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Municipal Surveillance
Solutions Using Wireless Video Mesh
Mesh for Video Surveillance
| Video
surveillance for anti-crime and counter-terrorism |
Video surveillance is fast becoming a key driver for wireless mesh
in metropolitan areas. Early installations in US cities have proven that surveillance reduces crime. Video over mesh will also be
used for counter-terrorism. Although the London surveillance system used older video technology, the London bombings of July
2005 showed how critical surveillance can be in identifying and locating terrorists. To expand outdoor video surveillance
networks in the future, wireless distribution is a must, and mesh technology provides the most flexible solution. The biggest
challenge is creating a mesh that delivers the high bandwidth and low latency/jitter required for high resolution, high quality video.
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| Mesh
for next generation video surveillance |
Video applications always require higher bandwidth than other
applications. While new compression techniques like MPEG4 and H.263/264 have greatly reduced the bandwidth required for video
transmission, there is always a desire for more resolution and sometimes higher frame rates. Capturing a clear view of a
suspect’s face may rely on just one video frame, and if the frame rate is too low, that frame may be missed. Resolution is also critical since the ability to enlarge
portions of a frame may make the difference in identifying a suspect or confirming an illegal act.
A wireless mesh offers further advantages. The wired data network in a metropolitan area is
relatively inflexible, often offering a limited choice of physical locations to connect to the high speed
wired backhaul that in turn connects to the surveillance Command and Control center. Using
wireless mesh enables a multi-hop topology to be established where the video packets can “hop
around” obstacles like buildings, hills, and trees, as they are relayed from one mesh router to
another.
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| Multi-hop
mesh challenges: bandwidth preservation |
The challenge is to carry the high bandwidth required for
video from hop to hop as the packets are relayed. Most mesh systems use only a single radio for performing this
relay function. When a single radio is used to relay packets, a simple physical limitation becomes evident -
one radio cannot do two things at once. A single radio relay must first receive a packet, which takes a certain
amount of time. Then the radio must re-transmit the same packet to pass it along to the next mesh
node. This re-transmission takes the same amount of time that it took to receive the packet.
Thus, the single radio relay operation takes twice as much time to process the packet with the net result
that the bandwidth may be effectively cut in half. This degradation then compounds from hop to hop. If the path through the mesh from a camera to
a wired connection goes through 4 hops, then each packet will be relayed 3 times. Thus, the
bandwidth will be effectively cut in half 3 successive times along the path. This can result in a
bandwidth transmission capability as low as (1/2)*(1/2)*(1/2), or (1/8) for this path. The actual
degree of degradation varies with the mesh topology and interference effects, however, it will
certainly reduce the video capabilities of a conventional 1-radio mesh to a noticeable extent as more
hops are added.
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| Multi-radio
mesh relays |
When mesh nodes are constructed to have a 2-
radio relay capability, the bandwidth is preserved from hop to hop. As a video packet is being
received by one relay radio, the other relay radio is simultaneously sending another packet onward.
Wave Wireless routers each have a single radio, but through their integral Ethernet ports and flexible
control software, can be integrated to build a mesh topology with multi-radio relays. Thus, two or
more SPEEDLAN routers from Wave Wireless can be used to create a single mesh node that has
very high performance characteristics. Performance is further increased since each router has its own processor.
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| Optimizing
node configurations for performance |
SPEEDLAN 9200 units are robust mesh routers with a built-in firewall as
well as encryption supporting WEP, WPA, and WPA2 (AES). They are also relatively low cost and enable different node configurations to be easily
constructed. For a video surveillance mesh, both simple and complex nodes are useful as shown here. Simple nodes include a single radio root
or base-station node, as well as camera-only nodes which are most prevalent in a surveillance mesh. Simple 2-radio relay-only nodes are
useful when a hop is especially long range and a camera is not required, and 2-radio nodes are also needed that consolidate video streams from
multiple camera nodes while also supporting a local camera.
More complex nodes are occasionally used at junctures where multiple functions like packet relay,
video stream consolidation, and local camera support are all required. Here it is useful to add a
network switch for flexibility. Today, such switches are small and low cost (~$100). In these
pictures, radios that perform video stream consolidation are shown with omni-directional (round icon) antennas. Sector
antennas may also be used for consolidation depending on the topology and placement of the cameras supplying the streams.
Sector antennas are seldom used with horizontal beam angles of more than 120 degrees, while an omni antenna can receive
packets from camera nodes at any location within 360 degrees. The most complex node shown here uses 3-radios with one for
consolidation and another for long distance relay from other camera clusters. With a local network switch included, it is also
easy to add one or more local cameras, especially if the cameras come with an integral Ethernet interface.
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| Building
a max performance video surveillance mesh |
Some surveillance applications are easily
addressed with a simple ad-hoc mesh architecture while other applications require
more complex architectural solutions. Wave Wireless SPEEDLAN products support both
approaches. If wired backhaul connections are relatively available, the mesh may only require
a maximum of one or two hops. For these, the
simple architecture shown here will often be adequate, and any bandwidth degradation due
to the single radio relay will be minimal. For more demanding applications, the following
pictures show how a variety of different mesh node configurations may be integrated into a
max performance video surveillance mesh. The root or base-station node may be a single radio with an
omni-directional antenna, or for more performance may include multiple radios, each with its own sector antenna covering a portion of the entire
360 degree horizon.
The RF links shown in red are assumed to be relatively long distance and represent relay links
between camera clusters. The environment for each surveillance installation is
different. The wired backhaul that provides the final connection back to Command & Control may be readily available or may only exist at a
considerable distance from the surveillance area. There may or may not be a requirement for a
camera at a relay node location. The most important thing to notice in the max performance topology shown here is that at no time
does a video packet travel through a 1-radio relay. The bandwidth is preserved at all nodes and the
video performance is maximized. Notice also that the most prevalent type of mesh node in the
system will be a 1-radio node with camera-only, thereby keeping the overall cost low.
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| Lower
total deployment cost |
Wave Wireless SPEEDLAN 9200 mesh routers are engineered as industrial grade and are also
reasonably priced. In fact, they are currently priced at about half the cost of units from some mesh
suppliers, enabling two SPEEDLAN routers to be purchased for the same price as one from another
supplier. In a video surveillance mesh, more than half the nodes will be camera-only, requiring only
one mesh router. Some nodes that perform consolidation will require two routers, and a few that
perform more complex functions (like combining consolidation and relay) will require three. Overall,
in a mesh such as that described here, the typical number of routers per node will be less than two
probably around 1.5 on average. Also, SPEEDLAN routers are typically sold without antennas,
which means that in addition to choosing the best antenna for the specific link, customers get
additional savings since they may buy direct from the antenna supplier without additional markup.
The biggest savings relative to other suppliers, however, results from the flexibility in deployment
density provided by SPEEDLAN routers. Conventional 1-radio mesh routers that support only
omni-directional antennas suffer from limited range. This can force routers to be deployed at relatively
short distances from each other even when the needs of the application don’t require it
forcing the customer to buy more routers than necessary for the entire deployment. With SPEEDLAN
routers, directional, sector, and omni antennas are easily intermixed enabling range optimization
and a more effective overall deployment density and lower deployment cost.
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| Antenna
choices - directional/sector/omni |
Wave Wireless mesh routers are typically sold without antennas enabling the System Integrator or
end customer to choose the best antennas for each router given the mesh topology and degree of
LOS/NLOS. SPEEDLAN routers can be used in combination to create mesh nodes of different
complexities, and unlike conventional mesh solutions, support the mixing of directional, sector, and
omni antennas. When two SPEEDLAN routers are combined at a mesh node, different antenna types
can be used for the uplink and downlink radios as needed for the specific application.
Range and interference are the big issues. While omni antennas receive RF signals from all
directions, they also receive RF interference from all directions which can reduce their effectiveness
in some environments. Also, for long range links, omni antennas send RF energy in directions where
there is no receiving radio. Directional and sector antennas are, by their nature, more focused and
better suited to long range links. Given equal radio transmit power and receive sensitivity, an LOS
(Line-Of-Sight) link with 17dBi sector antennas at each end will have a range that is 8x greater than
an identical link with 8dBi omni antennas at each end.
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| 4.9GHz
for security and video quality |
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In recent years, the
FCC has opened up 4.9GHz as a licensed band for Public Safety applications
in the US. Given the continual increase in 2.4GHz and 5.8GHz use in the US,
RF interference levels in most US cities are on the rise in these popular
unlicensed bands. By using 4.9GHz, Public Safety agencies can operate in a
relatively interference-free spectrum thereby improving available bandwidth
and lowering jitter - the result being higher quality video transmissions
with greater security. For anti-crime and counter-terrorism, video quality
is paramount and there will undoubtedly be a shift toward 4.9GHz for police,
fire, and other government wireless systems. The 4.9GHz spectrum provides a
50MHz band which can be divided into different numbers of channels according
to the needs of the application. SPEEDLAN routers for 4.9GHz support channel
widths of 5MHz, 10MHz, or 20MHz, providing up to ten non-overlapping
channels. Some SPEEDLAN versions are multi-frequency (tri-band), being field
configurable to support 2.4GHz, 5.8GHz, or 4.9GHz. This can enable a
transition from 5.8GHz to 4.9GHz without having to upgrade the router.
Public Safety customers can install a mesh on the unlicensed 5.8GHz band
while their 4.9GHz license is being processed, and easily convert later to
4.9GHz.
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| Certified
and proven |
All SPEEDLAN products are FCC certified including the new 4.9GHz version of the 9200 model. Some
versions supporting 2.4GHz are also available with ETSI certification for use in Europe and other
parts of the world. SPEEDLAN mesh routers have been successfully deployed in a number of video surveillance
applications including SuperBowl XXXIX in Jacksonville in 2005. The Jacksonville system covered
the stadium and many square miles of the surrounding area with more than 20 mesh routers.
Check the Case Studies section of our Website as more studies are published in the coming weeks.
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| Summary |
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Wave Wireless SPEEDLAN products are robust, flexible, and proven with
over 2,000 units deployed over the last two years. Our mesh routers are
reasonably priced, enabling customers to configure mesh topologies that
provide the high performance required for tomorrow’s video surveillance
applications. Wave Wireless, formerly P-COM, has been a quality supplier
to the wireless industry since 1992.
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More Information
|
Wave Wireless Speedlan 9200 Wireless
Mesh Router
The next generation of wireless mesh routers. The SPEEDLAN 9200 combines high performance, broad feature set, multiple operating frequencies, and hardware AES encryption to provide networking professionals the most flexible, scalable, and robust mesh routers. The SPEEDLAN 9200 system can cost-effectively expand your wireless coverage and overall productivity with ease.
|
Cisco Wireless Mesh Networking Solution for
Local Government
| The Cisco Wireless Mesh Networking Solution plays an important role in enabling
local governments and transportation agencies to enhance public safety and increase operational efficiency and service delivery.
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| Challenge |
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Local governments
share common challenges: to maintain a safe environment for their citizens,
increase service effectiveness, improve educational excellence, and drive
economic development. By adopting new business processes and the
technologies that make them possible, local governments are improving
citizen safety, increasing the quality of their services, fostering
educational excellence, and creating a business friendly environment. To
reach this, local government and transportation agencies face multiple
operational challenges that are brought on from budget and staffing
constraints, the desire to improve services to citizens, the mandate to
improve collaboration and communication within and among agencies and the
continuing need to enhance public safety. For example, first responders
typically operate independently but are now mandated to communicate and
share information with other government agencies. Improved collaboration and
communication between agencies such as police and fire ensure the best
possible outcome to emergency situations. To fulfill this mandate, many
agencies are opting to upgrade legacy systems such as Cellular Digital
Packet Data (CDPD) and 800-MHz wireless technology with next-generation
wireless networking equipment and applications. Legacy systems purchased
years ago have low-bandwidth that prevents integration with newer, advanced
applications such as video surveillance, traffic management control and
other IP-based applications. In addition, the legacy network lacks
frequencies, limiting the channel capacity for transmitting additional data.
With mounting pressure to increase revenues while reducing costs without
sacrificing service delivery, local government officials are formulating
strategies to:
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Enhance Public
Safety—Using IT networks to integrate existing applications with
new advanced applications, such as IP video surveillance and traffic
monitoring systems.
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Improve Public
Service Delivery—Increasing productivity and responsiveness of
agency employees. This can be achieved by automating administrative
tasks and by making information available to employees in the field,
thereby reducing the need for trips back to headquarters.
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Improve
Interagency Collaboration—Deploying network-oriented applications
to improve information exchange between municipal, state, local, federal
and transportation agencies
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Improve
Transportation Systems and Infrastructure—Upgrading
existing public transit and roadways with the latest intelligent
transportation system (ITS) to better manage internal operations and to
proactively prevent incidents by monitoring traffic and public safety in
potential trouble areas.
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Increase
Economic Development—Forming city and community partnerships with
neighborhood groups, schools, and small businesses to develop programs
and create opportunities to promote economic growth in the city.
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EXECUTIVE SUMMARY
Local government and
transportation agencies are often challenged to manage their operations more
efficiently, improve services to citizens, and enhance public safety with
limited resources. Government agencies implement technology to meet these
challenges but often times, the technology needed to improve operations is
costly and complex to maintain. The Cisco Wireless Mesh Networking Solution
offers innovative technologies such as zero-touch configuration,
self-healing, self optimization, and dynamic route capabilities that
simplify network deployment management and maintenance. This solution
enables new applications to accelerate communications and services, while
simplifying delivery of applications, lowering operational costs, and
improving government effectiveness and responsiveness. |
| Solution |
|
With the Cisco
Wireless Mesh Networking Solution, local government, public safety, and
transit agencies can extend their existing wired-network-oriented services
and applications beyond their building walls and across the city. This
provides innovative new ways to enable communications and service delivery
to agency employees and citizens in the community. The Cisco® Wireless Mesh
Network is a single, integrated, secure, and high-speed network which
enables government agencies to rapidly deploy new applications such as video
surveillance, traffic management and other IP-based applications. The mesh
network is ideally suited for metropolitan networks, being easy to install
on buildings and streetlight posts and is designed to scale to large outdoor
deployments. The Cisco Aironet® 1500 Series mesh access point can be
deployed with zero-touch configuration. Intelligent wireless routing, based
on the Adaptive Wireless Path Protocol creates a wireless mesh
infrastructure that dynamically optimizes the network routes and self heals
from interference or outages, while the Radio Resource Management (RRM)
software allows mesh access points to monitor their environments and adjust
channels and frequencies in real time to avoid interference from other
wireless devices. These automated capabilities help reduce deployment and
maintenance costs. The Cisco Aironet 1500 Series operates with Cisco
wireless LAN controllers and Cisco Wireless Control System (WCS) Software,
centralizing key functions of wireless LANs to provide scalable management,
security, and mobility that operates smoothly between indoor and outdoor
deployments. This solution provides agencies and individuals with access to
fixed and mobile applications to enhance public safety, efficiency,
productivity, and responsiveness (see Figure 1). |
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Figure 1. Wireless Mesh Network
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A properly designed
and configured wireless network provides the necessary safeguards for data
security and in-band radio interference. This is important for mobile users
that require secure remote access over wireless LANs to connect back to
their private data networks. Wireless technology enables flexible, mobile,
and dynamic communications. It provides ease of deployment, the ability to
deploy network devices where running fiber is cost-prohibitive, and the
ability to quickly and easily add networked devices.
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| Architecture |
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The Cisco Wireless
Mesh Network architecture (Figure 2) is based primarily on the Cisco Aironet
1500 Series, which operates with Cisco wireless LAN controllers and Cisco
WCS Software, centralizing key functions of wireless LANs to provide
scalable management, security, and mobility between indoor and outdoor
deployments. Designed to support zero-configuration deployments, the Cisco
Aironet 1500 Series easily and securely joins the mesh network, and is
available to manage and monitor the network through the controller and WCS
Software graphical or command-line interfaces (CLIs). Compatible with Wi-Fi
Protected Access 2 (WPA2) and employing hardware-based Advanced Encryption
Standard (AES) encryption between wireless nodes, the Cisco Aironet 1500
Series provides end-to-end security. |
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Figure 2. Wireless Mesh Network Architecture |
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Cisco Aironet
1500 Series Outdoor Wireless Mesh Access Point—With dual-band
simultaneous support for IEEE 802.11a and 802.11b/g standards, Cisco
Aironet 1500 Series outdoor wireless mesh access points employ the
Adaptive Wireless Path Protocol to form a dynamic wireless mesh network
between remote access points, and deliver secure wireless access to any
Wi-Fi-compliant client.
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Cisco Wireless
LAN Controller—The Cisco Wireless LAN Controller supports an
innovative architecture for large-scale wireless LANs by considering
individual access points as part of a larger system, and centralizing
certain functions of the 802.11 protocol. Based on the Lightweight
Access Point Protocol (LWAPP) and operating as part of this
architecture, the Cisco Aironet 1500 Series derives system-level
management of device configuration, security policies, and RF parameters
while providing Layer 2 or Layer 3 mobility.
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Cisco Wireless
Control System—The Cisco Wireless Control System provides a
powerful foundation that allows IT managers to design, control, and
monitor outdoor wireless networks from a centralized location,
simplifying operations and reducing total cost of ownership. The
following solutions, used by different agencies, are based on the Cisco
Wireless Mesh Network foundation.
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| Public
Safety Solution |
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Police, fire, and
emergency medical services agencies are using wireless technologies to
enhance safety throughout the community by improving the management of
resources and the quality and flow of information. Some of the applications
supported are:
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IP Video
Surveillance—Allows agencies to better manage and monitor many
locations throughout a city. With IP surveillance cameras installed on
lamp-posts, buildings, and in patrol cars, police can use their PDAs and
laptops to wirelessly tap into any camera that is integrated into the
network. This allows the police to quickly gain access to time sensitive
information on mission-critical situations and provide immediate
responses in a timely manner.
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Community
Policing—Allows for secure broadband access to databases,
fingerprints, and photo images from anywhere in the community. Secure,
high-speed capabilities are necessary to upload and download field
reports and images that require fast data throughput.
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Communications
Interoperability—Provides a unified IP network infrastructure that
allows multiple agencies to communicate and collaborate with each other,
thereby improving the flow of information and ability for first
responders to respond to an emergency situation.
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Telemedicine—Allows
doctors and emergency room technicians to diagnose and monitor patient
conditions as they travel on the road to the hospital. With access
points deployed along streets and roadways, ambulances can be equipped
with mobile networks and video cameras to provide two-way video image
and voice communications between the ambulance and emergency medical
centers. This type of application is critical to improving the safety
and health of citizens in the community.
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| Field
Service Worker Solution |
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Local government
agencies are deploying the Cisco Wireless Mesh Networking Solution to
improve business operations efficiency and to provide better service
delivery to citizens. Having access to the government database in the field
saves time in retrieving business-critical data, allowing employees to be
more productive and improve services to the community.
Applications supported
include:
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Ubiquitous
Wireless Access—The ability to connect from anywhere in the
community to the government database is critical for agency employees.
This saves time and effort, improving employee productivity and service
delivery response. Government employees such as building inspectors
would be more productive in enforcing licensing and building permits in
the field with easy access to government database from anywhere in the
community.
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Data Collection—Many
services performed by government employees across the community involve
collecting data and filing reports. City inspectors, public works crews,
utility crews, social workers, and other government employees can now
carry laptops, PDAs, and other wireless handheld devices to capture
data. This improves the accuracy of information captured at an onsite
location, and reports that are immediately filed and sent to department
headquarters helps to avoid delays in service delivery.
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Information
Data Sharing—A standards-based IP network foundation provides a
common infrastructure, integrating intelligent information network
services and applications. This allows multiple agencies to have access
to and share the same business-critical information for better
decision-making.
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| Public
Transit Solution |
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Public transit
agencies are deploying ITS to better manage resources, improve security, and
streamline their operations. The Cisco Wireless Mesh Networking Solution
provides a network infrastructure that enables ITS applications to be
deployed, which in turn allows transit agencies to access real-time
information, manage operational resources, enhance security, and improve
service delivery to their passengers.
Applications supported
include:
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Intelligent
Stations—Enables integrated communications so that voice, video,
and data can be more easily shared and services can be more easily
performed for all stations, terminal operations, and passenger
information services. A wireless network can be deployed to support
ticketing and fare collection, information kiosks, video surveillance,
and public wireless LAN service.
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Intelligent
Track Side—Provides an intelligent corridor along the track side,
allowing trains to have constant high-speed connectivity along the track
to support applications enabled on both the vehicles and along the
railroad. The Cisco Wireless Mesh Networking Solution can be deployed to
support applications like video surveillance, computer-based train
control systems, and integrated communications systems along the
track.
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| Business
Benefits |
| All SPEEDLAN products are FCC certified including the new 4.9GHz version of the 9200 model. Some
versions supporting 2.4GHz are also available with ETSI certification for use in Europe and other
parts of the world. SPEEDLAN mesh routers have been successfully deployed in a number of video surveillance
applications including SuperBowl XXXIX in Jacksonville in 2005. The Jacksonville system covered
the stadium and many square miles of the surrounding area with more than 20 mesh routers.
Check the Case Studies section of our Website as more studies are published in the coming weeks. |
Wireless Solution for IP Video Surveillance
- Cost and time saving of large scale
installations
-Do not need to dig ground putting coax cables
-Realize quick installations
- Mobility
-Enable to access mobile devices over wireless
--Monitoring video images from mobile devices
such as PDA...etc
--IP cameras can be moved on vehicles time to
time
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| Case
Study 1: Scott Peterson Trial |
- The courthouse perimeter had to be
secured during the trial
-With the use of wireless connection, it took ONLY 3 days for
installation
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Case
Study 2: Transportation at City of Fresno |
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