Installation guide

102
Wi-Fi Location-Based Services—Design and Deployment Considerations
OL-11612-01
RFID Tag Considerations
PanGo Locator LAN Asset Tags
PanGo version 1 Locator LAN asset tags (www.pangonetworks.com) are intelligent 802.11 active RFID
devices that interact directly with the Cisco LBS solution as WLAN clients. These motion-sensitive asset
tags are 3.5” x 2.6” x 1.1” in size and are powered by two commonly-available 1.5 volt “AA” size lithium
batteries. Being a motion-sensitive asset tag, battery life is highly dependent on movement but is rated
by the manufacturer at approximately 8000 transmissions in normal usage. Typical weight of the
version 1 Locator LAN asset tag is 4.9 ounces including batteries (see Figure 75).
Figure 75 PanGo Locator LAN Tag (Version 1)
These asset tags have an integrated 802.11b transceiver that PanGo Networks specifies can deliver a
maximum of +16dBm transmitter output power. It is a motion-sensitive active RFID tag that accesses
the WLAN infrastructure as a full WLAN TCP/IP network client. The asset tag associates to the WLAN
infrastructure in the same way as a normal mobile 802.11b laptop or PDA (see Appendix D—PanGo
Locator LAN Tag Association and Signaling, page 117 for a packet trace summary). Each Locator LAN
tag acquires an IP address via DHCP to communicate with the PanGo location client. Supported 802.11b
data rates are configurable as well as any number of channels from 1 through 11. Version 1 Locator LAN
asset tags require the mandatory use of either 40-bit or 128-bit static WEP with the WEP key defined in
WEP key index 1.
The Cisco LBS solution detects these tags as WLAN clients with the Cisco WCS displaying their
location on floor maps as blue rectangles (see WLAN Clients, page 25). Other applications interfacing
to the location appliance via the SOAP/XML API (such as PanGo Locator Monitor) use a different icon
set to display more detail about the state of the tag (stationary or in motion) as well as the asset to which
the tag is attached.
The Locator LAN tag uses an advanced power management system that allows the tag to communicate
to its supporting application system only as needed. It is not necessary for the PanGo Locator LAN tag
to beacon constantly at a fixed rate. In fact the LAN Locator tag has multiple configurable transmission
intervals which have a direct relationship to the current motion status of the tag. The detection of motion
triggers the tag to change its transmission behavior as it transitions from the stationary state to the mobile
state. As the asset and the attached tag come to rest, the tag modifies its behavior once again as it
transitions from the mobile state back to the stationary state. Transmission behavior is controlled via
individual reporting interval properties that are specified in the tag configuration profiles in the PanGo
location client. When not in motion, the default reporting interval for the tag is 21600 seconds or 6 hours,
which can be re-configured via the tag profile settings.
Although PanGo version 1 Locator LAN asset tags have an integrated serial interface that is accessible
without opening the case, this is used mainly for tag debugging. There is no need for a physical
connection to the tag to perform initial tag configuration. Rather, version 1 tags are initially configured
over-the-air (OTA) using an access point set temporarily to the tag’s factory default values for SSID and
WEP key and a special “broadcaster” application installed on the PanGo PanOS server. Once initially
configured in this manner, PanGo Locator LAN asset tags can be re-programmed from the main WLAN