airaya_competition.pdf

8/14/2019 Airaya_competition.pdf

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2009 Redline Communications Inc. www.redlinecommunications.com

Airaya Competition


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2 2009 Redline Communications Inc. www.redlinecommunications.com

Airaya (802.11n) Systems

802.11 Products were designed for indoor wireless LANs. The

802.11 protocol trades off lower throughput and higher latency toachieve reliable indoor connectivity.

802.11n products have fundamental weaknesses compared to AN-80i

Design distances are less than 300 meters

802.11 uses a contention based protocol which cannot guarantee quality of

service In addition, throughput and latency are highly impacted by interference and

packet size

PMP is generally not available in outdoor products, and is even more susceptible

to interference than the PTP versions

Security requirements are not as stringent

The volumes of outdoor wireless products are tiny compared to the volumes of

indoor wireless products. Therefore, chipset makers do not concern

themselves with the support issues specific to outdoor products.

Redlines AN-80i chipset is purpose built for high performance

outdoor wireless connections.


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Problems with Airaya (802.11n) Designs

802.11 products are build on a chipset designed for 300 m range

The 802.11 protocol is build with internal timing that assumes the longest

distance between transmitter and receiver is 300 m

Some vendors extend the timer to fix this problem, but at the expense of

performance at longer ranges

Complex software changes are be required to improve protocol efficiency at

longer range

The 802.11 protocol is very sensitive to interference 802.11n radios switch to Rx mode immediately after Tx

As a result if any interference is present the unit will miss an acknowledgement

with severe performance implications

Latency will typically increase by 600% in the presence of interference

There is no solution for this issue for users of 802.11 chipsets


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A contention based MAC cannot provide consistent performance

The 802.11 design sacrifices performance to achieve connection

Latency and throughput cannot be guaranteed as the 802.11 protocol as over-

the-air-packets are not scheduled.

Performance in the presence of interference can become severely inconsistent

Limited frequencies and channel widths

Typically the chipsets only support 4.9-5 .8 GHz

Typically only 20 and 40 MHz channel widths are supported

Redline supports 5, 10, 20, and 40 MHz channel widths at 4.9-5.8 GHz

Redline supports 3.3-3.8 GHz in 3.5, 5, 7, 10, 14 and 20 MHz channel widths

Poor small packet performance

Vendor claims usually assume large packets However 802.11n small packet performance will be as low as 1/10 to 1/20 of the

specified performance

This is a HUGE impact on VoIP

AN-80i throughput for large or small packets is virtually unchanged


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Chips use build in radios designed for indoor LANS

802.11 chipsets provide lower power output

Some manufacturers add external radios to improve RF quality

Redlines AN80i radios are purpose built for outdoor use, and output up to 25

dBm of power

Limited security

802.11n Chipsets have not been designed meet the most stringent security

measures

Redlines AN-80i is designed to meet the FIPS-140-2 standard

Limited QoS Quality of Service

802.11n products use a contention based protocol which cannot guarantee

minimum performance.

QoS features (such) as minimum information rate and peak information rate are

typically not available


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Advantages of the Redline AN-80i

Excellent Low Latency Less than 1 ms in PTP mode

Less than 6 ms in PMP mode

Latency is typically 1-3 ms even in the presence of interference, while 802.11n

designs will exceed 12 ms in the presence of interference

High Quality Packaging

IP 67 submergible rated keeps the humidity out Temperature ranges from -40 to +60 degrees C

Point to Multipoint

Up to 30 subscribers can share a single PMP master station

Support for More Frequencies 3.33.8 Licensed Bands

3.65 GHz Light Licensed Bands (USA)

4.9 Public Safety USA

4.9-5.3 GHz, 5.4 and 5.8 GHz Licence Exempt Bands


7/117 2009 Redline Communications Inc. www.redlinecommunications.com

Advantages in the Redline AN-80i (contd)

Dynamic TDD

AN-80i rapidly adjusts upstream and downstream TDD ratios for greatly

improved real world performance.

Dynamic ARQ

The AN-80i adjusts modulation levels on a packet by packet basis

Resent packets are configured to a slightly more robust level of Modulation

Some competitive products only jump down to the lowest level of Modulation

Support for Multiple Hops

AN-80i is VERY GOOD at multiple hops. Current installations have up to 7

hops with low latency

802.11 and mesh dramatically reduce throughput and high latency per hop.

An-80I HAS Management Features Ideal for Outdoor Use

Diagnostic Tools

NMS Support



Performance Chart AN80i vs. 802.11 (n, a/g)

Performance Features AN-80i 802.11a/g 802.11n

2x2Dynamic Adaptive TDD Yes No No

Scheduled MAC Yes No No

Rx sensitivity, dBm -87 @6Mb/s

-84@12 Mb/s

-65@108 Mb/s

-86 @6Mb/s

-83@12 Mb/s

-66@108 Mb/s

-88 @6Mb/s

-83@15 Mb/s

-67@150 Mb/s

Total RF power @ 5 Ghz, dBm -25 @6Mb/s-23@12 Mb/s

-18@108 Mb/s

-20 @6Mb/s-20@12 Mb/s

-15@108 Mb/s

-25 @6Mb/s(for enhanced

products)

Supported Bands GHz 3.3-3.8 4.9-5.8 2.4, 4.9-5.8 2.4, 4.9-5.8

Channelization @5 GHz 5, 10, 20, 40 20, 40 20, 40

Max Bit Rate at MAC output

1514-byte packets, Mb/s88 27 270

Max Bit Rate at MAC output

64-byte packets, Mb/s87 1 22-44

Latency, 20 MHz channel, no

interference



Feature Comparison AN80i vs. Airaya

Features Comparison

Airaya Wireless GRID AN80iPrice (min/max)

Ethernet Rate (min/max) 1/108 Mbps 4.5/108 Mbps

Price / bit

Frequency Range 4.9, 5.4 or 5.8 4.9, 5.4, 5.8 or 3.5

Latency 1-2 msec 1 msec

Output Power 21 dbm 25 dbm

Channel Size 5,10,20 & 40 MHz 5,10,20 & 40 MHz

Configuration

PTP & PMP on different

Hardware(radio)

PTP & PMP on same

Hardware(radio)

Modulation OFDM OFDM

Adaptive Modulation Yes Yes

Duplexing TDD Fixed Dynamic TDD

Spectrum Analyzer No YesSecurity AES 128/WEP 152 FIPS 140-2 AES 256

Interface Prop. PoE IEEE 802.3 af - PoE

Power Consumption >20 W < 15 W

Wireless Frame & ARQ Fixed Dynamic

DFS No Yes

Operating Temperature -20 to 55 deg. C -40 to 60 deg. C



Key Counters Against Airaya

Fixed TDD & Frame architecture. Not suitable for real timeservices, whereas dynamic TDD & Frame architecture in AN80i

makes it ideal for real time services (Video Surveillance, VoIP,

TDM etc.)

AN80i has very high PPS (Packet per second) capability (FPGAbased radio) making it an ideal solution for real time applications

i.e. Video Surveillance.

Fixed TDD results in poor spectral efficiency. Their 108 Mbps is

two way implying 54 UL & 54 DL (54 Mbps effective), whereas

AN80i has Dynamic TDD which gives 90 Mbps one way (on

demand basis).



Key Counters Against Airaya (contd)

Low TX Out results in lower link margins and distances.

No dynamic ARQ results in high probability of errors in noisy

conditions.

Absence of spectrum analyzer, makes it harder to have stable link

operation in Un-licensed environment.

Non-standard PoE introducing another box in the network.

High power consumption whereas AN80i has only 15.4 Watts of

consumption, making it ideal to be used without adding much into

the existing power infrastructure.

airaya_competition.pdf

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