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Hong Kong The Special Administrative Region â€Myassignmenthelp.Com

Question: Discuss About The Hong Kong The Special Administrative Region? Answer: Introducation In both the standard highlighted in this question, the physical layer highlights the working procedures of the protocols. In essence, this layer will detail the transmission and reception of data frames i.e. the 802.11 frame(tonight, 2017). The first unique item about the 802.11a standard is the use of the orthogonal frequency division multiplexing technique (OFDM) to transmit data. Now, like most other wireless networking technologies, the need to increase the available bandwidth is supported by multiple access techniques that either spread or split common communication channel among many users (signals)(Mitchell, 2017). In its operations, the 802.11a standard uses the PLCP structure (Physical layer convergence procedure) to convert transmitted frames into PLCP data units (PPDU). This unit will consist of the fields such as the MAC layer, preamble, rate and parity value. Moreover, it is attributed with the following characteristics: First, the standard through its physical layer is able to offer a 5 GHz wireless connection. This connection has high data rates of up to 54 Mbps, a critical facility for modern mobile systems that requiHong Kong The Special Administrative Regionre high data rates. Secondly, the multiplexing technique used (OFDM) splits the communication channel into 48 different segments from the original 20 MHz frequency band. Furthermore, on top of the original data rate (54 Mbps), the standard can offer varying rate of either 6, 12 or even 24 Mbps. Finally, different modulation techniques are used in conjunction with the standard depending on the data rates. Therefore, application with 6 Mbps rates will use binary phase shift keying (BPSK) and those of 54Mbps will use quadrature amplitude technique (QAM) (Geier, 802.11a Physical Layer Revealed, 2003). Similar to the IEEE 802.11a standard, the 802.11b offers a wireless alternative to wired networking, where flexibility and mobility are enhanced. This standard defines a working wireless system that supports functionalities within the short range area i.e. 300 meters. Furthermore, its operations require minimal resources which minimizes the cost and power consumption(IEEE, 2007). Now, its physical layer and other related components diversify the structure of the original standard IEEE 802.11, an outcome that increases the functionalities. In all, the following attributes are exhibited in the workings of the physical layer: First, its operation around the world falls within the ISM frequency band category, which ranges between the frequencies of 2.4 GHz and 2.4835 GHz. In some instances, the values can change slightly to 2.471 and 2.497 GHz. Moreover, the operation band is split into 14 subsections of 22 MHz thickness. These subsections overlap during operation which maximizes the space. Furthermore, the chip rate of the electromagnetic interface is usually 11 MHZ, an outcome that supports transmission rates of 1, 2, 5.5 and 11 Mbps. Finally, it uses both spread spectrum multiplexing technique (DSSS) and complementary code keying (CCK) for its operations. DSSS is used for data rates of 1 and 2 Mbps, while CC is used for 5.5 and 11 Mbps rates(Khan, 2013). Highlights: 802.11a 802.11b Freq band: 5 GHz Freq band: 2.4 GHz Data rate: 54 Mbps Data rate: 11 Mbps Modulation techniques: BPSK and QAM Modulation techniques: DSSS and CCK Like most standards seen today, the 802.11i standard is an advancement of an original standard i.e. the 802.11. Now, this general standard (802.11) offers security to wireless systems through data encryption and authentication. In the original protocol, the basic WPA (Wi-Fi protected access) was used to restrict access to wireless LAN. However, as experienced today, this protocol has very many limitations that expose the content used. Therefore, the 802.11i was developed to address these shortcomings by employing the WPA2 protocol. This protocol refined the security standards by increasing the authentication requirements and by supporting its operations using AES encryption (Advanced Encryption Standard)(electronics, 2017). For a client trying to access a server, the standard introduced new access mechanisms including robust security network which uses a four-way handshake. This handshake is completed by a group keying system that uses the extensible authentication protocol (EAP)(eTutorials, 2017). Therefore, the following procedure is followed: The client initiates the access process by sending an EAP message (notification). Its access point also sends an EAP message to identify itself. The client responds an outcome that encrypts its operations to both authenticator and the server. The server challenges the client to prove its identity. Based on the response, the server either accepts or rejects the access request. Finally, if accepted, the access port is transformed into an authorized state (Latour, 2012). Virtual private networks (VPNs) While the internet offers a convenient medium to transfer and exchange data, its also poses many security threats most of which are related to its access. Now, VPNs are industrial responses to this limitation where secure and personalized channels are used to transfer content between two parties across the open channels of the internet(Cisco, 2000). In all, VPNs are encrypted channels that protect transmitted data by restricting those who access them. In their operations, two main methods or types are used; site to site connections and remote access. Site to site connections establishes large-scale connections based on verified encryption methods. These encryptions are implemented between two different points across the internet. Remote access, on the other hand, allows remote parties to access networks such as LANs. VPNs support their operations by using special encryption keys which can be either be publicly shared keys or private keys. These keys are then supported by a wide range of protocols including IPsec which encrypts the networking infrastructure. It is through these structures, that VPNs increases the security and convenience of wireless networks(Infosec, 2008). Application of Wireless Metropolitan Area Networks (WMANs) In this scenario, we highlight the requirement given by the case study at hand, where ZeeTech requires a convenient solution for WMAN connection. In essence, the company requires an optimal technology that will facilitate the services they offer to their clients across a wide geographical area. Furthermore, the solution adopted should meet the companys resource requirement which includes cost, data capacity, installation area and security. In this case, three technologies are considered; HiperMAN, HiperACCESS and the IEEE 802.16 standard (WiMAX) (the preferred choice)(Jain, 2006). HiperMAN Like any other WMAN technology, this standard offers a broadband connection to the supported devices based on the needs of the users. In terms of operational frequency, the technology will offer a frequency range of between 2 GHz and 11 GHz, a range that enhances the functionalities of wireless devices across low frequencies(ETSI, 2009). Furthermore, the standards offer an optimal data rate of about 56.9 Mbit/s, which is averaged at 50 Mbit/s. In addition to these features, HiperMAN also has improved point to multipoint configuration (PMP), an outcome that optimizes the air interface which subsequently facilitates the application of mesh networks. This optimization is also supported by strong security features that are implemented using strong encryption and modulation instances. Finally, its implementation cost is manageable as minimal resources are needed to expand its service quota (QoS) and operation metrics(works, 2017).. HiperACCESS The second alternative to WMAN implementation where broadband services are offered to small to medium-sized systems. HiperACCESS also offers backhaul services and resources where users can benefit from the application of mobile technologies such as GPRS and GSM. Nevertheless, for the consideration of the case study at hand, HiperACCESS offers a high data rate of about 100 Mbit/sec. This rate could easily satisfy the requirements at hand, moreover, this rate is supplemented by high-frequency band applications ranging between 40.5 GHz and 43.5 GHz(ETSI, 2009). These bands offer wider coverage area for services which can increase the users service area. Furthermore, its security features are characterized by advanced access control solutions which protect the data and resources being used. Finally, the cost is amicably low as minimal physical infrastructure are used. However, unlike HiperMAN, this technology requires additional resources to meet the needs of low-frequency networks appli cations(WMICH, 2015). WiMAX (802.16 standards) The most suitable alternative for the ZeeTech operations as it provides a wide range of solutions and resources that are unmatched by the rest. To start with, the standard will combine both the operations of first mile connections with those of the last mile system. This outcome increases the overall service area which is an outlined requirement for the case study at hand. Moreover, its functionalities are facilitated by a convenient bandwidth which has a wide frequency band of either 10 GHz or 66 GHz(Omerovic). Therefore, during its operations, ZeeTech can be able to offer extended services to its customers without the limitations of space. Furthermore, unlike the previous two that either capitalize of low or high-frequency application, the technology at hand incorporates both where low-frequency applications are facilitated by an ability work below the 11 GHz band. Now, to the data rate, 802.16 offers some of the highest rates ranging from 100 Mbit/s to 1 Gbit/s, an outcome that increases its overall operational efficiency. Furthermore, its security features go beyond those of the other technologies combining authentication standards with high-end air encryption. This technology will even offer end to end data encryption which improves data control over the IP system. Finally, the cost, which is convenient based on the services and resources needed(IEEE, 2016). 2G technologies TDMA (Time division multiple access): a wireless communication technique that maximizes the bandwidth of transmission by diversifying and spreading the radio spectrum. This functionality is facilitated by an allocation method that uses time to divide the frequency of transmission. Therefore, a single channel is converted to a multiple access system. Characteristics: Uses time to allocate transmission space. Suitable for both data and voice transmission. Data range between 64 kbps and 120 Mbps. Convenient for analog to digital transmission(point, 2017). CDMA (Code division multiple access): a similar technique to TDMA, however, unlike the time allocation scheme, CDMA uses pseudo codes to transmit signals. Moreover, it is based on the spread spectrum technique, a technique that diversifies resources among many users. Furthermore, it does not allocate space but allows all signal to use the entire radio spectrum but with the necessary identification(point, 2017). Characteristics: Pseudo-codes are used to identify signals. Facilitates the transmission of large volumes of information. Both data and voice can be transmitted. GSM (Global system for mobile communications): a wireless technology that differs slightly from the rest as it designed with digital and cellular objectives. Furthermore, its an open technology that transmits both data and voice based on a circuit switching system. Therefore, a connection must be established before transmission is done. It also splits its communication channel (200 kHz) into 8 different sections which increase its transmission quota. Characteristics: Its a circuit switch technology. Suitable for both data and voice transmission(Education, 2012). References Cisco. (2000). Introduction to VPNs. Extending the Classic WAN, Retrieved 27 September, 2017, from: https://www.cisco.com/networkers/nw00/pres/2400.pdf. electronics, R. (2017). IEEE 802.11i Wi-Fi Security: WEP WPA / WPA2. Radio electronics, Retrieved 27 September, 2017, from:" https://www.radio-electronics.com/info/wireless/wi-fi/ieee-802-11i-security-wpa2-wep.php. ETSI. (2009). Broadband Radio Access Networks (BRAN); HIPERACCESS; Packet based Convergence Layer; Part 1. ETSI TS 102 117-1, REtrieved 27 September, 2017, from: www.etsi.org/deliver/etsi_ts/102100_102199/.../01.01.../ts_10211502v010101p.pdf. eTutorials. (2017). IEEE 802.11i. Retrieved 27 September, 2017, from: https://etutorials.org/Networking/Wireless+lan+security/ChaptAnswer:ng Special Administrative Region, Retrieved 27 September, 2017, from: https://www.infosec.gov.hk/english/technical/files/vpn.pdf. Jain, R. (2006). Wireless Metropolitan Area Networks (WMANs). Washington University in Saint Louis, Retrieved 27 September, 2017, from: https://www.cse.wustl.edu/~jain/cse574-06/ftp/j_6man.pdf. Khan, R. (2013). Comparison of IEEE 802.11a, IEEE 802.11b and IEEE 802.11g. Code project, Retrieved 27 September, 2017, from: https://www.codeproject.com/Articles/13253/Comparison-of-IEEE-a-IEEE-b-and-IEEE. Mitchell, B. (2017). Wireless Standards 802.11a, 802.11b/g/n, and 802.11ac. Lifewire, Retrieved 27 September, 2017, from: https://www.lifewire.com/wireless-standards-802-11a-802-11b-g-n-and-802-11ac-816553. Omerovic, S. (n.d.). WiMax Overview. Retrieved 27 September, 2017, from: https://www.lait.fe.uni-lj.si/Seminarji/s_omerovic.pdf. tonight, S. (2017). PHYSICAL Layer - OSI Model. COMPUTER NETWORKS, Retrieved 27 September, 2017, from: https://www.studytonight.com/computer-networks/osi-model-physical-layer

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