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724-746-5500 | blackbox.com
Chapter 2: Preparing for a WAN Deployment
The following are some quick hints for deploying access points:
• Standard sheetrock walls and dropped ceilings are the best locations for mounting access points.
• When deploying WLANs in retail stores, doing a site survey at each store is likely to be impractical. It is more common to run
detailed site surveys at a few locations and use the results to set up User Guidelines for the remaining sites.
• Be aware of metal-lined firewalls, steel pillars, and other metallic surfaces. RF signals can reflect off metal surfaces, which can
cause unexpected coverage patterns. Also watch out for objects that can block or reflect signals, such as mirrors, plants, walls,
steel doors, elevator shafts, and bathroom stalls.
• The quality and performance of a Wi-Fi network is a function of the signal-to-noise ratio. To avoid noise issues, check the area
for common noise generators such as industrial microwave ovens, wireless video cameras, cordless phones and headsets, and
Bluetooth devices. Such devices especially cause interference in the 2.4-GHz spectrum.
• Plan appropriately for high ceilings. With an omnidirectional antenna, the downward coverage is not great. In normal office
space, the ceilings rarely exceed 15 feet, so this issue does not come up very often. In environments such as warehouses, where
ceilings can be up to 50 feet high, ceiling-mounted access points are not optimal. It is best to deploy them on non-metallic walls
about 10 feet to 15 feet above the floor. If this is not feasible, using patch antennas can help direct the RF energy downward.
• In high-density or high-capacity environments, placing access points on exterior walls allows for a greater number of cells inside
the building and more capacity. In other deployments, it is recommended that the outer access points be no farther than
30 feet from the exterior walls to ensure coverage.
2.2.7 Preparing the Wired Network for Wireless
One of the advantages of moving to a Black Box WLAN is that you do not have to make changes to the underlying network, such
as putting controllers into wiring closets. This can save you considerable time and effort during installation. However, some
network changes might make sense for some deployments. For example, you might want to add additional VLANs or security
settings. This section covers a few of the more common considerations that IT departments are handling.
• 802.1Q VLANs
SmartPath APs can segment users into VLANs if an administrator wants. This decision can be made by a returned RADIUS attri-
bute or it can be configured as part of a user profile or SSID. Enterprises often set up separate VLANs for wireless and guest
access, so that this traffic is segmented from the rest of the network; however, it is possible to set up any number of other
VLANs for further segmentation.
• Firewalls
Depending on the environment, enterprises might use firewalls to segment wired and wireless data. This can be implemented
as a discrete firewall enforcing traffic between VLANs or between ports, or you might use the stateful firewall that is integrated
in SmartPath OS (the SmartPath AP operating system).
• RADIUS Authentication
If RADIUS authentication is required, then a RADIUS server must be in place and be able to support the necessary protocols for
wireless—often called 802.1X EAP types: PEAP, EAP-TLS, EAP-TTLS, WEP 8021.x (dynamic WEP), LEAP, EAP-FAST, and captive
web portal authentication using CHAP.
• DNS and DHCP Configuration
If you use the SmartPath EMS VMA (see Section 2.3, Operational Considerations), it is possible to install SmartPath APs without
any extra configuration and they will be able to contact SmartPath EMS VMA for management. If the SmartPath APs are linked
to a different subnet than the one to which SmartPath EMS VMA is connected, then you can set either a DHCP option or DNS
entry to give the location of SmartPath EMS VMA (see “How SmartPath APs Connect to SmartPath EMS VMA” in Section 8.4,
Example 4: Connecting SmartPath Units).
