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984 Wireless Networks Based on WiFi and Related Technologies the refrigerator, these events possibly triggering a refrigerator replenishment RFID transaction. For more information on RFID transactions and RFID tag reader designs, the reader is referred to Chalasani and Sounderpandian (2004) and Cha- lasani, Boppana, and Sounderpandian (2005). In each of the facilities (manufacturing facility, the distributor’s warehouse, the retail store, and the consumer’s home) the tag readers are intercon- nected, as shown in Figure 13. Given the current advances and adaptation trends, the Wi-Fi is likely to be the dominating and economical wireless technology for intertag reader communication. Though there are no commercial implementations, intertag reader network will alleviate communi- FDWLRQDQGSHUIRUPDQFHORDGRQWKHEDFNRI¿FH computer system. In this section, we explore two representative designs of RFID tag reader networks (or simply RFID networks) (Passmore, 2004; RFID.com, 2006). One may use wired Ethernet (wired) links or wireless links to set up RFID networks. Instead, using only wired or wireless links, mixing both technologies may be advantageous. Combining wired and wireless network technologies to in- terconnect tag readers (denoted, nodes) provides WKHEHQH¿WVRIZLUHGQHWZRUNUREXVWQHVVDQGORZ PDLQWHQDQFHFRVWVZLWKWKHÀH[LELOLW\RIZLUHOHVV network for adapting to changing needs. In this type of network, all nodes have wireless capability to communicate among themselves. In addition, some of the nodes have Ethernet connections. There are two possible scenarios. • Most of the nodes have both wireless and Ethernet connectivity, while the remaining nodes communicate via wireless links only. This scenario models the situation where most of the tag readers are stationary and interconnected by Ethernet. There are a few temporary tag readers that connect to the tag reader network via wireless links only. • Most of the nodes have wireless capability only and the other nodes have both wireless and Ethernet connectivity. This scenario models the situation where most of the tag readers have only wireless capability and a few of the nodes are interconnected by a dif- ferent technology and link type to improve connection reliability and performance. We simulated both types of networks using the Glomosim simulator. We used 81 nodes arranged in a 9 uJULGLQDVT.P¿HOGDVVKRZQLQ Figure 14. The distance between adjacent nodes was 100 meters, and wireless radio transmission Figure 13. An RFID ad hoc tag reader network; ovals represent tag readers, while squares indicate the RFID tags on items, cases or pallets Tag Reader Tag Reader Tag Reader Tag Reader Tag Reader Tag Reader 985 Wireless Networks Based on WiFi and Related Technologies UDQJHZDVP7KHWUDI¿FORDGFRQVLVWHGRI byte packets generated at constant bit rate (CBR). All nodes were stationary for the duration of the simulation (600 seconds). All wired connections were in a near neighbor mesh pattern, in which each node was connected to its adjacent nodes in the grid. The maximum link speed was 2 Mbps (million bits/second) for both wired and wireless links. Though these rates are not representative of what is currently available, the simulation results will be helpful in understanding performance degradation with wireless links in Scenario A and performance improvement with wired links LQ6FHQDULR%:HXVHGXQLIRUPWUDI¿FSDWWHUQLQ which each node sends data to all the other nodes with equal probability. We varied the offered load to the network by varying the time between consecutive packets generated by nodes. For Scenario A, we compared the performance of two networks: one with all wired connections, and another with 9 of the nodes (indicated in black in Figure 14) spaced evenly in the grid pattern with only wireless connectivity. Static routes are used since most of the nodes are wired and mobility is not a practical option. Figure 15 gives the performance impact of wireless vs. wired connections. Up to certain loads, the 9 nodes with only wireless links do as well as they would with wired connections. Beyond that, the wireless transmission interference (interference range is 2-3 times that of valid reception range) limits achievable throughput. For the data we present, loads up to 4 packets/second/node (20 Kbps/node) can be handled by the nodes with wireless links. For Scenario B, we simulated three different QHWZRUNFRQ¿JXUDWLRQVQRZLUHGOLQNVGHQRWHG 0f), wired links among 4 nodes (denoted in blue in Figure 14) that form an equidistant 2x2 grid (4f), and wired links among 9 nodes (black nodes in Figure 14) that form a 3x3 grid (9f). Though the nodes are stationary during the simulation, the primary reason for using an all-wireless or mostly ZLUHOHVVQHWZRUNLVWKHÀH[LELOLW\RIUHORFDWLQJWDJ Figure 14. Layout of RFID tag reader network. Adjacent nodes are separated by 100 m. The size of the ¿HOGLV.Pu 1 Km. Black (dark shade) nodes are the 9 wireless nodes in Scenario A and 9 nodes with wired connections among them in Scenario B. Light shade nodes are the 4 nodes with wired connections among them in the Scenario B. 986 Wireless Networks Based on WiFi and Related Technologies readers as needed; to adapt to such network topol- ogy changes, a dynamic ad hoc routing protocol PXVW EH XVHG  ,Q WKH WZR FRQ¿JXUDWLRQV ZLWK static links, 4 or 12 wired links with 2-Mb/s data rate are used. Figure 16 shows the throughputs of these three networks. While adding 4 wired links to an all wireless network provides about 20% improvement in peak throughput, 12 wired links provide as much as 67% improvement. Since most of the nodes are wireless only, the network LVYHU\ÀH[LEOH Figure 15. Impact of wireless links in an all-wired network; throughputs of nine nodes placed in a 3 u 3 grid pattern are examined Figure 16. Impact of wired links in an all-wireless network 987 Wireless Networks Based on WiFi and Related Technologies It is noteworthy that the results for Scenario B are not directly comparable to those for Scenario A since we used static routes in the latter case. For comparison purposes, we simulated the two, wired networks with no static routes and ADV as the dynamic routing protocol. While the all- wired network is not affected, the performance of 9-wireless nodes case is reduced to about 12 Kbps/node, about 140% higher than that of the 9f case in Scenario B. But this performance comes at a cost of wiring 72 nodes vs. only 9. Using WiFi technology for warehouse net- ZRUNVLVLQHYLWDEOHDQGEHQH¿FLDO5),'QHWZRUNV represent good examples of using the technology, initially considered suitable for military and emergency civil applications, to improve busi- ness productivity. VEHICULAR AD HOC NETWORKS Vehicular ad hoc networks (VANETs) are exciting and rapidly growing examples of ad hoc network- ing in practice (ACM Sigmobile, 2005; IEEE CCNC, 2005). The US FCC allocated 75 MHz of spectrum in the 5.8-GHz band for dedicated short-range communication (DSRC) in VANETs (FCC, 2003). A new wireless standard, wireless access for vehicular environments (WAVE), de- noted IEEE 802.11p and based on WiFi, is being developed. Compared to the ad hoc networks GHVFULEHGHDUOLHUWKHUHDUHVLJQL¿FDQWGLIIHUHQFHV in the use and demands placed on VANETs. Tw o t y p e s o f n e t wo r k i n g c o n c e p t s w i l l b e u s e d to network moving vehicles: (a) One-hop wireless connectivity from a vehicle to a roadside wireless access point (V2R) and (b) multihop connectiv- ity among vehicles (V2V). V2R connectivity is similar to Internet connectivity using WiFi hotspots with mobility added. V2V connectivity will use ad hoc networking concepts similar to mixed networks described earlier. Since vehicular movement is predictable, VANETs can be de- VLJQHGWRSHUIRUPUHOLDEO\DQGHI¿FLHQWO\XQGHU network overload. VA N ETs wil l be use d t o imp rove d r ive r sa fet y in addition to providing Internet connectivity to users. Consequently, VANETs will be required to support two classes of applications: safety and nonsafety applications. Emergency road condi- tions, medical facility location, and passage of HPHUJHQF\ YHKLFOHV VXFK DV DPEXODQFHV ¿UH trucks, and police cars, are examples of safety applications. Access to Internet, streaming multi- media to consumers in vehicles, road congestion advisory, and information of nearby service facili- ties, such as restaurants and stores, are examples of nonsafety applications. To accommodate both types of applications, multiple channels, with some of them dedicated for safety applications and the others for applications in the order of priority, will be used. In contrast, WiFi is designed to use one channel for connectivity; multiple radios need to be used for multichannel operation in MANETs and hotspot networks. VANETs differ from MANETs in terms of energy constraints and security. Since the radios will be powered by the batteries and engines in vehicles, there will be few energy constraints. On the other hand, security and disruption to network connectivity will be more problematic compared to MANETs. Security is more problematic since hackers with unlimited power and without the need to physical access to a network port can launch the type of attacks currently used on the Internet more easily. Also, since VANETs use wireless links, which have less BW than the wired links used for the Internet, denial-of-service at- tacks can be devastating. Also, lack of energy constraints mean radios can use high power levels for transmissions (intentionally or inadvertently), which will cause excessive radio interference and reduce V2V network performance. 9$1(7V SURYLGH VLJQL¿FDQW QHZ EXVLQHVV opportunities for high-technology companies, service providers, and local businesses. There are 988 Wireless Networks Based on WiFi and Related Technologies VLJQL¿FDQWLPSHGLPHQWVDVZHOO,QYROYHPHQWRI the automobile industry will slow down the pro- cess of developing and deploying new technologies for VANETs. A good example is the audio system offered in new automobiles. While the audio play- ers in the consumer market advanced considerably, most manufacturers continue to offer 20-year-old technology as standard equipment, and do not provide any option to connect user equipment. Owing to the intended use of VANETs, there will EHVLJQL¿FDQWUHJXODWRU\FRQVWUDLQWVE\IHGHUDO state, and local government agencies. SUMMARY Multihop wireless networks based on WiFi tech- QRORJ\RIIHUÀH[LEOHDQGLQH[SHQVLYHQHWZRUNLQJ possibilities for various purposes ranging from personal networks within consumer homes to citywide departmental networks to wide area vehicular ad hoc networks. While the business sig- QL¿FDQFHRIFLW\ZLGHDGKRFQHWZRUNVPD\QRWEH clear in developed countries, these networks will play a crucial role in reaching consumers in rural a r e a s i n d e v e l o p i n g c o u n t r i e s . R F I D n e t wo r k s i m - SURYHWKHHI¿FLHQF\DQGSURGXFWLYLW\LQWKHDUHDV of manufacturing and distribution. The biggest DQGPRVWSUR¿WDEOHDUHDIRUEXVLQHVVRSSRUWXQL- ties may very well be vehicular ad hoc networks. Though the potential of wireless networks seems limitless, the technology available today does not provide dependable network performance of reli- ability. Extensive research is being conducted on improving the network software and hardware. The future wireless standards, such as IEEE 802.11n, which uses advanced MIMO antennas and new routing and transport protocols, will facilitate designing ad hoc networks that will be suitable for consumer use. ACKNOWLEDGMENTS Rajendra Boppana’s research was partially sup- ported by NSF grants EIA-0117255 and AIA grant F30602-02-1-0001. Suresh Chalasani’s re- search was supported in part by summer research grants awarded by the University of Wisconsin system. REFERENCES ACM Sigmobile. (2005). ACM International Workshop on Vehicular Ad Hoc Networks. New York: ACM Press. Boppana, R. V. (2006). On setting up a WiFi ad hoc network testbed. Retrieved December 2006, from http://www.cs.utsa.edu/faculty/bop- pana/projects Boppana, R. V., & Konduru, S. P. (2001). An adaptive distance vector routing algorithm for mobile, ad hoc networks. In Proceedings of IEEE Infocom. IEEE. Boppana, R. V., & Zheng, Z. (2005). Designing ad hoc networks with limited infrastructure support. Presented at the IEEE Consumer Communication and Networking Conference (CCNC). IEEE. Passmore, D. (2004). RFID: Network implications, Business Communications Review. Retrieved December 2006, from http://www.bcr.com/bcr- mag/2004/11/p16.php Chalasani, S., Boppana, R. V., & Sounderpandian, J. (2005). RFID tag reader designs for retail store applications. In Proceedings of the 11 th Americas Conference on Information Systems (AMCIS). Association for Information Systems. Chalasani, S. & Sounderpandian, J. (2004). RFID for retail store information systems. In Proceedings of the 10 th Americas Conference on 989 Wireless Networks Based on WiFi and Related Technologies Information Systems (AMCIS 2004). Association for Information Systems. Desliva, S. A. (2004). 7HFKQLTXHVWRPLWLJDWHWUDI¿F RYHUORDGDQGSURWRFROLQHI¿FLHQFLH VLQPRELOHDG hoc networks. PhD dissertation, CS Department, University of Texas at San Antonio. Desilva, S. & Boppana, R. V. (2005, March). 0LWLJDWLQJPDOLFLRXVFRQWUROSDFNHWÀRRGVLQDG hoc networks. Presented at the IEEE Wireless Communications and Networking Conference. Dyer, T. D. (2002). Design and analysis of adap- tive routing and transport protocols for mobile ad hoc networks. PhD dissertation, CS Department, University of Texas at San Antonio. Fall, F. & Varadhan, K. (1997, November). NS notes and documentation. The VINT Project, UC Berkeley, LBL, USC/ISI, and Xerox PARC. Retrieved from http://www-mash.cs.berkeley. edu/ns Federal Communications Commission. (2003, December 17). Amendment of the Commission’s Rules Regarding Dedicated Short-Range Com- munication Services in the 5.850-5.925 GHz Band. FCC 03-324. Gast, M, (2005). 802.11 wireless networks: The GH¿QLWLYHJXLGH(2 nd ed.). O’Reilly Media, Inc. Hu, Y C., Perrig, A., & Johnson, D. B. (2002). Ariadne: A secure on-demand routing protocol for ad hoc networks. In Proceedings of the 8 th ACM International Conference on Mobile Computing and Networking. New York: ACM Press. IEEE CCNC. (2005). The automobile as a network interface. Presented at the Technology Application Panel, Session 3, IEEE Consumer Communica- tions and Networking Conference. IEEE CCNC. (2006). Proceedings of the IEEE Consumer Communication and Networking Conference 2004-2006. IEEE. IEEE Computer Society LAN/MAN Standards Committee. (1999). Part 11: Wireless LAN, medium access control (MAC) and physical OD\HU3+<VSHFL¿FDWLRQV (Standard ANSI/IEEE 802.11). IEEE 802.16 Working Group on Broadband Wireless Access Standards. (2004). IEEE 802.16 standard: WirelessMAN standard for broadband wireless metropolitan area networks (Standard ANSI/IEEE 802.16). Johnson, D., Maltz, D., & Hu, Y. (2003). The dynamic source routing protocol for mobile ad hoc networks. IETF MANET Working Group, Internet Draft 2003. Macker, J. P., & Scott Corson, M. (1998). Mobile ad hoc networking and the IETF. ACM Mobile Computing and Communications Review, 2(1). New York: ACM Press. Markoff, J. (2006, February 6). Venture for sharing Wi-Fi draws big-name backers. New York Times. Retrieved December 2006 from http://www.ny- times.com/2006/02/06/technology/06mesh.html Marti, S., Giuli, T., Lai, K., & Baker, M. (2000). Mitigating routing misbehavior in mobile ad hoc networks. In Proceedings of ACM/IEEE International Conference on Mobile Computing and Networking (pp. 255-265). New York: ACM Press. Perkins, C. E. (2000). Ad hoc networking. Boston: Addison Wesley. Perkins, C. E., Belding-Royer, E. M., & Das, S. R. (2003, July). Ad hoc on demand distance vector (AODV) routing (RFC 3561). IETF. RFID-101.com. (2006). Online guide to RFID technology and products. Retrieved from http:// ZZZU¿GFRP Schneier, B. (1996). Applied cryptography (2 nd ed.). New York: John Wiley & Sons. 990 Wireless Networks Based on WiFi and Related Technologies Siva Rama Murthy, C., & Manoj, B. S. (2004). Ad hoc wireless networks: Architectures and protocols. Prentice Hall. Varshney, U. (2003). The status and future of 802.11-based WLANs. IEEE Computer, 36(6), 102-105. Zeng, X., Bagrodia, R., & Gerla, M. (1998). Glomosim: A library for parallel simulation of large-scale wireless networks. In Workshop on parallel and distributed simulation (pp. 154–161). IEEE. Zhou, L., & Haas, Z. J (1999). Securing ad hoc networks. IEEE Network Magazine, 13(6). This work was previously published in E-Business Process Management: Technologies and Solutions, edited by J. Sounder- pandan and T. Sinha, pp. 155-174, copyright 2007 by IGI Publishing (an imprint of IGI Global). Section IV Utilization and Application This section introduces and discusses the ways in which information technology has been used to shape the realm of e-business and proposes new ways in which IT-related innovations can be implemented within organizations and in society as a whole. These particular selections highlight, among other topics, e-business for SME development, and factors affecting e-business adoption. Contributions included in this section provide excellent coverage of today’s environment and insight into how e-business impacts the fabric of our present-day global village. 992 Copyright © 2009, IGI Global, distributing in print or electronic forms without written permission of IGI Global is prohibited. Chapter 4.1 Small Business Collaboration Through Electronic Marketplaces Yin Leng Tan The University of Manchester, UK Linda Macaulay The University of Manchester, UK INTRODUCTION It is widely recognized that small businesses ZLWK OHVV WKDQ  HPSOR\HHV PDNH VLJQL¿FDQW contributions to the prosperity of local, regional, and national economies. They are a major source of job creation and a driving force of economic growth for developed countries like the USA (Headd, 2005; SBA, 2005), the UK (Dixon, Thompson, & McAllister, 2002; SBS, 2005), Europe (European Commission, 2003), and de- veloping countries such as China (Bo, 2005). The economic potential is further strengthened when ¿UPVFROODERUDWHZLWKHDFKRWKHUIRUH[DPSOH formation of a supply chain, strategic alliances, or sharing of information and resources (Horvath, 2001; O’Donnell, Cilmore, Cummins, & Carson, 2001; MacGregor, 2004; Todeva & Knoke, 2005). Owing to heterogeneous aspects of small busi- QHVVHVVXFKDV¿UPVL]HDQGEXVLQHVVVHFWRUD s i n g l e e - b u s i n e s s s o l u t i o n i s u n l i k el y t o b e s u i t a b le IRUDOO¿UPV'L[RQHWDO7D\ORU0XUSK\ 2004a); however, collaboration requires individual ¿UPVWRDGRSWVWDQGDUGL]HGVLPSOL¿HGVROXWLRQV based on open architectures and data design (Horvath, 2001). The purpose of this article is to propose a conceptual e-business framework and a generic e-catalogue, which enables small busi- nesses to collaborate through the creation of an e-marketplace. To assist with the task, analysis of data from 6,000 small businesses situated within a locality of Greater Manchester, England within the context of an e-business portal is incorporated within this study. 993 Small Business Collaboration Through Electronic Marketplaces BACKGROUND Small businesses are an important driving force of economic growth and job creation throughout the world. A number of studies (Horvath, 2001; O’Donnell et al., 2001; MacGregor, 2004; Todeva .QRNHVKRZWKDWZKHQ¿UPVFROODER- rate or network with each other on a venture, the SRWHQWLDOHFRQRPLFDQGEXVLQHVVEHQH¿WVFDQEH enhanced. The possible network opportunities ZLWKRWKHU¿UPVLQFOXGHEXWDUHQRWOLPLWHGWR 1. Collaboration with other businesses to pur - chase items such as fuel and raw materials, and hence leverage collective buying power in order to negotiate a better deal (Wang & Archer, 2004) 2. Collaboration with other businesses to offer complementary goods in order to increase sales or to enter new markets (Wang & Archer, 2004) 3. Collaboration with other businesses to share information, such as product information, customer demand, transaction information, and inventory information (Ovalle & Mar- quez, 2003) 4. Liaison with other complementary service businesses to jointly bid for bigger contracts and hence enabling small business to com- pete with larger counterparts (MacGregor, 2004) 5. Liaison with other similar businesses to jointly bid for a bigger contract than they DUHDEOHWRIXO¿OE\WKHPVHOYHV 6. Form collaborative buyer-supplier relation - ships Despite government initiatives and support to promote adoption of information collaboration WHFKQRORJ\,&7LQVPDOO¿UPVHDUOLHUVWXGLHV show that ICT adoption by small businesses is still very low with a number of barriers to adoption EHLQJ LGHQWL¿HG 'L[RQ HW DO  (XURSHDQ Commission, 2002; Weiss, 2002; Fillis & Wag- ner, 2004; Stockdale & Standing, 2004; Taylor & Murphy, 2004a, 2004b; MacGregor & Vrazalic, )XUWKHUVPDOO¿UPVDUHKHWHURJHQHRXVLQ nature, therefore a single e-business solution is XQOLNHO\WREHDSSOLFDEOHWRDOO¿UPVDQGWUHDWLQJ e-business as a homogeneous concept is probably a mistake (Dixon et al., 2002; Taylor & Murphy, 2004a; Fitzgerald, Papazafeiropoulou, Piris, & Serrano, 2005). In addition, supply chains with buyers and suppliers are not homogeneous (Mc- Ivor, Humphreys, & McCurry, 2003). Findings from McIvor et al. suggest that the barriers to the adoption of supply chain systems do not lie pri- marily with the technology but with the business processes itself. The effective implementation of e-business to support buyer-supplier relationships and to optimize the value chain requires that the e-business application is fully integrated into both the buyer’s and the supplier’s business ar- chitecture and technology infrastructure (McIvor et al., 2003). It is therefore crucial that collabora- tion technology infrastructure should include the following features: open and low cost connectiv- LW\ODUJHDQGÀH[LEOHGDWDVWRUDJHV\VWHPVDQG channel integration, high security, self-service functionalities based on open architectures, and data schemes (Horvath, 2001). THE E-BUSINESS FRAMEWORK Doing business is a chain of collaborative pro- FHVVHVDVLQJOH¿UPFDQEHDEX\HUIRUDEXVLQHVV but also a seller for another business, therefore interactions among buyers, suppliers and trading partners are required (Adams, Koushik, Vasudeva, & Galambos, 2003). A retail trade can utilize a one-to-many e-business solution to reach more DXGLHQFHVDQGPD[LPL]HSUR¿WVZKLOVWDWWKHVDPH time using a many-to-one e-procurement system to streamline sourcing processes with its trading partners. Firms can also employ a many-to-many e-marketplace to achieve the above. However, in HPDUNHWSODFH UHVRXUFHVRIPXOWLSOH ¿UPVFDQ . Chalasani and Sounderpandian (2004) and Cha- lasani, Boppana, and Sounderpandian (2005). In each of the facilities (manufacturing facility, the distributor’s warehouse, the retail store, and the. (MAC) and physical ODHU3+<VSHFL¿FDWLRQV (Standard ANSI/IEEE 802.11). IEEE 802.16 Working Group on Broadband Wireless Access Standards. (2004). IEEE 802.16 standard: WirelessMAN standard. examples of nonsafety applications. To accommodate both types of applications, multiple channels, with some of them dedicated for safety applications and the others for applications in the order

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