wireless lan for a library: issues and challenges

54 International Conference on e-resources in higher education: Issues, Developments, Opportunities and Challenges

WIRELESS LAN FOR A LIBRARY: ISSUES AND CHALLENGES S. Ketheeswaren Assistant Librarian, University of Jaffna, Sri Lanka

Sr. Ashritha Librarian, St. Teresa College, Ernakulam

S. Rosilinmary Professional Trainee, Library, Bharathidasan University, Trichy, India

B. Visvanath Assistant Librarian, Oxford Engineering College, Trichy, India

ABSTRACT Wireless LAN is an unguided data communication network within a boundary of place. Wireless communications offer organizations and users with many benefits such as portability and flexibility, increased productivity, and lower installation costs. This paper covers many concerns of the Emerging Wireless Technologies, classification of Wireless LAN, Emerging Benefits of Wireless Technology in Higher Education, Critical challenges of a Wireless LAN and needed wireless LAN Securities. This paper generally discusses the problems freshly emerged from wireless LAN when replacing the wireless LAN in the place of wired LAN and discusses the alternatives to the problems as well. Keywords: Wireless LAN, Unguided media, Wireless Data Communication Introduction Wireless communications offer organizations and users with many benefits such as portability and flexibility, increased productivity, and lower installation costs. Wireless technologies cover a broad range of differing capabilities oriented toward different users and needs. Less wiring means greater flexibility, increased efficiency, and reduced wiring costs. Ad hoc networks, such as those enabled by Bluetooth, allow data synchronization with network systems and application sharing between devices. Bluetooth functionality also eliminates cables for printer and other peripheral device connections. Handheld devices such as personal digital assistants (PDA) and cell phones allow remote users to synchronize personal databases and provide access to network services such as wireless e-mail, Web browsing, and Internet access. However, risks are inherent in any wireless technology. Some of these risks are similar to those of wired networks; some are exacerbated by wireless connectivity. Overview of Wireless Technologies Wireless Networks Wireless networks serve as the transport mechanism between devices and among devices and the traditional wired networks (enterprise networks and the Internet). Wireless networks are many and diverse but are frequently categorized into three groups based on their coverage range: Wireless Wide Area Networks (WWAN), Wireless Local Area Networks (WLAN), and Wireless Personal Area Networks (WPAN). WWAN includes wide 19th & 20th Feb. 2010, Bharathidasan University, Tiruchirappalli.

coverage area technologies such as HSDPA 2G, 3G or 3.5 G cellular, Cellular Digital Packet Data (CDPD), and Global System for Mobile Communications (GSM), and Mobitex. WLAN, representing wireless local area networks, includes 802.11 standards like wi-fi, HiperLAN, and several others. WPAN represents wireless personal area network technologies such as Bluetooth and IR. All of these technologies are “tether-less”—they receive and transmit information using electromagnetic (EM) waves. Emerging Wireless Technologies A lot of technologies have emerged in wireless networks. While wireless networking was a luxury a few years ago, it has turned into a necessity today. Some new features of 2008 include Wireless USB and Bluetooth. The USB standard is also getting a wireless makeover, giving us, predictably enough, Wireless USB (WUSB). It is based on the Ultra WideBand (UWB) platform, a short-range, high data-rate radio frequency transmission standard. Wireless USB is designed to give 110Mbps at distances up to 10 meters. Bluetooth 3.0 is currently also under development, being built on the UWB protocol. However, unlike WUSB, Bluetooth can use security to pair devices, which when coupled with the proposed 480Mbps transmission rate, could make it a serious contender for short-range peripheral connectivity. WirelessHD (WiHD) and Wireless HDMI (WHDI) are new technologies for transmitting High-Definition videos and audio signals from one device to another.

55 International Conference on e-resources in higher education: Issues, Developments, Opportunities and Challenges

Wireless Devices A wide range of devices use wireless technologies, with handheld devices being the most prevalent form today. Most commonly used wireless handheld devices are mobile phones, laptops, PDAs, and smart phones. Classification of Wireless LAN Wireless LANs can be broadly classified into two categories: ad hoc wireless LANs and wireless LANs with infrastructure. In ad hoc networks, several wireless nodes join together to establish a peer-to-peer communication as shown in Figure 1. They typically require no administration. Networked nodes share their resources without a central server. In wireless LANs with infrastructure, there is a high-speed wired or wireless backbone. Wireless nodes access the wired backbone through access points (see Figure 2). These access points allow the wireless nodes to share the available network resources efficiently.

Fig. 1. Ad hoc wireless LAN

Fig.2. wireless LANs with infrastructure

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Benefits of Wireless Technology in Higher Education On college campuses worldwide, all stakeholders are well served by the deployment of an integrated wired and wireless network. Students and Faculty Flexibility With anytime, anywhere access to resources, students can conduct schoolwork in indoor and outdoor places and many other places around the campus. Similarly, wireless enables instructors to deliver lessons outside the classroom, such as lab exercises in field classes. E-learning Instructors can complement classroom instruction with online activities to create an integrated learning experience. Communication By providing easy access to communications tools such as e-mail and on-line group discussion boards, wireless facilitates team building across multiple disciplines. Institution: Universities and Colleges Revenue A wireless network presents potential revenue-generating opportunities. For example, universities could charge visitors for wireless Internet access. Also, colleges that may have once charged for long-distance phone services, but have seen such opportunities evaporate in recent years, might consider introducing wireless VoIP services to students. Competitiveness Today’s students are more technologically savvy than ever. Wireless access throughout campus and student living areas helps academic institutions compete for students and faculty. Innovation By fostering a more collaborative and creative learning environment, wireless technologies enables the university to better support its academic mission and research objectives. Scalability With the increasing awareness of consumer Wi-Fi products, students and faculty expect ubiquitous Internet access on campus. A wireless network enables the IT staff to quickly meet these demands across a large geographic area. Flexibility Wireless can provide network access to locations where wiring is impossible (for example, older buildings with historic value or asbestos concerns) or where access is only needed for temporary use, such as events facilities. Lower cost Cabling for Ethernet can be a costly and time-consuming exercise. In comparison, wireless can be installed much more quickly and at a fraction

56 International Conference on e-resources in higher education: Issues, Developments, Opportunities and Challenges

of the cost. Moreover, when a significant part of the campus network is wireless, operational overhead associated with adds, moves, and changes are much lower. Security Issues Emerging Security Standards and Technologies Security is a big concern in wireless networking, especially in m-commerce and ecommerce applications. Mobility of users increases the security concerns in a wireless network. Current wireless networks employ authentication and data encryption techniques on the air interface to provide security to its users. The IEEE 801.11 standard describes wired equivalent privacy (WEP) that defines a method to authenticate users and encrypt data between the PC card and the wireless LAN access point. In large enterprises, an IP network level security solution could ensure that the corporate network and proprietary data are safe. Virtual private network (VPN) is an option to make access to fixed access networks reliable. Since hackers are getting smarter, it is imperative that wireless security features must be updated constantly. Bandwidth hijacking -- Either unintentionally or maliciously, anyone with a wireless laptop or other WiFi device can tap into your bandwidth without so much as sending you a thank-you note for the free Internet access. Even more disturbing is that such a hijacker could gain access to your internal network resources through an unsecured WAP. Data encryption -- At present, there aren't many viable options for wireless encryption. The Wired Equivalent Privacy (WEP) protocol, previously the standard for wireless encryption, has been "broken" and is only really useful as a means of thwarting casual eavesdropping on a wireless connection, not to prevent the actions of a determined attacker. Critical Challenges for Wireless LAN Since wireless devices need to be small and wireless networks are bandwidth-limited, some of the key challenges in wireless networks are: • data rate enhancements • minimizing size and cost • low power networking • improving performance • user security

19th & 20th Feb. 2010, Bharathidasan University, Tiruchirappalli.

Enhancing Data Rate. Improving the current data rates to support future high speed applications is essential, especially, if multimedia service are to be provided. Data rate is a function of various factors such as the

Fig. 2: Wireless LAN with infrastructure. data compression algorithm, interference mitigation through error-resilient coding, power control, and the data transfer protocol. Therefore, it is imperative that manufacturers implement a well thought out design that considers these factors in order to achieve higher data rates. Data compression plays a major role when a multimedia application such as video conferencing is to be supported by a wireless network. Currently, compression standards such as MPEG-4 produce compression ratios of the order of 75 to 100. Low Power Design. The size and battery power limitation of wireless mobile devices place a limit on the range and throughput that can be supported by a wireless LAN. Restricted access in the wired portion of a LAN also affects the throughput. The complexity and hence the power consumption of wireless devices vary significantly depending on the kind of spread spectrum technology being used to implement the wireless LAN. Normally, direct sequence spread spectrum (DSSS) based implementations require large and power-hungry hardware compared to frequency hopped spread spectrum (FHSS). They tend to consume about two to three times the power of an equivalent FHSS system. But, the complex circuitry provides better error recovery capability to DSSS systems compared to FHSS. FHSS is generally less

57 International Conference on e-resources in higher education: Issues, Developments, Opportunities and Challenges

tolerant to multipath and other interference. In fact, there is a constant debate going on both in academia and the wireless industry regarding the pros and cons of DSSS versus FHSS. It is the right time for researchers and developers to approach these issues in wireless LAN technologies together and from a global perspective. This may also enable different vendors to develop wireless. Improving Performance If Windows ever notifies you about a weak signal, it probably means our connection is not as fast or as reliable as it could be. Worse, we might lose our connection entirely in some parts of our home. If we need to improve the signal for our wireless network, we can try some of these tips for extending our wireless range and improving our wireless network performance.

Position your wireless router (or wireless access point) in a central location When possible, place your wireless router in a central location in your home. If your wireless router is against an outside wall of your home, the signal will be weak on the other side of your home. Do not worry if you can not move your wireless router, because there are many other ways to improve your connection.

Move the router off the floor and away from walls and metal objects (such as metal file cabinets) Metal, walls, and floors will interfere with your router's wireless signals. The closer your router is to these obstructions, the more severe the interference, and the weaker your connection will be. Replace your router's antenna The antennas supplied with your router are designed to be omni-directional, meaning they broadcast in

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all directions around the router. If your router is near an outside wall, half of the wireless signals will be sent outside your home, and much of your router's power will be wasted. Most routers don't allow you to increase the power output, but you can make better use of the power. Upgrade to a hi-gain antenna that focuses the wireless signals only one direction. You can aim the signal in the direction you need it most.

Replace your computer's wireless network adapter Wireless network signals must be sent both to and from your computer. Sometimes, your router can broadcast strongly enough to reach your computer, but your computer may not send signals back to your router. To improve this, replace your laptop's PC card-based wireless network adapter with a USB network adapter that uses an external antenna. Laptops with built-in wireless typically have excellent antennas and do not need to have their network adapters upgraded.

Add a wireless repeater Wireless repeaters extend your wireless network range without requiring you to add any wiring. Just place the wireless repeater halfway between your wireless access point and your computer, and you'll get an instant boost to your wireless signal strength.

58 International Conference on e-resources in higher education: Issues, Developments, Opportunities and Challenges

Change your wireless channel Windows XP Visit Microsoft Update, click Custom, and then wait while Windows XP looks for the latest updates for your computer. Install any updates relating to your wireless adapter.

Wireless routers can broadcast on several different channels, similar to the way radio stations use different channels. Just like you'll sometimes hear interference on one radio station while another is perfectly clear, sometimes one wireless channel is clearer than others. Try changing your wireless router's channel through your router's configuration page to see if your signal strength improves. You do not need to change your computer's configuration, because it'll automatically detect the new channel. Reduce wireless interference If you have cordless phones or other wireless electronics in your home, your computer might not be able to "hear" your router over the noise from the other wireless devices. To quiet the noise, avoid wireless electronics that use the 2.4GHz frequency. Instead, look for cordless phones that use the 5.8GHz or 900MHz frequencies. Update your firmware or your network adapter driver Router manufacturers regularly make free improvements to their routers. Sometimes, these improvements increase performance. To get the latest firmware updates for your router, visit your router manufacturer's Web site. Similarly, network adapter vendors occasionally update the software that Windows uses to communicate with your network adapter, known as the driver. These updates typically improve performance and reliability. To get the driver updates, do the following: Windows Vista Click Start menu, click All Programs, and then click Windows Update. In the left pane, click Check for updates, and then wait while Windows Vista looks for the latest updates for your computer. Install any updates relating to your wireless network adapter.

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Pick equipment from a single vendor While a router of one vendor will work with a network adapter of another vendor, you often get better performance if you pick a router and network adapter from the same vendor. Some vendors offer a performance boost of up to twice the performance when you choose their hardware. Upgrade 802.11b devices to 802.11g 802.11b is the most common type of wireless network all the time, but 802.11g is about five times faster than 802.11b. 802.11g is not compatible with 802.11b, so you want to still use any 802.11b equipment in the equipments of 802.11b standard. If you're using 802.11b and you're unhappy with the performance, consider replacing your router and network adapters with 802.11g-compatible equipment. If you're buying new equipment, definitely choose with 802.11g. Wireless networks never reach the theoretical bandwidth limits. 802.11b networks typically get 25Mbps. 802.11g is usually in the 13-23Mbps range. Conclusion Even wireless LAN is changing entire network environments with new style, Wireless LAN technologies still have a long way to go in several aspects. Both fundamental and practical problems still persist in this area. Therefore, much precaution must be taken to ensure the success of emerging wireless applications when implementing high securable wireless networks. While the wireless LAN provides portability and flexibility, increased productivity, and lower installation with much easy and convenience, security is coming to play major role that we have to pay much attention on security oriented risks. Continuous LAN security monitoring is crucial. We must also much attention on Bandwidth hijacking and Data encryption by automated check and report. While the benefits of wireless LAN reflects on much of data sharing users, we have to keen in setting up wireless access points appropriately and identifying marked problems and solutions of wireless signals as discussed in the paper.