1. What are BeamFlex and SmartCast?
They are patent-pending smart antenna and RF traffic engineering
technologies (respectively) embedded into every Ruckus system.
BeamFlex is MIMO smart antenna technology and represents
the industry’s most advanced multiple input/multiple output
(MIMO) antenna implementation of its kind. It combines a compact
internal antenna array with expert system control software.
The result is an intuitive Wi-Fi system that continuously ranks
the best antenna pattern for each receiving device, constantly
reconfiguring itself in real-time as interference is encountered.
BeamFlex steers RF signals around interference to eliminate
Wi-Fi dead spots while increasing the range and performance
of the Wi-Fi network.
SmartCast is a very sophisticated traffic inspection and
classification engine that provides a number of unique functions
such as remote RF monitoring, quality of service and application-aware
content parsing. SmartCast ensures that different traffic types
are each handled according to their specific requirements.
Combined, SmartCast and BeamFlex provide the predictable
performance needed for picture-perfect multimedia content delivery.
2. Can’t I just use any Ethernet-equipped access point and
adapter for Wi-Fi video?
While it is possible to use off-the-shelf APs and adapters
for wireless video streaming at very short distances (less than
20ft / 6m), most homes and apartments do not benefit from such
conditions. Most urban home environments are very “noisy” with
microwave ovens, cordless phones and neighbor Wi-Fi noise –
all of which introduce interference and degrade wireless transmissions.
In turn, off-the-shelf wireless solutions aren’t suitable for
IPTV over Wi-Fi. This has been the central problem that has
plagued Wi-Fi from being the universal networking infrastructure
for all voice, video and data communications in the home. Ruckus
has solved this exact problem.
3. Is BeamFlex a standards-based technology?
Yes. BeamFlex applies MIMO diversity techniques to standards-based
802.11 b/g technologies to eliminate dead spots, increase range
and performance for all standard 802.11b/g devices.
Any 802.11 b/g client station that associates with a BeamFlex
powered AP can instantly benefit from the increased range and
throughput, with no configuration changes required on the client.
Ruckus Wireless will extend BeamFlex support for other standards-based
802.11 technologies, including 802.11a and future 802.11n. Unlike
all other approaches, BeamFlex gives users all the benefits
of MIMO without the cost or complexity. BeamFlex overlays any
existing 802.11 chipset giving equipment manufactures complete
extensibility to future 802.11 technologies.
4. How does the BeamFlex technology work?
Each Ruckus product is equipped with a compact, internal
antenna array with six high-gain, directional antenna elements
capable of forming 63 unique antenna patterns for massive diversity.
The BeamFlex expert system control software continuously ranks
the optimum antenna patterns for each receiving device, using
the inherent feedback mechanism built into the 802.11 MAC layer
protocol. This knowledge enables the BeamFlex antenna array
to reconfigure itself in real-time, detecting and adjusting
for both spectral and multi-path interference as well as neighbor
network noise. By selecting the optimum antenna pattern for
each receiving device, BeamFlex enables better signal quality
and higher communications speeds over the 802.11b/g network.
The massive diversity of the BeamFlex antenna systems allows
Ruckus devices to find and instantly select from many quality
signal paths in a changing environment to sustain the baseline
performance required for audio and video applications. The BeamFlex
technology alone extends the range and throughput of standard
802.11b/g clients by 200 to 300 percent.
5. What is MIMO?
It’s the next generation of Wi-Fi. MIMO stands for multiple
input; multiple output. It’s an antenna technology for wireless
communications in which multiple antennas are used at both the
transmitter and the receiver. The antennas at each end of the
communications circuit are combined to minimize errors and optimize
data speed. MIMO generally operates in two modes: diversity
mode and spatial multiplexing mode.
In diversity mode, MIMO systems use multiple antenna arrays
to maximize range and throughput between two wireless devices
by choosing the best signal path between them. In spatial multiplexing
Mode, MIMO systems use multiple signal paths to simultaneously
transmit different data elements, where the receiver “recombines”
the signals and data elements, ideally resulting in higher throughput.
Spatial multiplexing requires industry standardization for multivendor
interoperability, while diversity methods can be implemented
on just one side of a communications link (for more detailed
information, please download our whitepaper on smart antenna
techniques).
6. Does the Ruckus support MIMO?
Yes. BeamFlex implements diversity mode but not spatial multiplexing
mode, which currently has not been standardized. We use multiple
antennas at each end to establish the best possible path at
any given time for any given packet. Implementing spatial multiplexing
mode today would require proprietary algorithms to be supported
on both the AP and the client stations to attain its benefits.
7. I’ve seen some new higher-speed Wi-Fi routers and adapters
that tout 108Mb/s, MIMO and Pre-N standard. How do the Ruckus
products compare?
802.11N is the next-generation standard for Wi-Fi. It is
currently in the early stages of standard development and a
draft standard is not yet available. The consensus in the industry
is that the standard will be finalized by late 2006/early 2007.
The point to remember is that sending video over Wi-Fi requires
much more than bandwidth and network capacity. It requires reliable
and predictable network characteristics. This is especially
challenging with Wi-Fi.
The current .11N proposals have centered on the use of MIMO
technologies to increase range and performance. However, there
are many modes of operation in MIMO and within each mode, many
options. Some of the MIMO techniques, such as spatial multiplexing,
requires changes to both the network and the client and must
be standardized to ensure multi-vendor interoperability. Other
techniques such as antenna diversity can be implemented on only
the network or the client side and be interoperable with all
standards-compliant devices in the same network.
Early “pre-N” or MIMO products that implement spatial multiplexing,
such as the Belkin Pre-N wireless router and notebook network
card, and the Linksys SRX MIMO router/access point and adapters,
require a dual-end solution, i.e., both the router/AP and the
client adapter from the same vendor must be used together to
deliver the promised benefits. Worst yet, their spatial multiplexing
algorithms are non-standard and will be obsolete when 802.11N
is available. Lastly, these products are optimized for managing
PC-centric data applications, not video applications.
The Ruckus approach is completely standards complaint. Our
BeamFlex technology, while providing the benefits of MIMO’s
diversity techniques, works within the 802.11b/g standard. With
the Ruckus AP, the range and performance advantages benefit
all 802.11b/g clients without any upgrades on the client side.
The Ruckus products are also tuned for video applications, with
innovative, advanced QoS and multicast IPTV extensions that
are not available in any other products in the market.
8. Why are the SmartCast QoS features necessary?
Off-the-shelf WLAN devices don’t differentiate between the
various traffic types (voice, video, data) on the network. All
traffic is created as equal, and thus the WLAN typically works
in a “first-come first-served” fashion. Frequently, it is the
PC-data clients transferring large files that capture much of
the bandwidth. Video applications require constant, uninterrupted
bandwidth. If video is transmitted while Internet surfing, email
access or downloads occur, the video quality will surely suffer.
Ruckus products incorporate a unique QoS approach for multimedia.
This SmartCast QoS optimizes traffic management algorithms to
ensure adequate, on-demand bandwidth for multiple broadcast
quality video streams while maintaining adequate bandwidth for
data applications. In turn, SmartCast QoS ensures a satisfactory
viewer experience.
9. Don’t I just need a higher-speed Wi-Fi product to make
IPTV / video work?
Not necessarily. Adding bandwidth to the Wi-Fi network will
not automatically enable wireless video distribution. Video
requires a consistent, low-delay availability of network bandwidth.
Newer WLAN technologies such as spatial multiplexing mode in
MIMO increases the wireless data rate but will not guarantee
bandwidth consistency. As radio signals ebb and flow (due to
motion or interference from Bluetooth phones, for example) and
other applications compete for the WLAN’s bandwidth, transmission
errors and delays will still occur.
10. Don’t I just need a Wi-Fi product that supports the
802.11e draft standard, or WMM (Wi-Fi Multimedia, a Wi-Fi Alliance
interpretability certification) to make IPTV / video work?
802.11e is intended for adding basic QoS features to IEEE
802.11 networks. WMM, which is based on the 802.11e draft standard,
prioritizes traffic according to four access categories: voice,
video, best-effort and background.
However WMM does not provide guaranteed throughput, nor does
it define any mechanism for automatically classifying traffic
into the four access categories. Products that support WMM typically
shift the burden to the user, requiring complex configurations
that are generally too challenging for a typical consumer. SmartCast
QoS automatically detects video and IPTV traffic and prioritizes
them according to bandwidth and delay requirements. In addition,
per-station queuing on Ruckus products provides much finer granularity
and higher precision for bandwidth prioritization compared to
other consumer Wi-Fi products in the market.
11. Is the Ruckus AP the same product as the Netgear RangeMax
Smart MIMO router, which is also based on Ruckus Wireless technologies?
NETGEAR’s RangeMax router only integrates Ruckus BeamFlex
technology and is positioned to extend the coverage and capacity
of Wi-Fi for use in data applications.
In other words, NETGEAR’s RangeMax router is optimized for high
performance data, not video. It does not support Ruckus SmartCast
technology.
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