|
I believe most if not all of the below are features
not found among Trango or Canopy. I list a few of the advanced features. A few
of these (probably some you have never heard of before or even thought of) I
show in detail. Maybe this post will also explain why the VL is not simply an
Atheros chipset in a case and why it is not simply some basic CSMA/CA. This is
just a small sampling. The manual, with lots of tables, drawings, etc., is 277
pages of which most relate to things that can be configured/optimized. (I can
send the pdf to any who want it.) ·
Chassis-based or stand alone AUs
with multiple LEDs on the chassi blade versions, including current consumption ·
Redundant power supplies with
status LEDs, including over temperature warning ·
GPS-sync module (for hoppers) also
can be used for VL for their alarm capabilities ·
110vAC or -48vDC power options ·
Built-in Ethernet repeater in the
chassis blades to support over 600 feet from network switch/router to ODUs ·
AUs with antenna options,
including built-in 60, 90, or 120 degree sectors plus options with external
connector ·
OFDM (with FEQ) for NLOS ability
to enable connection of more of the potential subscriber population ·
Adaptive modulation with
configurable minimum modulation ·
Up to 40Mbps net (ftp) per sector ·
Over 40,000pps with small packets ·
No loss in capacity with varying
frame size (all other UL gear capacity is dramatically reduced when passing
small packets ·
FIPS 197 option. AES standard, no
extra charge ·
Virtual LANs based on IEEE 802.1Q
with standard QinQ built-in support ·
Layer-2 traffic prioritization
based on IEEE 802.1p and layer-3 traffic prioritization based on either IP ToS
Precedence (RFC791) or DSCP (RFC2474). It also supports traffic prioritization
based on UDP and/or TCP port ranges. In addition, it may use the optional
Wireless Link Prioritization (WLP) feature to fully support delay sensitive
applications, enabling Multimedia Application Prioritization (MAP) for high
performance voice and video. (MAP can increase VoIP capacity by as much as
500%) ·
Built-in surge suppression in both
ODU and IDU ·
Full management of all components,
from any point in the system. ·
Components can be managed using
standard management tools through SNMP agents that implement standard and
proprietary MIBs for remote setting of operational modes and parameters. Security
features incorporated in BreezeACCESS VL units restrict access for management
purposes to specific IP addresses and/or directions, that is, from the Ethernet
and/or wireless link. ·
True toll quality VoIP (MOS of 4.1
or better) ·
Upload new or updated
configuration file to multiple (selectable) units simultaneously, thus
radically reducing the time spent on unit configuration maintenance. ·
Back up/shadow flash, can support
two different versions of firmware ·
5MHz (4.9GHz version), 10MHz, or
20MHz channel options. ·
SUs autorecognize and configure channel
size ·
SUs available with external
connector or integrated 21dBi with 10.5h/10.5v beamwidth ·
Multilevel password, multi-layer
ESSIDs ·
Configuration of remote access
direction (from Ethernet only, from wireless link only or from both) ·
Configuration of IP addresses of
authorized stations ·
Numerous LEDs detailing advanced
status information, plus tri-color 10-bar alignment LEDs that directly
corresponds to SNR, including amber for warning signal is too strong (SNR
>50dB) ·
Pole mount or band strap mounting
options, hardware included ·
Power supply included, with reset
feature and integrated surge suppression ·
Specialty Cat 5 connector ·
Industrial grade waterproof seal
with O rings ·
Auto or configurable maximum cell
distance ·
Automatic distance learning. Per
SU Distance Learning mechanism controlled by the AU enables each SU to adapt its
Acknowledge timeout to its actual distance from the AU, minimizing delays in
the wireless link ·
Low Priority Traffic Minimum
Percent feature ensures a selectable certain amount of the traffic is reserved
to low priority packets to prevent starvation of low priority traffic when
there is a high demand for high priority traffic. ·
MAC address deny and allow list ·
Able to configure size of
concatenated frames (enables customization/optimization based on expected
applications) ·
Best AU and preferred AU options
in the SUs. (Best AU explanation: each of the AUs can be given a quality mark
based on the level at which it is received by the SU. The SU scans for a
configured number of cycles, gathering information from all the AUs with which
it can communicate. At the end of the scanning period, the SU reaches a Best AU
decision according to the information gathered. The AU with the highest quality
mark is selected as the Best AU, and the SU will immediately try to associate
with it. The quality mark given to each AU depends on the level at which it is
received by the SU. The Best AU selection mechanism can be overridden by
defining a specific AU as the preferred AU.) ·
Broadcast rate limiting,
selectable ·
Configurable threshold for lost
beacon watchdog ·
Support of packet sizes to 1600
bytes, including VLAN(s) for single or double-tagged packets ·
Advanced event log feature. The
event log is an important debugging tool and a flash memory sector is dedicated
for storing it. Events are classified according to their severity level: Message
(lowest severity), Warning, Error or Fatal (highest severity). The severity
level of events that should be saved in the Event Log is configurable. Events
from the configured severity and higher are saved and may be displayed upon
request. Log history can be displayed up to the full number of current active
events. In the log, an event is defined as active as long as it has not been erased
(a maximum of 1000 events may be stored). The Event Log may be read using TFTP,
with remote file name <SNMP Read Community>.log (the default SNMP Read
Community is “public”). The Event Log may also be uploaded to a remote
FTP server. The Event Log Menu includes the following options: Event Log Policy,
Display Event Log, Erase Event Log, Event Load Upload ·
Multiple DHCP options: From
Wireless Link Only, From Ethernet Only, From Both Ethernet and Wireless Link ·
Intelligent ATPC (The algorithm is
controlled by the AU that calculates for each received frame the average SNR at
which it receives transmissions from the specific SU. The average calculation
takes into account the previous calculated average, thus reducing the effect of
short temporary changes in link conditions. The weight of history (the previous
value) in the formula used for calculating the average SNR is determined Menus
and Parameters Operation and Administration by a configurable parameter. In
addition, the higher the time that has passed since the last calculation, the
lower the impact of history on the calculated average. If the average SNR is
not in the configured target range, the AU transmits to the SU a power-up or a
power-down message. The target is that each SU will be received at an optimal
level, or as high (or low) as possible if the optimal range cannot be reached
because of specific link conditions. Each time that the SU tries to associate
with the AU (following either a reset or loss of synchronization), it will
initiate transmissions using its Transmit Power parameters. If after a certain
time the SU does not succeed to synchronize with the AU, it will start
increasing the transmit power level. In an AU the maximum supported transmit
power is typically used to provide maximum coverage. However, there may be a
need to decrease the transmitted power level in order to support relatively
small cells and to minimize the interference with the operation of neighboring
cells, or for compliance with local regulatory requirements. In some cases the
maximum transmit power of the SU should be limited to ensure compliance with
applicable regulations or for other reasons. ·
And ATPC is highly configurable
(only highly advanced operators should do so), with parameters like: ATPC min. SNR
level, ATPC Delta from min. SNR level, Min. interval between ATPC messages, ATPC
power level change step (1-20dB with default of 5dB) ·
Advanced Transmit Control. The Tx
Control option enables turning Off/On the AU’s transmitter, or having the
AU Tx status controlled by the status of the Ethernet port/link. ·
Cell Distance Mode feature: The
higher the distance of an SU from the AU that is serving it, the higher the time
it takes for messages sent by one of them to reach the other. To ensure appropriate
services to all SUs regardless of their distance from the AU while maintaining
a high overall performance level, two parameters should be adapted to the
distances of SUs from the serving AU: The time that a unit waits for a response
message before retransmission (ACK timeout) should take into account the round
trip propagation delay between the AU and the SU (The one-way propagation delay
at 5 GHz is 3.3 microseconds per km/5 microseconds per mile.). The higher the
distance from the AU of the SU served by it, the higher the ACK timeout should
be. The ACK timeout in microseconds is: 20+Distance (km)*2*3.3 or 20+Distance
(miles)*2*5. To ensure fairness in the contention back-off algorithm between
SUs located at different distances from the AU, the size of the time slot
should also take into account the one-way propagation delay. The size of the
time slot of all units in the cell should be proportional to the distance from
the AU of the farthest SU served by it. The Cell Distance Mode parameter in the
AU defines the method of computing distances. When set to Manual, the Maximum
Cell Distance parameter should be configured with the estimated distance of the
farthest SU served by the AU. When set to Automatic, the AU uses a special
algorithm to estimate its distance from each of the SUs it serves, determine
which SU is located the farthest and use the estimated distance of the farthest
SU as the maximum cell distance. The value of the maximum cell distance parameter
(either computed or configured manually) is transmitted in the beacon messages
to all SUs served by the AU, and is used by all units to calculate the size of
the time slot, that must be the same for all units in the same sector. When the
Per SU Distance Learning option is enabled, the AU uses the re-association
message to send to each SU its estimated distance from the AU. The per-SU
distance is used to calculate the ACK timeout to be used by the SU. When the
Per SU Distance Learning option is disabled (or if it cannot be used because
the SU uses a previous SW version that does not support this feature), the SU
will use the maximum cell distance to calculate the ACK timeout. The AU always
uses the maximum cell distance to calculate the ACK timeout. It should be noted
that if the size of the time slot used by all units is adapted to the distance
of the farthest unit, then no unit will have an advantage when competing for
services. However, this reduces the overall achievable throughput of the cell.
In certain situations, the operator may decide to improve the overall throughput
by reducing the slot size below the value required for full fairness. This
means that when there is competition for bandwidth, the back-off algorithm will
give an advantage to SUs that are located closer to the AU. The Cell Distance
Parameters menu includes the following parameters: fairness factor, per SU distance
learning, show cell distance parameters. ·
Arbitration Inter-Frame Spacing
feature ·
Max association feature ·
Wireless Link Trap Threshold feature:
defines the threshold for the wireless quality trap, indicating that the
quality of the wireless link has dropped below (on trap) or has increased above
(off trap) the specified threshold. The Wireless Link Trap Threshold is in
percentage of retransmissions, and the allowed range is from 1 to 100 (%). The
default is 30 (%). ·
Lost Beacons Transmission Watchdog
Threshold feature: When it is unable to send beacon frames for a predetermined
period of time, such as in the case of interferences, the AU resets itself. The
Lost Beacons Transmission Threshold parameter represents the number of
consecutive lost beacons after which the unit will reset itself. The range for
this parameter is 100 – 1000 or 0. When the parameter is set to 0, this
feature is disabled, i.e. internal refresh will never be performed. The default
value is 218. ·
Disassociate (AU only) feature:
enables disassociating all SUs associated with the AU or a selected SU. This
feature is useful during configuration changes, enabling to force the SU(s) to
re-initiate the association process, including the search for the best AU (or a
preferred AU) using the Best AU process, without performing a full reset. The
Disassociate submenu includes two options: Disassociate All SUs, Disassociate
SU By MAC Address: to disassociate a selected SU. ·
Configurable Minimum and Maximum Contention
Windows (The BreezeACCESS VL system uses a special mechanism based on detecting
the presence of a carrier signal and analyzing the information contained in the
transmissions of the AU to estimate the activity of other SUs served by the AU.)
The available values are 0, 7, 15, 31, 63, 127, 255, 511 and 1023. A value of 0
means that the contention window algorithm is not used and that the unit will attempt
to access the medium immediately after a time equal to DIFS. The default min. value
is 15. The default max. is 1023. ·
Advanced MIR/CIR (controlled by
both the SU and AU) with special configurable graceful degradation algorithm ensuring
that the degradation of performance for each individual SU is proportional to
its CIR. Patrick Leary AVP WISP Markets Alvarion, Inc. o: 650.314.2628 c: 760.580.0080 Vonage: 650.641.1243 ************************************************************************************ This footnote confirms that this email message has been scanned by PineApp Mail-SeCure for the presence of malicious code, vandals & computer viruses. ************************************************************************************ |
-- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless
Archives: http://lists.wispa.org/pipermail/wireless/
