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NUCLEUS 802.11 STA
Nucleus 802.11 STA is an embedded
implementation of the IEEE 802.11 standards. What this means
for you is that it was developed with the requirements of the
embedded space in mind, rather than being a port of a product
that was originally optimized for PC's and workstations. It is
also extremely portable, and a new port of the Wireless LAN
driver can be developed with little effort.
The "STA" stands for station. There are two
types of 802.11 devices, Stations and Access Points. An Access
Point can be standalone, but is generally built into a
gateway, i.e., a device that moves data from the wireless
network to the wired network. A Station is an endpoint. A
station that we are all familiar with is a PC. In the embedded
world a station could be a digital camera, set-top-box,
television, cell phone, or a number of other consumer
electronics devices.
The Security component of Nucleus 802.11 STA
supports Open System and Shared Key Authentication schemes by
default as stated in the 802.11 specifications. This component
was designed to be highly modular, enabling the addition of
new, future, authentication models to be easily made. For
example, the security protocol for 802.11 is currently being
re-written by IEEE, known as 802.11i. The design of this
component will allow for easier integration with this new
protocol.
Nucleus 802.11 STA supports the following IEEE
specifications:
- 802.11 - 1999 - Wireless LAN Medium Access
Control and Physical Specifications
- 802.11a - 1999 - High-Speed Physical Layer
in the 5 GHz Band
- 802.11b - 1999 - Higher-Speed Physical
Layer Extension in the 2.4 GHz Band
- 802.11d - 2001 - Specification for
operation in additional regulatory domains
- 802.11g - 2003 - Further Higher Data Rate
Extension in the 2.4 GHz Band
It is important to note that Nucleus 802.11
STA has been written and tested against wireless Ethernet
chipsets supporting one or more of the above listed standards,
but for any given version of the driver the underlying chipset
defines which of these standards are possible.
Integrating Nucleus STA Into An Existing
System
Nucleus 802.11 STA was developed to work as a network driver
for Nucleus NET. Applications interfacing with Nucleus NET are
isolated from the underlying device driver and Nucleus 802.11
STA is no exception to this rule. The only requirement from
the application level is to initialize the 802.11 driver. From
that point the application is unaware of the underlying
network hardware. In addition to Nucleus NET, Nucleus PLUS is
a requirement for those wishing to utilize Nucleus 802.11.
However, if further control of the 802.11
device is required API services are supplied that allow more
flexibility. These services allow the application to
enable/disable WEP, set the WEP key, retrieve 802.11
statistics, scan for access points, and so on.
Conclusion
802.11 has become the standard for wireless
communications. While it originated within the desktop arena
the costs have fallen such that it is being widely deployed in
a variety of consumer electronics as well as other types of
embedded systems. The addition of Nucleus 802.11 STA to the
Nucleus family of products allows our customers to cost
effectively upgrade their future devices to support these
standards. We continue to monitor the 802.11 standards and
already have some of the newer addition on our roadmap for
future inclusion into the product. We will also be introducing
a 802.11 Access Point solution in the future.
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