Posts Tagged ‘Ethernet switches’

Customer Solution: Power over Ethernet (PoE) for Intersection Monitoring

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Power over Ethernet for Intersection Monitoring

Improving traffic flow is a growing priority for expanding cities and towns, and one of the most efficient ways to reduce accidents and heighten safety is the use of intersection monitoring through video recording.  Not only is the video used to determine ways to decrease traffic congestion – it can also be reviewed for accident footage, fault resolution, and to assure that traffic systems are working correctly.

Power over Ethernet Intersection MonitoringA large city in the state of Iowa is improving its intersection monitoring system.  A total of seventy intersections with approximately two hundred cameras are currently deployed around the city, constantly recording traffic activity.  Along with cameras, other equipment is installed at the intersections such as preemption devices, conflict monitors, battery backup devices and other various sensors.  Preemption systems detect emergency vehicles and adjust traffic signals to allow high-priority vehicles to drive safely through the intersections.  Additional sensor data is recorded at the intersections such as car counting, lane changing, and speed of traffic.


Comtrol and Axis Communications – Technology Partner Program

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We have announced our official partnership with Axis Communications through the Technology Partner Program (TPP), and look forward to working with Axis to continue to improve product compatibility, increase successful product integration and enhance end user experience!

“The Axis Technology Partner Program is designed to bring to market the ‘best of class’ solutions for channel partners and their customers,” says Vince Ricco, Business Development Manager, TPP, Axis Communications, Inc. “We are excited to formally welcome Comtrol to the program and look forward to collaborating with such an interesting partner to offer true problem solving technology solutions that go beyond common capabilities.”

Technology Partner Program

Industrial Surveillance Partner Solution Note

“Our customers have come to expect the very best in reliable networking solutions for the past thirty years,” says Bradford Beale, President of Comtrol, “We are pleased to be involved in Axis’ Technology Partner Program.  Our ruggedized line of RocketLinx® Power over Ethernet switches has proven to complement the physical security solutions that Axis and its partners provide in North America, South America and Europe.”


For more Comtrol product information please visit


Total Power Control with Comtrol RocketLinx® Power over Ethernet Switches

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PoE Devices

– Joe House

As the number of network connected devices continues to increase exponentially, an uninterruptible network continues to get more valuable.  Without power, you have no network – without a network you may as well have no devices!

While there are many methods a system can employ to create redundancy, the base of redundancy often relies on three letters, UPS (Uninterruptible Power Supply).  Regardless of the electrical chaos that may occur in every area around a system, the battery backup UPS maintains power to the parts of the system that need it most.  If you plan to keep a series of PoE devices alive on a UPS, Comtrol’s RocketLinx switches have two key features that can help keep your UPS running like the Energizer Bunny®.

PoE Device

Before we get started: Where are the DC Power inputs on Comtrol’s Power over Ethernet switches?  Most of Comtrol’s PoE switches support redundant DC power inputs (accepting various input voltages depending on model, but shown with +48VDC here) via screw terminal connectors as shown below.  Taking some artistic liberties, you can see how two power supplies could be wired up!


SERIES: Power over Ethernet Features – Part III

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Rebooting non-PoE devices using Comtrol’s RocketLinx® switches

Have you ever wanted the ability to cycle the power to an IP camera (or any other device) remotely but couldn’t? … Either because it is not a PoE powered device in the first place, or because it is a PoE++ camera that consumes 60+ watts of power and has its own custom power injector?

If that is the case, you may find this little trick of great interest for your next camera deployment where you may need to hang one of those monster PoE++ cameras on a pole in a remote location, or work on a city-wide surveillance project – and getting someone up on a ladder to manually cycle the power is no small feat.

Here is how the trick works. 

First, select any of Comtrol’s managed RocketLinx Ethernet switches.  All of them have a relay that can be controlled via the online web interface.  The relays on our switches are normally open and rated for a max of 24VDC @1amp so you will also need an industrial-grade relay in this setup as well.

In this example, we are using this Potter & Brumfield relay with our switch that will accept a 24VDC coil voltage and will allow up to 10A 240VAC to be pumped through the contact.  A relay socket can be plugged into the relay which makes it easier to make the connections.

Here is the general diagram for making the necessary connections.


Once everything is wired, log into the web interface of the switch, open the warning folder and select the fault relay file.  It will open to this screen.


Ethernet Over Fiber-Optics: As clear as glass!

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Ethernet Over Fiber-Optics

As the demand for Ethernet connectivity increases in the market, so do the demands on Ethernet connectivity.  By transmitting Ethernet signals over fiber-optic cabling, users are able to extend the distance Ethernet signals will reach, protect against external Electro-Magnetic Interference (eliminating internal), and shield products from electrical surges.  All in all – by transmitting your data through light in a glass cable, fiber-optic connectivity is a great way to get more out of your Ethernet connections!

While the sales pitch on fiber above certainly sounds appealing, there are many aspects to consider during a migration to fiber-optic connectivity.  In order to select the best fiber optic connectivity solution, we must address:

1. Type of fiber-optic communication
2. Bandwidth
3. Fiber-optic connection type

Relating directly to these concerns, users must ask themselves

1. Type of fiber-optic communication

How do I want my data to be sent over fiber?

fiber-optic communication Fiber-optic communication is available in two different forms: Single-Mode and Multi-Mode.  Single-Mode, generally associated with longer distance capabilities, provides a hyper-efficient mode of transportation for the data-carrying light signals.  Multi-Mode fiber, while less expensive, is a less efficient method of fiber transmission.  As data travels across Single-Mode fiber it will degrade less than it would over the same distance with Multi-Mode fiber.

Furthermore, each fiber strand is designed to support a specific wavelength of fiber transmission.  Wavelength, measuring the distance between successive crests of a light wave, also influences efficiency and distance fiber can be transmitted.


SERIES: Linux Support at Comtrol – Part III

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Leveraging older PC hardware to perform daily tasks using Linux and Comtrol hardware

All too often, older PC hardware is thrown out merely because of it being unable to keep up with commercial operating system(s). Comtrol products, used together with the Linux operating system and older PC hardware you may have been considering throwing away, can be leveraged to perform daily tasks without the expense of a new PC being purchased.  This relates not just to Linux and it’s inherent ability to function well on older PCs, but also specifically to the Comtrol’s RocketPort® and DeviceMaster® hardware itself, and the design put into it.

– Nick Thompson

The Linux kernel is written in a manner wherein it can be compiled to squeeze every bit of performance out of the PC it’s running on.  When used with a Comtrol RocketPort or Comtrol DeviceMaster, the older PC runs as fast as it can for two reasons. The Linux kernel is compiled to squeeze performance, and the RocketPort and/or DeviceMaster are smart devices – they do not force the PC to put forth any of its computing power to run the devices, unlike ‘dumb’ multi-port serial boards which are essentially standard serial ports slapped onto a PCI board.  These take resources to run, and let’s remember we’re working with an older system here.  We can’t afford to use those resources, or the PC may be too slow to perform the task it has been selected for.

Pre-build vs. Compiling your own: Kernel issues to be considered on older machines  
One very nice thing these days within the Linux community is the fact that you can now download distributions which are designed from the get-go for older machines.  They will save you the trouble of installing a standard Ubuntu, Fedora, Suse, etc. and having to then re-compile your own kernel.  This obstacle is the biggest in squeezing every bit of performance out of older machines. (Again, the RocketPort – because of its ASIC processor – and the DeviceMaster itself take the load of the standard serial ports that a ‘dumb board’ would put onto the machine, and offload that onto the Comtrol RocketPort or DeviceMaster. This saves CPU cycles and RAM for the operating system and the task at hand.) There are many distributions out there at the moment that do this.  One I would recommend is Puppy Linux, though again there are many and much like with standard Linux distributions.  You’ll want to select one that uses the package management system you are used to, that has the features you want/need when planning an installation on an older PC with Comtrol products.  You can find links to various resources related to such things as Linux distributions that are good for this purpose at the end of this post.

Linux Comtrol RocketPort DeviceMaster  Untitled-1Linux Comtrol RocketPort DeviceMaster

Don’t throw away that Pentium II just yet! 
This post is not theoretical. I speak with customers who are using a Pentium II 450 megahertz system (or similar) to accomplish tasks that others use a brand new $600-$1000 PC for.  The reason they are able to accomplish this is offloading of load to the Comtrol products, as well as the fact they’ve chosen to use a Linux distribution aimed at just such a thing: to accomplish a task, and accomplish it well.  Not attempt to install a fully functioning desktop PC, but to accomplish a task.  Comtrol products, together with Linux, will allow you to do just such a thing, and with no PC budget to speak of – disregarding that old Pentium II you keep meaning to throw away.

For more information >> Comtrol’s DeviceMaster device servers, RocketPort multi-port serial cards and RocketLinx® industrial Ethernet switches

Linux Distribution Links Updates on new versions of distributions, etc.

Puppy Linux Older PC Linux Distribution

If you have any questions whatsoever regarding Linux support, please contact Nick Thompson with Technical Support at [email protected] or (763) 957.6138.

Transportation & Bus Surveillance: Mobile Security

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As public transportation is becoming more popular in North America, following successful models used in foreign transportation systems can help guide our decisions and processes concerning public safety initiatives.

Adding surveillance to improve the safety of public transportation is one such example.  A European bus company was looking for an industrial Power over Ethernet (PoE) switch to connect critical components of its mobile security system.  Installations on the bus included six security cameras, a network video recorded (NVR) and a Wi-Fi router, that all required communication and power.  Devices used in transportation surveillance systems such as on buses or trains have a unique set of requirements and specifications that are crucial to operability and efficiency.  Devices must be compact and rugged to maximize available space, reduce crowding and survive extreme temperature conditions and harsh environments.

power over ethernet mobile security RocketLinx voltage boost

Comtrol’s RocketLinx® ES7110-VB (voltage boost) switch is used in this security configuration to ensure quality system performance and to meet the system specifications. As cameras send data and video to the NVR, it is transferred wirelessly from the bus to a remote monitoring room via the Wi-Fi router.  The RocketLinx ES7110-VB has eight 10/100BASE-TX PoE injector ports for directly powering remote equipment and reducing wiring and installation costs, and two Gigabit uplink ports for megapixel video transmission and high-quality streaming data and video.  Additionally, the switch provides a 12/24VDC power input boost to 48VDC, eliminating the need for a separate power supply or voltage converter to conserve space and cost.

Featuring a DIN rail mount and measuring less than two inches in width, the ES7110-VB works well with limited space and other equipment placement in a surveillance system.  Dual redundant power independent power inputs for potential power loss enables a backup power supply to compensate for loss of main power and maintain camera operation.  The rugged IP30 enclosure protects the switch from vibration and shock, while the -25° to +60°C operating temperature allows for installation in a variety of environments.

Comtrol’s RocketLinx Power over Ethernet switches are engineered for industrial applications such as IP video surveillance or wireless broadband, where the power source is not conveniently located.  With rugged, drip-proof housings, redundant power inputs and performance command-line interfaces, these PoE switches provide reliable networking solutions.

With both managed and unmanaged models available, the RocketLinx ES series of switches provide cost-effective networking solutions delivering the industry’s best rugged Ethernet switch technologies.

Download PDF here >>


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