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NMS Overview: Central managers, RTUs, and NMTs

By Andrew Erickson

September 26, 2023


Network management, at the most basic level, helps you keep a watchful eye on your local and distant facilities and their equipment.

I find it's best to learn broad concepts like Network Management Systems (NMS) by reviewing specific examples from real-world projects. That's why I've pulled an RFP (Request for Proposal) from 2020 titled "Station Alerting". This comes from a county in Texas, specifically the Police/Fire/EMS 911 authority.

This RFP highlights the essential requirements for a Network Management System (NMS). This will help you lay the groundwork for understanding remote monitoring, Remote Terminal Units (RTUs), and central master stations.

Remote Monitoring & RTUs: The front lines of your NMS

Section 7 of the RFP requires a system capable of smoothly gathering, processing, and displaying information from various vital systems.

The document states:

"The system shall acquire, process, and display information in an integrated and uniform fashion for a variety of critical systems."

This is a crucial overview of network management generally. Any decent NMS allows you to keep tabs on different aspects of your network, from radio system interfaces to power systems and data networks, ensuring nothing slips through the cracks.

In this architecture, RTUs are your "eyes and ears". They are deployed at your various remote sites to collect and send mission-critical data back to you.

As one specific example that I obviously know a lot about, DPS Telecom's NetGuardian RTUs are an excellent point of reference. They happen to align well with this RFP's requirements.

NetGuardians can support from as few as 2 to as many as 256 status alarm points. They also have at least eight control outputs and eight analog inputs, both expandable.

Your RTUs must integrate with your central master station

When planning your project, remember that your chosen RTUs should not only be effective in collecting data - but should also integrate seamlessly with your central units (more on that later in this article). Both components need to work hand in hand, seamlessly interacting to create a solid, reliable network monitoring system for your project.

This integration is essential for enhancing the functionality and efficiency of your overall system.

As stated in the RFP:

"RTUs shall be fully compatible with NMTs supplied and provide complementary functionality wherever necessary to provide a complete working system."

Imagine the RTUs and NMTs as partners working together: the RTUs collect and send important data, while the NMTs process and display this data. For you, this partnership should be smooth, with each component understanding and complementing the other's role.

Continuing our use of a DPS example, NetGuardian RTUs offer a reliable data collection and transmission platform. A robust polled protocol is used with a T/Mon central manager. This offers several advantages over SNMP.

Still, the popularity of SNMP is so great that we decided long ago to add SNMP (and eventually SNMPv3) to all NetGuardians. Some less common builds also support standards like DNP/DNP3.

We built our devices in this way precisely because any RTU is pointless if it can't effectively talk to your central NMS system. Aside from small numbers of RTUs with a built-in web interface, you need compatibility with your central alarm aggregator.

Central Master Stations

Next, let's look at central master stations, also known as Network Management Terminals (NMTs). These larger devices serve as the control centers for your Network Management System (NMS). Their role is both pivotal and indispensable for the seamless operation of your entire network.

According to the RFP document, NMTs bear the responsibility of providing primary processing, display, and control of information that flows from the myriad of RTU locations scattered across your network.

The document specifies:

"NMTs shall provide primary processing, display, and control of information to and from a variety of RTU locations."

Central managers (NMTs) must present system status and alarm conditions instantly and accurately, ensuring you're continually updated regarding the operational status of your network.

For a real-world example, you could consider the T/Mon Central Master Stations offered by DPS Telecom.

T/Mon is designed not just for compatibility with a wide variety of RTUs but also to offer a unified platform where alarms can be viewed and acknowledged efficiently. This gives you a centralized hub for all network management tasks. That makes your job easier.

T/Mon servers have also been developed with an eye for your possible future needs. The flexible and expandable architecture of these units allows for easy updates to both software and hardware components. This is in line with the RFP's requirement for NMTs to feature expandable software and hardware architecture.

If you plan ahead, as your network grows and evolves, your central master stations can adapt and expand to meet your changing needs. You'll earn this benefit without undue stress or requiring a complete system overhaul too early in the device's life cycle.

Whether you buy a T/Mon or explore other alternatives like a general-purpose SNMP manager, you must ensure that your NMT is robust, reliable, and capable of seamless integration with good RTUs. With the right NMT at the helm, you'll be well-positioned not only to meet but exceed the expectations and requirements outlined in RFPs like this one. If you're writing an RFP rather than responding to one, now you have a general idea of what you should be demanding from interested suppliers.

You can propel your NMS project to be your next major success

Taking a step back and looking at the big picture presented by this 911 public-safety RFP, it's clear to see the crucial roles played by remote monitoring, RTUs, and NMTs in any functional Network Management System (NMS).

Each component, with its unique function, contributes to creating a system that not only meets your basic requirements but also offers you reliability and efficiency in monitoring and managing your network.

In this context, products like DPS Telecom's NetGuardian RTUs and T/Mon Central Master Stations are potential options that align well with the requirements and specifications in this and similar RFPs.

As you move forward in planning and eventually deploying your Network Management System, remember to weigh your options carefully, always keeping in mind the importance of compatibility and functionality between the RTUs and NMTs.

With careful planning and the right components, you'll be well on your way to implementing a network management system that is not only robust and reliable but also efficient and user-friendly, making your network monitoring and management tasks smoother and more manageable.

Give me a call to discuss NMS concepts and your project goals

I understand that this stuff isn't simple, particularly if you're working on your first NMS project. That's why I make myself (along with DPS Telecom's Engineering team) available to you to answer any questions you may have.

Give me a call. Just tell me what you're trying to accomplish. I'll help you plan your next steps:

Call 1-800-693-0351 or email sales@dpstele.com to get started now.

Andrew Erickson

Andrew Erickson

Andrew Erickson is an Application Engineer at DPS Telecom, a manufacturer of semi-custom remote alarm monitoring systems based in Fresno, California. Andrew brings more than 17 years of experience building site monitoring solutions, developing intuitive user interfaces and documentation, and opt...