Managed Ethernet Switches

Key Features For a Powerful Industrial Network 

Success for an industrial engineer has always had roots in the search for dependability and function at an affordable cost.

Ethernet always held out the promise of high function in most regards, but determinism was missing. Hardware that could survive industrial settings was also lacking. The technology, hardware, software and volume that have made Industrial Ethernet affordable and useful is a relatively recent development.

Industrial managed ethernet switches are the key to this improvement. Until a few years ago, the typical Ethernet installation used repeaters to distribute data. The resulting network resembled this:

Managed Ethernet Switches

 

Ethernet resolves collisions by randomly delaying data. Therefore, this configuration doesn’t work for complex networks with high data rates and time-sensitive applications. While good for non-industrial uses, Ethernet was at first unsuitable for industrial control applications. Replacing repeaters with switches made for a more reliable network:

Managed Ethernet Switches

 

Though this was effective, it was years before it was practical in industrial settings. Switches were costly, and they were reserved for special applications. There was the problem of the right equipment for industrial settings. Non-industrial strength switches required special enclosures, mounting, shelves and power supplies that weren’t always possible. Vibration, heat and other hazards were also problems.

Because industrial duty Ethernet switches are now affordable and available, these limitations are resolved. As a result, industrial Ethernet networks are becoming standard for many installations.

TAKING WHAT INDUSTRY DISHES OUT: INDUSTRIAL SWITCH HARDWARE

Ethernet switches made for industrial situations don’t get the pampering that office equipment does, so they’re built two or three times as strong. Some of the specifications for standing up to industrial environments include:

  • Temperatures typical of industrial settings. These range from-40º to 70ºC (-40°F to 158°F).
  • Protection ratings of IP30 and up to protect the equipment from industrial debris.
  • 12 to 48 VDC Redundant Power Inputs are available on many models, to ensure stability.
  • DIN Rail and Panel Mount cases are used to avoid the hassle of adding special shelving and strapping down commercial equipment.
  • When an office network goes down, people complain. Machines don’t, so many industrial managed switches feature an alarm relay and email alerts to notify the network administrator in the event of a network malfunction.
  • Mean Time Between Failures (MBTF) is usually enhanced for industrial Ethernet switches – to 300,000 hours (34 years!) is not unusual – so material failures are rare events.

THE “INTELLIGENCE” OF MANAGED SWITCHES

Managed switches are also called intelligent switches. This means they use software to analyze and improve network performance. Here are some of the benefits:

Virtual Local Area Networks
Managed switches may be programmed to distribute data to Virtual Local Area Networks, or VLANs. VLANS are subgroups of data interfaces, created by programming instead of wired connections.

There are two basic types of VLANs. With an IEEE 802.1Q VLAN, the switch inserts a VLAN header in each information packet, to identify VLAN recipients:

Managed Ethernet Switches

 

With a Tag VLAN, the VLAN is assigned to a specific port. All users of the port must be members of the same VLAN.

VLANs simplify network management. A single connection can be used to manage multiple VLANs – physical location is irrelevant. Accidental crossover of data from one VLAN to another is simply not possible. Plus, reconfiguring a VLAN is an easy software solution, versus changing wired connections on a regular LAN.

Redundancy
Redundancy, where mission-critical components and functions are duplicated, is the surest path to system reliability. But full redundancy may be difficult to justify except in critical applications (a nuclear power plant or process involving large quantities of high hazard chemicals would certainly qualify as critical).

A practical solution that provides a high degree of redundancy is redundant ring technology using managed Ethernet switches. One leg of the ring is disabled until a fault develops elsewhere in the ring. When that happens, the disabled leg (backup path) is enabled and communication proceeds.

Managed Ethernet Switches

For link failure, the redundant ring group is self-healing, and recovery proceeds without human intervention. If a ring group switch fails, only the devices attached to that switch would be cut off from the network.

The original redundant ring technology, Spanning Tree Protocol or STP, allowed ring recovery times of 30 seconds, too slow for many industrial applications. With Rapid STP (RSTP), recovery times dropped to 3 seconds, still not fast enough for some processes. Many switches now use proprietary technology for recovery in 300 milliseconds or less, fast enough for demanding applications.

Port Mirroring
Port mirroring is another advanced feature of intelligent switches. It sends data from one switch port (even the data for an entire VLAN if it’s on one port) to be sent to a monitoring port at another switch. It’s used for detecting intrusions or network diagnostics.

IGMP
Internet Group Management Protocol or IGMP capability allows a switch to “listen in” (commonly called IGMP Snooping) on network multicasts. The switch then delivers traffic to ports where the attached device signals it’s available to listen to the broadcast.

Managed Ethernet Switches

This saves downstream devices from dealing with unneeded traffic.

Simplified Network Management Protocol
An administrator uses Simplified Network Management Protocol, or SNMP, to monitor and configure PC’s, switches and other devices. This is important as the number of devices increases, to record and analyze network traffic, notify the network manager of network problems in real time and to speed and simplify corrections.

Web Based Management
An advantage of Ethernet based devices, tools or programs is web access to manage network operations, configuration and security. Managed switches have this capability, and efficiency and stability are facilitated by remote web access.

SECURITY

The “silver bullet” of security is for only necessary communication to flow through a network, when it’s needed and only with devices that need it. Managed switches are an important part of the solution, as they create and manage VLANs, monitor problem traffic through port mirroring, and enable other security related measures.

For example, switches with Media Access Control (MAC) ID filtering, port locking and password protection help prevent tampering and trespassing on the network. Also, if a network is overloaded from device or operating errors, rate limiting or VLANs created by managed switches can limit or isolate the problem.

Flexibility and Future Expansion
Network change and expansion is easier with industrial managed switches. Adding or reconfiguring a collision domain or VLAN is a simple when done through the control interface. Changes made with fewer errors in less time certainly meet the industrial engineer’s prime directive of “do it better, do it cheaper, do it faster.”

CONCLUSION

Current prices per port make the decision to use an industrial switch easy. As for choosing between managed and unmanaged switches, it’s a simple calculation. The more complex or likely a network will grow in the future, the more managed switches are needed.

The momentum of Ethernet technology and its successful application in industrial settings suggests that adoption at the highest affordable level of function is a necessity.

Ethernet can transmit data from a variety of older technologies, and has effectively extended the life of these technologies into the foreseeable future. It’s also leading edge in its potential for speed and applications. History suggests Ethernet will long be the standard, meeting the demands of new technologies. Managed switches will continue to be the essential components of advanced networks.

B+B SmartWorx offers a full line of managed and unmanaged Industrial Ethernet Switches.

Making Wireless Sensors as Accessible as Web Servers

The Internet of Things revolution is upon us, and by the year 2020, therewill be over 50 billion connected things in the world. With the world’s population increasing and resources...

Wzzard Network Planning and Installation Application Note

Planning, deploying and installing a Wzzard network does not require any special network expertise. But some simple guidelines should be followed. Let’s discuss some topics that are the keys to enabling a robust network installation. These include Planning a Deployment, Verification of Network Health and Troubleshooting common problems.

Getting Security Right in Wireless Sensor Networks

You may define rules in the router for switching between two APNs on one SIM card or between two SIM cards or network providers. The router can automatically switch between the network setups when the active PPP connection is lost, the data limit is exceeded, or the binary input on the front panel goes active.

Wzzard Security Platform

The Spectre Network Gateway places the SmartMesh IP network behind a firewall. If connecting via the cellular data networks, the Spectre Network Gateway lets users use VPN tunneling, which makes the cellular systems as secure as proprietary infrastructure.

A Second Warm Welcome to Wireless Mesh Networking

You may define rules in the router for switching between two APNs on one SIM card or between two SIM cards or network providers. The router can automatically switch between the network setups when the active PPP connection is lost, the data limit is exceeded, or the binary input on the front panel goes active.

Connect Any Sensor to the Internet of Things

You may define rules in the router for switching between two APNs on one SIM card or between two SIM cards or network providers. The router can automatically switch between the network setups when the active PPP connection is lost, the data limit is exceeded, or the binary input on the front panel goes active.

Spectre Router Configuration for Automatic Failover

You may define rules in the router for switching between two APNs on one SIM card or between two SIM cards or network providers. The router can automatically switch between the network setups when the active PPP connection is lost, the data limit is exceeded, or the binary input on the front panel goes active.

Sensor Networking Cost Model

Are the high costs of deploying cabling in your industrial environment preventing you from deploying a remote sensor monitoring solution?

Cellular and the Promise of SWARM Intelligence

The power of SWARM intelligence is visible in nature, where the collective efforts of very simple creatures like ants, bees and termites can produce highly sophisticated results.

SWARM Intelligence: Greater than the Sum of Its Parts

The power of SWARM intelligence is visible in nature, where the collective efforts of very simple creatures like ants, bees and termites can produce highly sophisticated results. Termites build enormous...

The Basics of MQTT

Message Queue Telemetry Transport (MQTT), is an open, lightweight publish/subscribe messaging protocol that was developed specifically for small, constrained devices over wireless networks. MQTT brings a simplicity and scalability not...

Solving Industrial Monitoring Challenges through Wireless I/O

Abstract Remote monitoring and control applications present a range of challenges. In recent years, new technologies and products have emerged to address some of these challenges, but in many cases...

SimpleWire Replacement with Zlinx® Radio Modems: Knowledge, Tips, Fixes

A problem free wireless network installation is more than a wish, it’s what most of our customers experience. But a little knowledge and planning up front makes succeeding on your...

Wireless Technology for Modern Health Care

Some medical devices become immensely more valuable if you can make them mobile. Moving a modern medical cart from room to room is far more efficient than moving the patients...

Smart Phones & M2M – Connecting Made Easy, Finally

by Bill Conley You could argue that wireless data communications began in 1782, when Claude Chappe used semaphore towers to send messages between Paris, France, and the city of Lille,...

USB: Adaptable for Industrial Applications

The Universal Serial Bus (USB) provides a high data rate and Hot Swap connection for PCs, providing an easy connection to a wide variety of multimedia and network USB devices....

Ruggedizing USB Connections for Tough Environments

USB is ubiquitous, it’s useful and it’s here to stay. But it isn’t inherently rugged or reliable. It’s up to you to make it that way. When technician John Baker...

The Ten Commandments of USB

Don’t forget that USB uses copper wire and can thus transfer power surges from lightning strikes or heavy machinery to places where they can do serious damage. You can prevent...

Data Line Isolation Theory

When it comes time to protect data lines from electrical transients, surge suppression is often the first thing that leaps to mind. The concept of surge suppression is intuitive and...

Optical Isolation: Your Best Investment for Reliability

In 1999 the Science department at NASA conducted a study on lightning, ground voltage, and structural impact. A building in North Carolina, located within 45 meters of a 42-meter water...

Make Your Tablets and Smart Phones Smarter – Add Serial Capability for Seriously Remote Data

by Andy Ross, Director or Wireless Applications To paraphrase Mark Twain, rumors about the demise of serial ports are greatly exaggerated. Serial ports are everywhere, in everything from industrial automation...

RS-485 Connections FAQ

How Do I Make RS-485 Connections? First check the pinout connections and specifications of the devices you want to connect in order to determine whether you need a “2-wire” RS-485...

RS-422 and RS-485 Applications eBook

A Practical Guide to Using RS-422 and RS-485 Serial Interfaces The purpose of this ebook is to describe the main elements of RS-422 and RS-485 data communications systems. The authors...

MTBF, MTTR, MTTF, FIT – Explanation of Terms

The intent of this White Paper is to provide an understanding of MTBF and other product reliability methods. Understanding the methods for the lifecycle prediction for a product enables the...

An Overview of Fiber Optic Technology

The use of fiber optics in telecommunications and wide area networking has been common for many years, but more recently fiber optics have become increasingly prevalent in industrial data communications...

Calculating Fiber Loss in Fiber Optic Networking

Fiber optic networking can be a daunting undertaking, but it really is not as difficult as it seems. Understanding factors such as fiber modes, fiber launch power, receive sensitivity, fiber...

Troubleshooting and Auto-Negotiation Features for Media Conversion Products

Media converters make the critical connection between different types of media, ensuring seamless integration of new equipmentin legacy networks. Media converters simply provide the electrical-to-optical conversion, and cost-effectively bridge the...

Introduction to Modbus

Modbus is one of the most popular protocols used in the industrial world. Supporting traditional serial protocols of RS232/422/485 and Ethernet protocols allow industrial devices such a PLCs, HMIs and...

Media Converters

Introduction to Media Converters Media converters play an important role in today’s multi-protocol, mixed media Local Area Networks. For example, LAN administrators can deploy media converters to integrate fiber optic cabling and active...

Port Powered Serial Converters FAQ

How do port powered serial converters derive their power? These converters steal their power from the connected RS-232 device’s output signals. As an example, a PC normally has outputs on the...

Cellular Data Networking Goes Industrial

Refresh cycles for industrial data communications equipment have traditionally been measured in decades rather than years. That’s partly because of the enormous capital investments involved, partly because so many industrial...

What is SmartMesh IP™?

SmartMesh IP is defining the way to connect smart devices. With advanced network management and comprehensive security features, SmartMesh IP delivers reliable, scalable, energy efficient wireless sensor connectivity. Using up...

What Is The Internet of Things?

There’s a lot of hype surrounding the phrase “Internet of Things”, but what does it really mean for you? Mike Fahrion offers a pragmatic approach to realizing the potential for...