how to cheat at securing a wireless network phần 8 pptx

Project 1: Providing Satellite Building AccessWhen designing a wireless network in an enterprise building, you must determine the placement of antennas and access points for best coverag

Project 1: Providing Satellite Building Access

When designing a wireless network in an enterprise building, you must determine the

placement of antennas and access points for best coverage In this example, the

mechanical room, elevators, and communications room are sources of frequency

inter-ference that you need to consider A single omnidirectional antenna might be capable

of covering the office area in a satellite building (over 100 feet) However, with the

interference items to consider, it would be better to place omnidirectional antennas

(and access points) in each hallway, as shown in the Figure 9.5, to get better coverage

Also, each access point can provide redundancy If one access point fails, the other

pro-vides access to all computers on the floor

The access point wireless bridges will be placed on shelves near the antennas

The Ethernet ports of the access point bridges will be connected to the LAN

switches that serve the floor.The LAN switch must be configured to permit

mul-tiple media access control (MAC) addresses on the data port

Designing & Planning…

Other Antenna and Access Point Bridge Placements

There are several methods of placing antennas to have full coverage in a floor.

Directional antennas could be placed in each of the four corners of the floor

aiming at a 45-degree angle toward the center of the building To verify antenna

placement, place an access point bridge at each location and test its range with

a laptop with a wireless card It is helpful to perform this test using a roll cart, so

you can roll around the hallways, offices, and conference rooms to verify

coverage.

Project 2: Providing Wireless

Technology to the Conference Rooms

For the conference room project, plan to install one access point wireless bridge

Users requiring wireless LAN connectivity will need to install wireless LAN

net-work interface cards into their laptop computers.The access point will be configured

as a bridge with the Ethernet port connecting to the LAN jack An antenna will be

installed in the conference room.This solution meets the requirement for access to

the LAN from the hospital conference room

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As shown in Figure 9.6, the access point is placed on a shelf on the corner of theconference room A directional antenna is also placed on the corner providing access

to the conference rooms and nearby offices.The LAN switch that serves the ence room drop must be configured to permit more that one MAC address on theLAN port.This same solution is applied to each conference room in each satellitebuilding

Satellite Buildings

Elevators

Mechanical Room

Communications Room

Conference Room

Office Office Office Office

Office Office

Office Office

AP

Project 3: Providing

Building-to-Building Connectivity

There are many different ways to provide a wireless solution for Jones Hospital’s

net-work A single wireless link could be implemented between the hospital building

and each satellite building, but this solution would not provide redundancy A full

mesh could also be implemented, but it might be an overkill solution

The solution presented here is one design approach that meets the requirements

Let’s review the design requirements for this connectivity:

■ Provide a replacement to the leased T-1s that connect the

satellite buildings to the main hospital building

■ Provide increased bandwidth to the satellite buildings

■ Provide redundancy to the satellite buildings

■ Maintain a level of security and encryption for the links

Based on the requirements, the existing lease lines will need to be replaced with

wireless links from the main hospital building to each satellite building Data

encryp-tion will be enabled to provide link security.The wireless links will provide increased

bandwidth from 1.5 Mbps to 11 Mbps.To provide redundancy, we could link every

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Ethernet Port connected to LAN Drop

Hall Office Office

Conference Room

AP

building in a loop, but this would add additional cost to the solution.The dancy goal can be accomplished by just adding wireless links between building pairs;for example, adding a wireless link between Buildings 100 and 101, Buildings 200and 201, and Buildings 300 and 301 A high-level illustration of the proposed solu-tion for Jones Hospital is shown in Figure 9.7.

redun-Describing the Detailed

Design of the Building Links

As previously described, we want to create point-to-point wireless links between

buildings Some vendors have wireless devices called outdoor routers that can provide

a solution for Jones Hospital We will create an architecture using the existingrouters in each building The access-point outdoor routers will connect via

Ethernet to the hospital router We’ll use each outdoor router to create point links to each satellite building As Figure 9.8 shows, Building 100 will usetwo wireless outdoor routers to link with the main hospital router and to Building

point-to-101 for redundancy Data will be encrypted using 64-bit Wired Equivalent Privacy(WEP) or 128-bit RC4

Main Hospital Building

Building 301 Building 201

Building 200 Building 100

Building 300

Building 101

Wireless Link

This solution provides for 11 Mbps of bandwidth between the buildings and the

main hospital building, a significant increase from the 1.5 Mbps of bandwidth

pro-vided by the leased T-1 lines Also, the hospital IS team will reduce costs by

elimi-nating the monthly recurring costs for the leased lines

Let’s now look at how to add redundant links to provide backup connectivity in

case of link or device failure As shown in Figure 9.9, the main hospital router

con-nects via Ethernet to the access-point outdoor routers Each satellite building has two

access-point outdoor routers to connect to the hospital and to the other building If

the link between Building 100 and the main hospital fails, the Building 100 router

will still have access to the hospital via its link to Building 101.The same loop would

be created for linking Buildings 200 and 201 to the main hospital route and for

Buildings 300 and 301

These designs will provide redundant connectivity for all satellite buildings If

there is a problem with any link or access point device, all traffic takes the redundant

path to the main hospital router.These designs provide increased bandwidth to 11

Mbps Also, users with wireless cards in their laptops will be able to meet in the

con-ference room and access the local area network Since the leased T-1 lines are not

required, recurring costs also are eliminated

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Main Hospital Router

Part of planning and design will be to reserve network closet and computerroom space for the placement of the access point devices.We will need to estimatethe distance of the antenna cables Also, we need to determine the necessary equip-ment and obtain the building owner’s permission to place the antennas on thebuilding roof.

Implementing and

Testing the Wireless Solution

When the design phase is complete and all the equipment has been acquired, we canbegin the implementation phase.The following sections describe the steps to followwhen installing, configuring, and testing the wireless devices

Project 1: Implementing the

Satellite Building LAN Access

Install the access point devices and antennas in the building floors as described in thedesign:

Main Hospital Router

Building 101 Router

Building 100 Router

11 Mbps Link

11 Mbps Link

11 Mbps Link

Access Point Outdoor Routers Access Point

Outdoor Routers

Directional Antenna Ethernet

1 Mount the antennas in the hallways, and connect cables to the access point

devices in the nearby offices

2 Connect the access points to the floor LAN switch

3 Configure the access point frequencies, keeping configuration information

available for laptop configuration

4 Configure the access point for bridging, and enable multiple MAC

addresses on the LAN switch

At this point we are ready to test wireless access throughout the floor plan.We

begin by verifying access from each office and the conference room.The hospital

laptops can be equipped with the wireless PC Memory Card International

Association (PCMCIA) cards and configured to connect to the LAN via the access

points

Project 2: Implementing the

Hospital Conference Room

Implementation for the hospital conference room includes the same steps used in

Project 1 For the conference rooms, install the access point and antenna at the

corner of the room as described in the design diagram Place the directional antenna

so that the antenna energy covers the conference room completely.The access point

is configured for bridging (no routing) Connect the Ethernet port of the access

point to a LAN drop Configure the building switch that serves the used LAN drop

to permit multiple MAC addresses on that port.The following steps provide a

review of this implementation:

1 Mount the access point and directional antenna in the

conference room

2 Connect the access points to the floor LAN switch

3 Configure the access point frequencies, keeping configuration information

available for laptop configuration

4 Configure the access point for bridging, and enable multiple MAC

addresses on the LAN switch

Use a laptop to verify access to the LAN in the conference room and nearby

offices Make sure that the connection is reliable

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Project 3: Implementing the

Building-to-Building Connectivity

The implementation of the wireless links between buildings is made in parallel tothe current T-1 connectivity No serial interfaces are used on the existing routers Inthe server room of the main hospital, you connect the main router to six access-point outdoor routers.These routers reside in the server room, not outside Installthe directional antennas on the roof of the hospital, each pointing toward the direc-tion of its respective satellite building Install and configure the primary links

between each satellite building and the hospital before installing the redundant lines.Figure 9.10 shows, at a high-level, the primary links For implementation of the pri-mary wireless links, follow these steps:

1 Install and configure the access-point outdoor routers

2 Install the outdoor antennas and connect them to the

Main Hospital Building

Building 200 Building 100

Building 300

Building 101

Wireless Link

At this point we connect the outdoor routers to the existing building routers.

Use the following steps to make these connections:

1 Connect the routers via their Ethernet ports

2 Enable the encryption protocols for data security

3 Configure the existing routers to forward packets via the

wireless link

4 Since the wireless link provides greater bandwidth, verify that the packets

are getting forwarded via the wireless link over the leased T-1 lines

When all six wireless links are installed and are passing traffic, install and

con-figure the redundant links as shown in the steps for the primary wireless links listed

at the beginning of this section.The next task is to test and verify the links:

1 Test the routing failover of wireless links by deactivating a primary link

interface or an outdoor router

2 Verify that the building still has access to the main hospital router

3 Reenable the primary link or an outdoor router

When all of the wireless devices and links are tested, the IS Manager can place

cancellation orders for the leased T-1 links

Configuring & Implementing…

Verify the Wireless Service

When installing the wireless antennas, use the testing capabilities of the access

point devices to make sure that the wireless connection is reliable If you

encounter problems with the connection, try moving the antenna in one or the

other direction to correct the problem Verify that interference is not caused by

trees or reflection from nearby buildings.

Reviewing the Hospital’s Objectives

Hold a follow-up meeting with the IS Department and hospital teams to

demon-strate the functionality of the new wireless network and to determine the successes

or failures of the wireless project.This meeting will help you determine whether you

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need to expand the wireless access points further in the satellite buildings In themeeting held with Jones Hospital, we hear that the feedback received from the hos-pital groups is good.They are satisfied with their new ability to access the LAN fromthe satellite buildings and the conference room in the main hospital building.Themedical staff is very happy with their new mobility.

The IS manager is very pleased with the savings of leased line costs and theincreased bandwidth to the satellite buildings Since installing wireless devices ismuch faster than requesting that fiber cabling be installed, they are very pleased thatthe project was completed in a short time span

Lessons Learned

From this case study we learned how to deploy wireless technologies to extendwired Ethernet LANs for office and conference room areas.We also learned how touse wireless outdoor routers to provide campus links to an enterprise hospital network

We learned to follow the process of planning, designing, implementing, andtesting a wireless network Following this approach makes wireless projects easier tomanage.We learned to consider interference when designing for antenna placementfor best coverage of the floor area, and decided on placing two access points in thesatellite building floors because of interference in the mechanical, elevator, and com-munications rooms In addition, having two access points increases the range andredundancy of the wireless network

We decided to pair up satellite buildings to provide redundancy for the buildinglinks.This solution was not as costly as compared to creating a full mesh of wirelesslinks.We enabled encryption to provide data security to the wireless links.We alsolearned that verification testing is very important.When the wireless network isimplemented, testing access and routing will help validate the solution

In this case study chapter, we reviewed an enterprise network example involving a

hospital.Wireless local area network (LAN) devices in this scenario were to help

information services (IS) managers provide additional functionality and services By

installing wireless LAN access points, hospital personnel could access the LAN in the

conference rooms and nearby offices By installing IEEE 802.11b outdoor routers,

the hospital was able to save leased line cost and increase bandwidth to 11 Mbps

Redundancy and security issues were also addressed in this case study

We followed a wireless project approach of planning the project by gathering the

requirements and baselining the current network before designing the wireless

net-work Implementation of the network was followed by testing and verification

For Jones Hospital we gathered requirements for three projects broken out of

the main challenge of providing a wireless solution: wireless access for laptops in

satellite buildings, wireless access in the hospital building, and links between

build-ings.The requirements can be summarized as follows:

■ Provide wireless access for laptops in all satellite buildings

■ Provide wireless connectivity in conference room in the main hospital

building

■ Provide a replacement to the leased T-1 lines that connect the satellite

buildings to the main hospital building

■ Provide increased bandwidth to the satellite buildings

■ Provide redundancy to the satellite buildings

We designed a wireless access solution for the satellite buildings using two access

points with omnidirectional antennas per floor in each satellite building.The design

consisted of a wireless solution that contained an access point with a directional

antenna in the hospital conference room.We designed a wireless solution for

replacing the existing leased T-1 lines with wireless links from the hospital to the

satellite buildings Data encryption provided security for the wireless links

We outlined procedures to follow when implementing these projects.We

dis-cussed testing methods to verify that the wireless access devices and links are working

and that the range of wireless access includes all locations within the building At the

conclusion of the project, a follow-up meeting was held to gather the client’s

feed-back on the project

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Solutions Fast Track

Introducing the Enterprise Case Study

 Hospital requires wireless access for laptops in satellite buildings

 Hospital requires wireless access in conference room

 Hospital requires building-to-building wireless links

Examining Network Requirements

 The area in the satellite buildings has rooms that will cause interference tothe wireless buildings

 The area in the conference room is small

 There is clear line-of-sight from the main hospital buildings to provide awireless solution

 The distance between buildings permits wireless links

Designing a Wireless Solution

 Use two access point bridges per floor in the satellite buildings withomnidirectional antennas

 Add an access point bridge in the conference of the main

hospital building

 Use access-point outdoor routers with directional antennas for hospital tosatellite building wireless connectivity

 Add wireless links between building pairs for redundancy

 Use encryption for security

Implementing and Testing the Wireless Solution

 Install, configure, and test the access points and antennas in the satellitebuildings.Test that laptops can access the LAN from all locations in thefloor

 Install, configure, and test the access point in the hospital

conference room

 Install, configure, and test the outdoor routers and wireless links.Then

install the redundant wireless links

Lessons Learned

 Using multiple access point devices on a floor will provide additional access

range and redundancy

 Using an access point with a directional antenna in the conference room

will provide wireless access for those attending meetings

 Using encryption will provide data security for the wireless

network

 Using IEEE 802.11b outdoor routers with wireless directional antennas

provides increased bandwidth to 11 Mbps between buildings

Q:We have concerns about the security of our data—how is our data protected?

A:Wireless products come with varying levels of encryption methods to protect

data Some of the data encryption methods used are DES, 64- bit WEP, and

128-bit RC4 Also, MAC address-based access control table schemes are used

Q:What are the ranges of wireless devices outdoors?

A:Directional antennas can provide a range of up to 16 miles

Q:What routing or bridging functionality is available on access point devices?

A:Access point wireless devices can act as bridges or routers.They can be

config-ured with static routers or with simple Routing Information Protocol (RIP)

They can also be configured to filter based on a MAC address when acting as a

bridge

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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: How will wireless laptops acquire an IP address and other IP-related

information?

A:When using wireless bridges, you still use your existing Dynamic Host

Configuration Protocol (DHCP) servers on the network to acquire an IP address,subnet masks, default gateways, Domain Name System (DNS) server, and other IPinformation regularly configured via DHCP No special changes are required toaccess the DHCP server

Designing a

Wireless Industrial

Network: Retail

Case Study

Solutions in this chapter:

 Solutions Fast Track

 Frequently Asked Questions

Experts in the industrial environment acknowledge the growing need for wirelesstechnology.The emerging wireless handheld devices dramatically expand mobilitywhen applied to standard industrial activities like inventory and stock management.The increased productivity and cost savings far outweigh the cost of investing innew wireless technology.This chapter describes how to implement a wireless net-work in an industrial environment Although there are various types of industrialapplications, we will focus on applying wireless technology to a retail store environ-ment Retail stores implement wireless technology for a number of purposes,

including helping their employees to track inventory using a mobile system, andallowing customers to self-scan purchases and check the price of items

Although it may be easier to think of applying wireless technology to largesuperstores, the mobility that wireless provides offers a big advantage for smallerstores Smaller stores cannot support the number of employees or merchandise thatlarge superstores do, so if they implement wireless technology they are able tostreamline the staff dramatically By adding mobile devices, a store owner can providecustomers with the ability to answer their own questions about pricing and inven-tory Customers who are more self-reliant do not require as much help from staff.Similarly, employees with self-reliant customers do not require the same amount ofsupport from their management

Through the case study presented in this chapter, you will learn how a sulting company can apply the design principles described in previous chapters.Theflow through the discovery and planning phases show typical real-world issues andevents.The planning phase contains the details you must be aware of when imple-menting a similar type of wireless network.The implementation section of thischapter walks you through the process of integrating the existing wired networkwith the proposed wireless network

con-Applying Wireless

Technology in an Industrial Network

In the past two years, companies like 3Com Corporation have designed wireless lular digital packet data (CDPD) networks for consumer applications on popularpersonal digital assistants (PDAs) More recently, by coupling wireless 802.11b tech-nology with their IPAQ PDA, the Compaq Computer Company is successfullyimplementing wireless technology in the industrial setting.With data rates that sup-port up to 11 Mbps, companies are finding useful applications for everything fromnetwork troubleshooting for corporate LANs to inventory control directly from

these mobile devices.Transmeta’s TM3200 chipset provides more effective processing

power As this power is incorporated with the operating system efficiency of Linux

in handheld technologies, an explosion of new and enhanced applications will find

their way to these powerful devices

Although size is an issue with mobile units, companies like Symbol Technologies

are finding unique ways to shrink wireless devices to allow customers and employees

to perform simple retail functions while roaming through a store Beyond these

immediate examples, several key benefits are inherent when wireless technology is

incorporated into business processes

The retail side of this industry is rapidly warming up to wireless technology

Recently, large department chains like Sears, Roebuck and Co and Wal-Mart

imple-mented handheld devices for employees.These devices enable the employee to check

inventory quickly, make price changes, enable merchandise pickup, and maintain

adequate stock Customers benefit when companies like these use handheld devices

to prescan items prior to checkout

Introducing the Industrial Case Study

In this case study, Bob Tucker, the owner of a large retail sporting goods store called

Pro Sports, is interested in applying wireless technology to make his network more

efficient and to increase customer service His current sales figures are looking solid,

but in his market environment, competitors could soon be moving in down the

street Future competition will drive prices, but it will more clearly drive service

Bob has kept up with wireless trends in the retail market, including the wireless

checkout bays used in a few superstores in his area It appears to him that customers

are eager to use new technology

He also knows that he needs to increase employee productivity and customer

response After analyzing current growth and predicting future sales trends, Bob

believes he must either increase his full-time sales staff by three employees or

imple-ment technology that will likewise expand sales efficiency and customer response

This choice makes the incorporation of wireless technology a value proposition to

weigh against future plans One of the main reasons to implement wireless

tech-nology is to provide better customer service

Assessing the Opportunity

Bob Tucker evaluates Pro Sports’ needs and develops a list of the benefits he wants to

add for employees and customers For the employees, he seeks to automate in-store

inventory Currently, employees manually track the inventory during off-hours

322 Chapter 10 • Designing a Wireless Industrial Network: Retail Case Study

During regular hours, office personnel enter the inventory lists using the PCs in thecompany office He figures that he can save money when employees take inventoryvia handheld devices.This eliminates the reentry performed in the office, and theemployees can take the inventory during normal working hours

Bob wants his shipping clerk to place items in inventory as they are unloaded inthe docking bay He projects that the handheld devices will enable the

shipping/receiving clerk to add to the inventory real-time as merchandise comes offthe truck.This activity will eliminate the extra effort it takes to provide the paper-work to the office for manual entry.This automation will also enable other

employees to check stock accurately and quickly for items that just arrived Anotheradvantage to adding this capability to the shipping/receiving area is that wirelesstechnology will enable the shipping/receiving clerk to access the current wired net-work.The PC used in the shipping/receiving department currently is not connected

to the office PCs It is a stand-alone PC with a separate software package that is nottied to the company accounting system

Handheld devices will enable the employees to respond to customer pages.Thesedevices will make it easy to assess the customers who need assistance and respond tothem quickly.When a customer requests specific information, the sales associateswith that particular expertise can respond Since employee incentives are based oncommission and customer satisfaction, handheld devices will become sales associates’pagers.What better chance of earning a commission can Pro Sports offer to theemployee than answering a customer’s page?

Bob figures that the customers will benefit from the wireless technology byenabling them to check for stock and prices For example, as the sports seasonschange, the shoe department is often one of the busiest departments By giving cus-tomers handheld devices and allowing them to scan the bar codes of the displayshoes, the customers can check to see if the inventory contains shoes of that type intheir size Although Bob’s office team works hard to print price tags for incomingitems, human errors occur and sometimes items show up without price tags.Thehandheld device enables the customer to scan an item’s bar code for pricing if aprice tag is not available.This device will also provide a map to help the customerlocate items within the store

Handheld devices can eliminate the customer’s wait in long lines Customers canscan their items and present the device to the cashier at the register.The cashierdownloads the information from the handheld device.This step is particularly useful

on weekends and holidays when the store is very busy Bob figures that this featuremay eliminate his need to hire extra holiday seasonal help

After careful consideration, Pro Sports contacts your wireless networking firm tocreate a design to see if these goals can be met by implementing wireless technology

in the store.The results of the wireless implementation in this store might open up

additional opportunities throughout the chain.The opportunity for future sales and

support makes it clear that your planning must be thorough, your design must be

efficient, and your hardware selections must be cost-effective

Defining the Scope of the Case Study

This is the first implementation of wireless technology in the individually owned

Pro Sports chain, so the current intention for this network is limited to the single

store and does not include network access to other stores at this time However, the

results could lead to adding wireless networks to other stores within the chain.The

existing computer network is in place and running fine.There is no need to modify

the existing computer network other than to integrate the wireless system with the

existing network

Pro Sports is located in a spacious two-story building Both floors contain

mer-chandise that is organized to attract customers and lead them through the store.The

attached warehouse acts as a receiving dock for merchandise Employees use the

warehouse for inventory overflow and office activities, like general company

accounting (accounts payable, accounts receivable, and payroll) For convenience, the

company offices are located in the warehouse

The existing wired network consists of an Ethernet local area network (LAN)

that connects the registers to the computer system in the company offices.The

com-pany offices consist of several desktop computers, three network servers, an Ethernet

switch, and a router for wide area network (WAN) and Internet access.The wireless

technology that will be implemented includes handheld scanning devices and a

wireless card for an existing PC

We will not address data security in this case study No confidential data will be

transmitted using the handheld devices.The handheld devices have the capability to

swipe credit cards for payment, but Bob Tucker has stated that he does not want any

credit card transactions transmitted over the wireless network, not wanting to risk

the possible interception of personal customer data

Reviewing the Current Situation

To make sure that your team understands the situation, Bob outlines his need to add

wireless technology to Pro Sports.To recap, he needs to tie the shipping/receiving

PC into the existing network and enable instant stocking by the shipping/receiving

clerk through the use of a handheld device.The system must provide customers

more autonomy by enabling price checks, inventory checks, a virtual shopping cart,

an online store directory, and customer assistance paging.These features must be

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implemented on handheld devices.The intended benefit is to save time and money

by making the employees mobile and more responsive

Designing and

Implementing the Wireless Network

The approach is straightforward—you must determine how to address the customer’sneeds and make sure they are well defined; the owner and his management team mustverify information about the employees and the customers for you After the approach

is determined, you’ll begin the planning by defining the network elements and theirplacement, and gathering details about the physical space and the intended use

After ample design time, your team will purchase the hardware elements, andthen implement the design by installing and configuring the hardware elements andmaking the necessary software changes During implementation, you’ll have to testevery aspect of the system, including the range of the handheld devices and theability to check bar codes on the loading dock At the end of the implementationphase, you should be able to verify that the results fulfill the needs of Pro Sports

Creating the High-Level Design

Your team considers setting three subdomains to make it easier to divide the workand find where to place the access points.They will also make it easier for you to cat-egorize and track progress as you set up the network.These subdomains include thefirst floor, the warehouse, and the second floor.Two of the subdomains are dividedbecause of the physical boundaries between floors; it is easier to plan the integration

of the wireless elements and the existing network elements by floor.The functionalboundary of the warehouse naturally makes it a separate subdomain.The warehousedoes not need to address any customers; only a few employees work in or around thewarehouse

It is determined that handheld devices will be used in each of the subdomains.Employees and customers will use handheld devices in the first floor and the secondfloor Only a few of the employees will use handheld devices in the warehouse.These employees perform specialized tasks, like shipping/receiving or accounting.The team identifies the additional need for a wireless-enabled PC in the

shipping/receiving area of the warehouse

At this point, the owner wants to make an investment of 100 handheld devices

He feels that the majority of these devices should be available for the customer Hedoes not want so many that they end up hanging on the wall, but he does not wantthe customers to have to wait for the use of a handheld device As a result, Bob

chose a number that he felt would be balanced between the two situations.You will

have to determine with his help the total number of employees that will use

hand-held devices and the division of the work force per floor His responses will help in

determining where the access points will be located later on in the design

Creating a Detailed Design

Your consulting company invests some time into the planning and design of the

wire-less network for Pro Sports, addressing the following tasks:

■ Obtain a physical map to chart all aspects of the building, including

elec-trical outlets, Ethernet cabling, and existing network elements Since the

new wireless network will have to interface with the existing one, knowing

the details of the current network will help you make decisions

■ Talk to the owner about expected user density How many customers does

he expect to have on either of the floors at one time? How does he assign

employee activities? What is the maximum number of employees scheduled

to work on each floor? The answers to these questions help determine the

number of access points required for efficient transmission, as well as where

to put the access points

■ Identify any constraints that may limit the design of the wireless network

When you identify constraints early, you have more time to work around

the issues Constraints can be physical, such as no access to electrical outlets

The consumer can also mandate constraints

■ Conduct a walk-through to verify information on the physical map.This

helps you account for any deviance from the physical map to the existing

structure A deviance can occur when store improvements are not added to

existing documentation.Walk-throughs also provide you with additional

information For example, if there was no access to an electrical outlet but a

light fixture was located nearby, you could assume that an electrical

con-nection can be established close to the light fixture

■ Identify any potential radio frequency (RF) interface sources Any electrical

appliances using the 2.4GHz range can affect the reliability of the wireless

network, such as microwaves and 2.4GHz cordless phones

■ Determine the size of the store and the radius of RF transmission Apply

the facts regarding the size of the store and the expected user density to

determine the required range of RF transmission.While planning this

radius, make sure you record any overflow coverage

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■ Plan the access point locations to take advantage of transmission coverage.Make sure one or two radios are added to the access point as needed fortransmission Extend the radio antennas as needed for coverage.

■ Determine Internet Protocol (IP) addresses.You can identify network ments (wired and wireless) by IP addresses.The IP addresses must beunique within the network.The Dynamic Host Configuration Protocol(DHCP) server enables you to set the IP range and monitor use of theaddresses

ele-■ Define the process to integrate the new wireless infrastructure into theexisting computer network Certain capabilities, like IP addressing andtracking are available in the existing network.The new wireless system canrely on the same DHCP server that controls the existing IP range

All of these points must be addressed as you progress through the network opment phases of planning and design

devel-Obtaining a Physical Map

The physical map contains information about the placement of the different areas ofthe store, information about the current wired network, and other physical charac-teristics, like access to electricity.These particulars provide the physical details usedwhen combining the wireless elements to the wired elements For example, if there

is no access to electricity, a network element cannot be plugged in An additionalphysical requirement is that access points must connect to the Ethernet cable of theexisting network

The 10 old steel-framed Pro Sports building projects a spacious feeling with foot high ceilings.The 18,000 square foot retail store is composed of a 10,000 squarefoot first story, a 4000 square foot warehouse expansion at the back of the first story,and an 8000 square foot second story.The load-bearing first floor contains fourcolumns that dissect the room.The second floor does not contain any columns.Thedrop ceilings for each floor allow for four feet between the second-story floor andthe first-story ceiling, and the roof and the second-story ceiling.The drop ceilingscan provide enough room to accommodate the weight and the space requirements

20-of the access points

Figure 10.1 illustrates the layout of the departments on the first floor of ProSports.The first floor contains various clothing departments, a shoe department, abaseball/soccer department, a golf department, a seasonal department, and a sun-glasses department Generally, the most active of all the first-floor departments is theshoe department, which contains tennis shoes, cleats, boots, and specialty sports shoes

for everyone in the family—note that the merchandise planners placed the most

active department in the back of the store.The planners implemented this store

design to influence customers to buy other items as they walk through the store

The owner has placed ten checkout registers near the outside doors on the first

floor During the weekdays, up to seven of the ten are available for checkout On

weekends and during holidays, all ten checkout registers are open for business As a

rule, Bob Tucker does not like to see more than two people waiting per checkout

line.There is one register at the return counter to enable the employee to process

customer requests for exchanges and returns, and to return items to inventory One

register is available in the sunglasses department All sunglass purchases must be made

using this register; this is a physical security implementation due to the

ever-increasing prices in the sunglasses department and the portability of the merchandise

www.syngress.com

200 ft

1st Floor

Shoes

Women’s Clothes

Children's Clothes

Baseball/Soccer

Men's Clothes