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Pre-Site Survey Form Information

Most work orders or job assignments begin with a pre-site survey form being filled out by one or more individuals, including the customer, IT staff, facilities personnel, and application specialists. One benefit of using this form is that it prompts those involved in completing the form to consider all their potential WLAN needs and discover other potential networking needs. This form also gives the WLAN engineers a chance to converse with the customer to explore other potential issues, such as additional bridging requirements that were not originally considered or aging, incompatible network components. This information is then used to manage the project by scheduling an appropriate amount of time for the engineer to complete the work and providing for any special considerations such as a high-lift rental or security escorts.

In addition, these forms ask important questions that might save days or weeks of extra, unbudgeted effort once the engineer is on site. Those involved in completing this form need to understand that minimal time required to fill out this form will save money and time in the long run. For example, performing a survey at an aluminum smelting plant or oil refinery will require that all engineers take the required Occupation Safety and Health Administration (OSHA) safety courses offered by the plant. This can add several days per person to the survey process. It is better to know this prior to development of the work schedule.

The following basic sequence of events helps facilitate the flow of work at both your company and the survey at the client's site:

The survey engineer or WLAN project manager sends the pre-site survey form to the IT staff responsible for the facility where the WLAN will be installed. In addition, this form is routed to those individuals responsible for implementing the new applications on the WLAN as well as to a few key WLAN users.

Data is collected and entered on the pre-site survey form, which is then returned to the survey engineer or WLAN project manager.

The survey engineer or the project manager then sets up a series of interviews with key IT personnel, WLAN end users, and facility personnel as necessary, based on the returned pre-site survey. The interview is intended to ask the questions that may have been overlooked or that the responses on the pre-site survey form generated. Issues such as hazardous materials, explosive gases, or imaging equipment such as x-ray machines or MRIs need to be discussed.

The survey engineer or the project manager then determines the resource requirements and schedules the work to be done.

The site walkthrough occurs. If possible and within the time and budget constraints, a pre-site survey walkthrough can provide a large volume of information. This can assist in completing the pre-site survey form and prepare you much better for the actual survey.

The information that you should collect can be broken into the following parts:

Customer information

Site survey location

Current network and communications information

WLAN equipment requirements

Site information

Survey personnel requirements

Scope of work

Coverage map

Outdoor bridge link

Appendix D, "Sample Forms."

Customer Information

The first part of the pre-site survey form contains all the relative information about the customer and the site as well as administrative information such as the job or work-order number (if your company uses this method to track projects).

Work-order number This is an administrative tracking number for your own use depending on how your company assigns or tracks project engagements. Many companies use sequential numbers for every quote, site survey, and then installation performed. This work-order number might include a customer identification number, too.

Date This is your company's administrative date for the delivery of the form to the customer.

Purchase order (PO) number The person contracting the work may not be the person responsible for paying for the work. In fact, larger, more complex companies may have several departments with this responsibility. You will find it very helpful to have the customer's PO number for the purpose of tracking payments with an Accounts Payable (AP) department.

PO date Knowing the PO date can be very helpful when tracking payments with the customer's AP department.

Company name Your customer's company name might not be the name of the company you are doing the site survey for. As a consultant or contractor, you might do this work at many different companies for your customer.

Address, city, state, zip code Many larger companies have several national and international offices; this can make it difficult to track the customer responsible for contracting the site survey, so it is important to have the actual office address of that person or group of persons.

Point of contact (POC) name In most cases, you will interface with one primary person for the overall WLAN project, as well as an individual responsible for the activities that occur at any particular site. They might be one and the same, so it is best to identify that person for informational purposes.

Phone, fax These entries should have the relative business telephone and fax numbers of the contracting person.

E-mail Much of today's communication is via e-mail for reasons such as the ease of retransmitting a conveyed message to many or being able to track conversations and their progression. E-mail communication about any project can be of great benefit for a number of reasons; therefore, I highly advise using this as a means of communication over the span of any project or relationship.

Mobile phone Many people travel or work remotely in today's world of telecommuting. Because of that, it is always handy to have a person's mobile telephone number.

Site Survey Location

Many times, the site survey will not be at the location of the corporate office. Many companies today are located across multiple buildings, campuses, cities, or even countries; and when one project is started for one facility, it will be implemented company-wide. For this reason, the location where the actual work will be completed needs to be identified for each individual facility. Fill out a separate pre-site survey form for each facility or building. Much of the information might be similar, but there may be distinct differences between them as well.

Be sure to note the following:

Total number of sites Determine how many sites overall require a site survey. Also identify which site this form is dedicated to (site x of x).

Site name The site name will continuously be referred to in documentation, such as the survey report and installation reports. It is important to define what the name is in the event of multiple sites or multiple buildings in a campus environment so that the technician can go to the proper location.

Working hours After the customer determines the working hours that the surveying technician can work, the sales or project management staff can derive information such as special considerations for day or night work and the total number of work days that a project may take if the available working hours are less than a standard business day of eight or nine hours.

Point of contact (POC) information In most cases, there is one primary person who interfaces with you at the specific site. This person might not be the same person who is your overall project point of contact identified at the top of the form. This person might also be responsible for your access to a particular facility. You might find it helpful to touch base with this person prior to arriving at the work site.

Current Network and Communications Information

Chapter 9, "Discovering Wired Network Requirements," information about the existing wired network is essential to completing a site survey. Details of the type of network and the topology, as well as a location of the network components, should be included in the pre-site survey form, as follows:

fading technology, many sites still have Token Ring installed. This can lead to issues related to the lack of WLAN products available for Token Ring connectivity.

WAN connectivity Define the overall network, indicating whether and how multiple sites are connected together via any type of wide-area network.

frequency, modulation).

authentication and encryption systems. Cisco has produced several white paper documents regarding WLAN security that will help you understand this issue. One of the documents is titled "SAFE: Wireless LAN Security in Depth."

WLAN Equipment Requirements

Understanding what is expected of the WLAN is vital to a proper site survey. Although coverage area is obvious, many other WLAN parameters are needed to perform a thorough and complete site survey. Coverage, data rate, rate shifting redundancy, and packet size all affect the method used to perform a survey.

Note the following when determining WLAN equipment requirements:

Chapters 7, "Site Surveying Equipment," 10, "Using Site Surveying Tools," and 11, "Performing a WLAN Site Survey," discuss this topic in more detail.

Balancing Wants, Needs, and Capabilities" section later in this chapter.)

Chapter 5, "Selecting the WLAN Architecture and Hardware," discusses this in detail.

Packet size As packet size increases, the likelihood of interference on that packet increases. This in turn reduces the overall range of the system. Maximum packet size should be identified because this is a parameter used during the actual survey process.

Coverage areas Using the floor plan or building blueprint, identify the desired coverage areas. Note whether this is indoor or outdoor coverage as well.

Applications that will use the installed equipment If the WLAN is proposed for a specific purpose, every detail must be explored, including the applications that will require the use of a WLAN.

Special needs This section gives the customer an opportunity to specify a level of protection or insurance that must be built in to their WLAN. You know, for example, that a high-availability WLAN supporting medical applications is important to medical professionals. Now compare that need with a WLAN used to support point-of-sale transactions in a retail environment. If that network has a problem, the retail store cannot do business. In a medical environment, however, the network might provide a link for life-support monitoring.

Site Information

Each site will likely have different physical characteristics and requirements. Therefore, you might need to perform surveys differently. If the site includes indoor and outdoor areas, antennas that are capable of outdoor installations might be necessary. If the site has extremely high ceilings or very low ceilings, you need to use the appropriate antennas for the survey. Other characteristics such as temperatures, hazardous environments, and public areas can also affect what equipment is needed for the survey.

Note the following site information:

Chapter 11.

Floor construction Floor construction impacts the propagation between floors of a multiple-floor building. This issue is especially significant with regard to construction techniques today that use a metal underpanning that is installed to allow concrete to be poured on top of it. This underpanning isolates RF coverage cells to a single floor in most cases.

Ceiling height Ceiling heights in any environment impact propagation patterns and work areas. A surveying technician can normally use a stepladder to reach shorter ceilings (such as in an office); however, you must then consider whether to survey with low-profile antennas that are not intrusive in the environment. In contrast, a 35-foot-high warehouse ceiling might require you to use a lift to reach the top to mount equipment for the site survey.

Ceiling construction The ceiling construction factors into consideration the type of antenna to use at a facility (and, therefore, what type of antenna the surveying technician needs to use). For example, low-profile diversity ceiling-mount omni-directional antennas are appropriate in drop-tile ceiling areas, and medium-gain omni-directional antennas are typically appropriate for a warehouse ceiling. Protruding medium-gain antennas in environments with low-height, drop-tile ceilings are at risk of being struck or even damaged.

Lift availability If a lift is not on site for high-ceiling work, you must rent one prior to the survey date to ensure its on-time delivery. Remember, safety first! The person using the lift should be both comfortable and trained with the type of lift and use applicable safety equipment. Some locations require a union worker to operate lifts.

Plenum ceiling If the ceiling is plenum rated, you might have to take extra steps during the site survey process to find alternative equipment-mounting locations. The AP as well as cables and antennas might need a plenum rating, too.

Wall construction Propagation is affected by the obstacles in the path between the client device and the AP, so it is helpful to know whether the wall construction is simple sheetrock or whether it is of a material that makes propagation difficult (such as plaster over metal lathe). If the latter, set expectations with the customer regarding propagation and a plan for higher number of potential APs (before the technician deploys to the site).

Current percentage of stock level Stock levels vary in warehouse environments, and so networks are designed to incorporate this as much as possible; however, the ever-changing environment can cause "dead" spots of no coverage. If stock levels are far below usual, a conservative survey should be done to anticipate coverage for a full warehouse by reducing power of an AP and raising acceptable thresholds of the diagnostic tests.

Temperature ranges Temperatures at a site might vary from extremely hot to extremely cold. Exposure to temperature extremes is a factor to consider (with regard to the survey engineer and the survey gear). Again, remember, safety first. Prepare for extreme exposure, no matter whether it is a cold freezer or ceiling work in a hot warehouse during summer months.

Hazardous areas Identify any areas that might be hazardous. Certain areas such as painting facilities or chemical factories might require special equipment to prevent fires or explosions. Once more, safety is a primary concern.

If the facility has hazardous areas, brush up on your material safety data sheets (MSDS) regarding the hazardous materials. Also have other safety equipment prepared for physical hazards, such as electrical shock or falling objects. You might require additional safety equipment, such as grounding straps or electrical insulators, safety harnesses, and even biological suits with respirators. Before working in a hazardous environment, be sure to take time to understand the hazards and preventive measures as well as the emergency-response conditions.

Survey Personnel Requirements

The customer might place certain requirements on you before you are permitted to enter or work in a given facility. In some cases, you might need protective clothing such as steel-toed shoes, hardhats, or hairnets. You might need to meet prerequisites such as drug testing, background checks, or security clearances. Be certain to verify any such issues with the point of contact at the facility before scheduling any work.

Scope of Work

The scope of work section details exactly what the survey engineer will do and what he will need to complete a proper job. This section of the pre-site survey form includes information such how the survey will be completed, how the engineer will mount antennas and APs, whether ceiling tiles will be moved, and so on. Anything that might cause disruptions to the production environment is vital and should be spelled out in detail. In addition to the details contained in the sample survey and scope of work, there should be a description of applications and the client devices that will be used with the WLAN. This section is one portion of the pre-site survey form in which you, as the survey engineer, provide feedback to the customer.

Coverage Map

As part of the pre-site survey form, develop a floor plan showing coverage areas and areas that the customer has defined as no-coverage areas. The coverage map indicates to the customer, the installer, and a troubleshooter the areas the system is designed to cover. Figure 6-1 shows a simple coverage map.

Outdoor Bridge Links

Chapter 14, "Outdoor Bridge Deployments":

ground obstructions is usually the best option. If the customer does not have roof rights in a building where space is rented, a suitable wall or inside window mount might be required.

Building exterior construction Some buildings are constructed in such a way that the construction actually limits how a technician can install equipment. To protect certain décors, a technician might have to find a nonintrusive way to install equipment. If the exterior is corrugated metal or highly reflective metal-oxide tinted glass, the bridge might suffer from reflection and multipath mitigation issues. A technician must install the bridge in such a way that this is not an issue for LoS bridging. Non-LoS (NLoS) bridging uses the multipath and reflection in an urban environment as part of the functionality.

Roof access Because basic short-range bridging is best done from the highest elevation possible, roof access to a building that is to be part of the bridge is desirable. Also determine whether roof penetration (the ability to pass the necessary cable through the roof) is already in place. Otherwise, the roof will need to have appropriate passages cut.