User's Manual

Teklogix 9150 Wireless Gateway User Manual 91
Chapter 4: Access Point Configuration
IAPP Parameters
In IAPP Announce procedures, when the 9150 is initialized, it sends an IP multicast
message to inform the other 9150s in the network that it has become active. It also
informs the other 9150s of its continued operation (‘alive’ status) by periodically
multicasting the Announce beacon.
The Handover protocol is intended to inform the old 9150 that a terminal has been
associated with a new 9150, and to update the filter tables of intermediate MAC-
bridges to correctly forward frames destined for the terminal. The newly-associated
9150 sends a Handover request to the old 9150, which disassociates itself and
acknowledges the request.
Important: These parameters are set with optimum default values. Do not
adjust these values without discussing the effects with your Psion
Teklogix representative.
4.5.1 IAPP Parameters
Announce Period
The Announce Period parameter indicates the number of seconds between
Announce broadcasts. For further information, see “Mobility Configuration” on
page 90.
Handover Timeout
If there is no response to the Handover request by the 9150 within the time specified
in the Handover Timeout parameter, the request is retransmitted. If no response is
received after a number of retries (set in the Handover Retries parameter, below),
the 9150 will complete the reassociation procedure itself. For further information,
see “Mobility Configuration” on page 90.
Handover Retries
This parameter sets the number of times the 9150 will transmit a Handover request
to the disassociated 9150, before it completes the association transfer itself. See also
Handover Timeout, above.
Delay Double
The Delay Double parameter doubles the amount of Handover Timeout between
Handover Retries. For example, if the first retry is after 500 milliseconds, the next
Handover request is sent after 1 second, followed by a retry after 2 seconds, etc.