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258 Chapter 7 • Wireless Network Architecture and Design Frequently Asked Questions The following Frequently Asked Questions, answered by the authors of this book, are designed to both measure your understanding of the concepts presented in this chapter and to assist you with real-life implementation of these concepts. To have your questions about this chapter answered by the author, browse to www.syngress.com/solutions and click on the “Ask the Author” form. Q: What does the G stand for in 1G, 2G, 2.5G, and 3G mobile wireless technolo-gies? A: It stands for generation and the use of it implies the evolutionary process that mobile wireless is going through. Q: What are the primary reasons that service providers use a Wireless Local Loop (WLL)? A: The primary reasons are speed of deployment, deployment where wireline tech-nologies are not practical, and finally, for the avoidance of the local exchange carrier’s network and assets. Q: Why is digital transmission better than analog in mobile wireless technologies? A: Digital transmissions can be reconstructed and amplified easily, thus making it a cleaner or clearer signal.Analog signals cannot be reconstructed to their original state. Q: Why does fog and rain affect optical links so much? A:The tiny water particles act as tiny prisms that fracture the light beam and mini-mize the power of the signal. Q: What is the difference between an ad-hoc network and an infrastructure net-work? A: Ad-hoc networks are ones where a group of network nodes are brought together dynamically, by an Access Point (AP), for the purpose of communicating with each other.An infrastructure network serves the same purpose but also provides connectivity to infrastructure such as printers and Internet access. www.syngress.com Wireless Network Architecture and Design • Chapter 7 259 Q: Several customers want me to give them up-front costs for designing and installing a network.When is the most appropriate time to commit to a set price for the job? A: Try to negotiate service charges based on deliverables associated with each phase of the design process. In doing so, you allow the customer to assess the cost prior to entering into the next phase of the design. Q: I’m very confused by all the different home network standards. Is there any way that I can track several of the different home networking standards from a single unbiased source? A:Yes.There are several means of tracking various home network standards and ini-tiatives. For comprehensive reports in the home network industry, I would sug-gest contacting Parks Associates at www.parksassociates.com.The Continental Automated Buildings Association (CABA) at www.caba.org is another good source for learning about home network technologies from a broad and unbi-ased perspective. Q: I am trying to create a design of a wireless campus network and I keep finding out new information, causing me to change all of my work. How can I prevent this? A: If you have done a thorough job in the planning phase you should already have identified all of the requirements for the project. Once you identify all of the requirements, you need to meet with the client and make sure that nothing was overlooked. www.syngress.com Chapter 8 Monitoring and Intrusion Detection Solutions in this chapter: Designing for Detection Defensive Monitoring Considerations Intrusion Detection Strategies Conducting Vulnerability Assessments Incident Response and Handling Conducting Site Surveys for Rogue Access Points Summary Solutions Fast Track Frequently Asked Questions 261 262 Chapter 8 • Monitoring and Intrusion Detection Introduction Network monitoring and intrusion detection have become an integral part of net-work security.The monitoring of your network becomes even more important when introducing wireless access, because you have added a new, openly available entry point into your network. Security guards patrol your building at night. Even a small business, if intent on retaining control of its assets, has some form of security system in place—as should your network. Monitoring and intrusion detection are your security patrol, and become the eyes and ears of your network, alerting you to potential vulnerabilities, and intrusion attempts. Designing secure wireless networks will rely on many of the standard security tools and techniques but will also utilize some new tools. In this chapter, you’ll learn about the planning and deployment issues that must be addressed early on in order to make monitoring and intrusion detection most effective when the system is fully operational. You’ll also learn how to take advantage of current intrusion principles, tools, and techniques in order to maximize security of your wireless network. Specialized wire-less tools such as NetStumbler and AirSnort will also be used to provide a better overall picture of your wireless security. Intrusion Prevention (IP) systems may offer an additional layer to detection. We’ll discuss the pros and cons of their use, and their relationship to conventional intrusion detection.You’ll also learn how to respond to incidents and intrusions on a wireless network, as well as conduct site surveys to identify the existence of rogue Access Points (APs). Designing for Detection In this section, we will discuss how to design a wireless network with an emphasis on monitoring, focusing on the choice of equipment, physical layout and radio interference.The decision-making involved in the design, deployment, and installa-tion of a wireless local area network (WLAN), combined with the choice of product vendor, can play a key role in later efforts to monitor the network for intrusions. Designing for detection occurs when you build a network with monitoring and intru-sion detection principles in mind from the start. For example, when a bank is built, many of the security features, such as the vault security modules, closed circuit cam-eras, and the alarm are part of the initial design. Retrofitting these into a building would be much more expensive and difficult than including them in the beginning. The same idea is true with a network. Designing your network for detection, having www.syngress.com ... - tailieumienphi.vn
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