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The OpenAir Specification
The OpenAir standard describes a set of wireless protocols used by frequency hopping
spread spectrum devices that operate in the 2.4 GHz frequency band at a data rate of
1.6 Mbps.
An OpenAir radio changes its operating frequency several times a second. The order in
which an OpenAir changes frequencies is known as a hopping pattern or Channel.
The OpenAir standard specifies 15 non-overlapping Channels for operation. These
Channels are orthogonal: any two Channels are guaranteed to overlap only once during
a hopping cycle. Therefore, Access Points configured for different Channels will not
interfere with each other, even when operating in close proximity. The OpenAir
operating parameters are described in Chapter 4.
Roaming Between Harmony OpenAir Access Points
If there are multiple Harmony OpenAir Access Points on the network, then a mobile
client may seamlessly roam from one Access Point to another.
Each Access Point creates its own wirefree cell or coverage area. This is also known as
a Basic Service Area (BSA). A mobile device can communicate with a particular
Access Point if it is within the Access Point's coverage area.
If the cells of multiple Access Points overlap, then the mobile client may switch from
one Access Point to another as it travels throughout the facility. During the hand-off
from one Access Point to another, the mobile client maintains an uninterrupted connec-
tion to the network. This is known as "roaming."
Multiple Access Points connected to a common Ethernet network form an Extended
Service Area (ESA). All members of an Extended Service Area are configured with
the same Domain number and the same Security ID.
Mobile clients must be configured with the same Domain and Security ID as the
Access Points on the network; a client can only roam between Access Points that share
the same Domain and Security ID.
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