDMA, CDMA, and GSM—used in 2G networks, explaining their functionalities. This document provides comprehensive insights into wireless technologies, network security, and access methods.

Running head: NETWORKING CONCEPTS
Networking Concepts
Name of the Student
Name of the University
Author’s Note:

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NETWORKING CONCEPTS
Table of Contents
Question 1........................................................................................................................................2
Question 2.a.....................................................................................................................................3
Question 2.b.....................................................................................................................................4
Question 3........................................................................................................................................5
Question 4........................................................................................................................................7
References........................................................................................................................................9

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Question 1
Compare and contrast the inner workings of physical layers for 802.11b and 802.11a
standards.
Solution
The Wireless Local Area Networks or WLANs with higher speed are extremely popular
in all sectors of the world (Vinel, 2012). These sectors are the most important sectors for any
society. The main standard for the WLANs is the IEEE 802.11. The specification of this 802.11
standard is that it specifies the physical layer and the MAC or medium access control for the
WLANs. For the physical layer of the WLANs, this particular standard has four typical
standards. They are the 802.11a, 802.11b, 802.11g and 802.11n (Bayraktaroglu et al., 2013). The
comparison and contrast between 802.11a and 802.11b are as follows:
Key Aspects 802.11a 802.11b
1. Range of Frequency Up to 5 GHz Up to 2.4 GHz
2. Speed or Rate in Mbps 6, 9, 12, 18, 24, 36, 48, 54 1, 2, 5.5, 6, 9, 11, 12, 18, 22,
24, 33, 36, 48, 54
3. Modulation Binary Phase Shift Keying,
Quadrature Phase Shift
Keying, 16 Quadrature
Amplitude Modulation 64
Quadrature Amplitude
Modulation (Orthogonal
Differential Phase Shift
Keying, Differentially
Quadrature Phase Shift
Keying, CCK (Direct
Sequence Spread Spectrum,
FH and IR)

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Frequency Division
Multiplexing)
4. FEC Rate 1/2, 2/3, 3/4 NA
5. Base Rate Up to 6 Mbps Up to 1 or 2 Mbps
6. Functions Providing eight PHY modes
and transmitting data (Naraei,
Amiri & Saberi, 2014).
Serves as the interface
between physical layer and
host device and the robustness
features are Packer
Fragmentation and Cyclic
Redundancy Check or CRC.
The above table clearly defines about the comparisons and contrasts between the two
typical standards of 802.11, which are the 802.11a and 802.11b. Both of them work in the
physical layer.
Question 2.a
Explain how 802.11i allows for a client device to be authenticated against an authentication
server.
Solution
The 802.11i standard enhances the 802.11 with various innovative mechanisms of
security for ensuring the integrity and confidentiality of messages (Alasmary & Zhuang, 2012).
Some of the new mechanisms are the additions, and others are the absolute replacements of the

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procedures of 802.11. 802.11i also allows any other standard of IEEE which is the 802.1x port
authentication algorithm, for providing a specific framework to obtain a strong management of
keys and mutual authentication (De Cristofaro et al., 2013). The authentication procedure that
starts at first is normally carried out by following two distinct ways. One way is to utilize the
Pre-Shared Key or PSK and the second way is to follow the exchange of EAP via 802.1x. This
EAP exchange is called as the EAPOL. The authentication server is needed or required to be
present during the following of EAP exchange (Vinel, 2012). The procedure of EAP exchange
makes sure that client device or the client station is to be authenticated with the help of an access
point. Once the pre shared key or the authentication of 802.1x is completed, a new shred secret
key is created (Naraei, Amiri & Saberi, 2014). This is known as the PMK or pair wise master
key. Thus, the 802.11i allows for a client device to be authenticated against an authentication
server with the help of the EAP exchange.
Question 2.b
Discuss the usage of a virtual private network in establishing an encrypted secure
communications channel between two points on a public network.
Solution
A VPN or a virtual private network is nothing but an extension of a private network that
allows its users to transmit any type of data or information in public networks with utmost
security (Uskov, 2012). The applications that are run on a virtual private network get all the
advantages from the security, functionality and management of the network. This VPN works
just like the several devices of computing connected directly. This private network is normally
created with the help of an establishment of a typical point to point connection virtually by

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dedicated connections and of course by certain traffic encryption. The encryption algorithm
helps the communication to be safe and secured from any type of intrusion in a point to point
communications on a public network (Uskov, 2012). The main advantage that VPN provides to
the point to point connection on a public network is that it acts like a wide area network or
WAN.
Question 3
Report on ZeeTech Case Study
Solution
Introduction
ZeeTech is a multinational company of export and import. There are five offices with
forty employees in each office. Around four hundred daily clients or customers are attended
daily by these offices (Naraei, Amiri & Saberi, 2014). They have thought of implementing a
Wireless Metropolitan Area Network or WMAN technology in their company, which will link
all the five offices and moreover, will provide a mobile wireless access to the field workers as
they have to travel in various sites.
Discussion
ZeeTech has thought of implementing one Wireless Metropolitan Area Network in each
of its five offices. There are few technologies of WMAN (Vinel, 2012). The best technology
should be implemented in ZeeTech for their business amongst all the other technologies. There
are three types of standards for WMANS. They are the HiperMAN, HiperACCESS and IEEE
802.16.

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The HiperMAN or the High Performance Radio Metropolitan Area Network is the
technology that provides a solution for broadband wireless for any Metropolitan Area Networks
(Wang, Zhu & Gomes, 2012). HIPERMAN normally operates between the radio frequency
range of 2 GHz and 11 GHz. The main advantage of this technology is that it enables flexible
mesh network deployments.
The HiperACCESS or the High Performance Radio Access is the technology that
provides broadband access to small and medium sized enterprises. It even provides backhaul for
the mobile systems like WCDMA, GSM, CDMA2000 and GPRS (Wang, Zhu & Gomes, 2012).
This particular technology was developed for providing a broadband system with but rates that
ranges up to 100Mbit/sec approximately. However, the most widely deployed rate is about
25Mbit/sec. It is mainly developed for the higher frequency bands like the 40,5 to 43,5 GHz
band.
The IEEE 802.16 Wireless MAN technology mainly specifies the air interface for these
networks. This technology follows the connection of first mile/last mile in the WMANs
(Bayraktaroglu et al., 2013). It mainly aims at the significant utilization of bandwidth between 10
to 66 GHz and further helps to define a MAC layer, supporting the various physical layer
specifications.
The HiperACCESS technology of WMAN would be the best technology for ZeeTech.
This provides a greater speed and also mobile communication (De Cristofaro et al., 2013).
Moreover, it provides Backhaul, which means it helps in cellular tower connection, enterprise
networks and Wi-Fi connections. It is cost effective and ZeeTech can easily afford it.
Conclusion

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Therefore, from the above discussion it can be concluded that ZeeTech is a multinational
company that deals with export and import business. This particular company has five offices in
Melbourne. All the offices have about forty employees working and around four hundred
customers or clients are attended regularly in these five offices. ZeeTech has decided to
implement a Wireless Metropolitan Area Network or WMAN technology in all of their five
offices. This will help in linking up the networks of all the five offices and also will provide a
mobile wireless access for the workers who travel regularly to various sites across the city for
their jobs. ZeeTech should select HiperACCESS technology for their WMAN implementation.
Question 4
Discuss the three different multiple access technologies used with 2G: time division multiple
access (TDMA), code division multiple access (CDMA), and global system for mobile
communications (GSM).
Solution
The main three multiple access technologies that are utilized with 2G are the Time
Division Multiple Access or TDMA, Code Division Multiple Access or CDMA and the Global
System for Mobile Communications or GSM. The description is given below:
i) TDMA: The Time Division Multiple Access is a procedure of accessing the channel for
all types of networks that are shared medium. TDMA enables all the users in sharing the similar
frequency channel (Ma, Leung & Li, 2014). This sharing is done by segmenting a specific signal
into various slots of time. The transmission is done rapidly by the users. This particular
technology is utilized with 2G.

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ii) CDMA: The Code Division Multiple Access or CDMA is the procedure of accessing
the channel, similar to TDMA. However the difference between two is that CDMA is utilized by
several technologies of radio communications (Glisic & Leppänen, 2013). The data or the
information can be transmitted by several transmitters in a single channel of communication
simultaneously. For this particular reason, various users can share frequencies. This particular
technology is also utilized with 2G.
iii) GSM: The Global System for Mobile Communication or GSM is the mobile system
of telephony that works digitally (De Cristofaro et al., 2013). This particular communication
utilizes the various TDMA technologies within it. This is utilized in all over the world.

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References
Alasmary, W., & Zhuang, W. (2012). Mobility impact in IEEE 802.11 p infrastructureless
vehicular networks. Ad Hoc Networks, 10(2), 222-230.
Bayraktaroglu, E., King, C., Liu, X., Noubir, G., Rajaraman, R., & Thapa, B. (2013).
Performance of IEEE 802.11 under jamming. Mobile Networks and Applications, 18(5),
678-696.
De Cristofaro, E., Du, H., Freudiger, J., & Norcie, G. (2013). A comparative usability study of
two-factor authentication. arXiv preprint arXiv:1309.5344.
Glisic, S. G., & Leppänen, P. A. (2013). Wireless communications: TDMA versus CDMA.
Springer Science & Business Media.
Ma, L., Leung, H., & Li, D. (2014). Hybrid TDMA/CDMA MAC Protocol for Wireless Sensor
Networks. JNW, 9(10), 2665-2673.
Naraei, P., Amiri, I. S., & Saberi, I. (2014). Optimizing IEEE 802.11 i Resource and Security
Essentials: For Mobile and Stationary Devices. Syngress.
Uskov, A. V. (2012, June). Information security of IPsec-based mobile VPN: Authentication and
encryption algorithms performance. In Trust, Security and Privacy in Computing and
Communications (TrustCom), 2012 IEEE 11th International Conference on (pp. 1042-
1048). IEEE.

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Uskov, A. V. (2012, May). Information security of mobile VPN: Conceptual models and design
methodology. In Electro/Information Technology (EIT), 2012 IEEE International
Conference on (pp. 1-6). IEEE.
Vinel, A. (2012). 3GPP LTE versus IEEE 802.11 p/WAVE: Which technology is able to support
cooperative vehicular safety applications?. IEEE Wireless Communications Letters, 1(2),
125-128.
Wang, J., Zhu, H., & Gomes, N. J. (2012). Distributed antenna systems for mobile
communications in high speed trains. IEEE Journal on Selected Areas in
Communications, 30(4), 675-683.