How To Implement SNMP Monitoring In Your Network: A Practical, Step-by-Step Guide

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How much do you need to know about SNMP to implement SNMP alarm monitoring on your communications network?

You don't need to study SNMP on a theoretical level to make your implementation successful.
But there are some SNMP issues that are potential pitfalls, and you need to know how to avoid them.

This white paper is a step-by-step guide to SNMP alarm monitoring implementation, focusing on the practical problems that can arise and how to solve them.



















Why Should You Come to
DPS Telecom Factory Training?

Factory Training

DPS Telecom Factory Training is the fast way to learn everything you need to know about your T/Mon system and DPS remotes. If you work with DPS equipment, or train or manage those who do, you need DPS training.
This in-depth course will make you an expert T/Mon user in just four days, saving you weeks of trying to teach yourself with a manual. Plus you'll learn advanced T/Mon techniques - tips and tricks that will save you hours of work and make your monitoring much more effective.

Larry Hamilton

"This training is worth a lot more because it's taught by the people who actually work with the system, not some corporate trainer."
-Larry Hamilton, U.S. Telepacific






Personal Instruction in a Friendly Atmosphere

Anyone who's attended a DPS Factory Training Event will tell you it's not like any other training course. Here's the difference:

• Personal instruction in small classes: Classes are capped at nine people, so your instructor can focus on you. If you want to spend more time on a topic, your instructor or a DPS engineer will be happy to meet with you in a one-on-one breakout session.

• Learn from engineers with real-world experience: Your DPS instructors are skilled engineers who have worked on DPS product design and field implementations. They know your equipment and how you use it.

• Work hands-on with real-world equipment: At a DPS Factory Training Event, you'll work directly with the equipment - and you'll get the unique know-how that only comes with personal experience.

• Complete access to DPS Telecom: You'll talk to the engineers who designed your equipment, tour the factory where it's built, and see the latest DPS products. If you've got a suggestion on how we can improve our products or services, we'll listen to you - and act to meet your needs.

• Friendly, welcoming atmosphere: The entire DPS staff will make you feel welcome. Hosted lunches and dinners will give you a chance to casually unwind with your classmates. You'll be able to share telemetry tips and experiences, and you'll get to know people you can relate to. Come to Fresno a day or two early and you can explore the splendors of nearby Yosemite, Sequoia, and Kings Canyon National Parks


Introduction

You've just been put in charge of implementing SNMP alarm monitoring on your network. What do you really need to know about SNMP to make this transition work?

You could spend months studying protocol architecture or MIB structure, but that's not necessary to get a monitoring project off the ground.

You don't need to know SNMP on a theoretical level to make your SNMP deployment successful. SNMP telemetry is still telemetry, and most of what you already know still applies.

In fact, your telemetry experience is going to be highly valuable during your SNMP implementation. Even though it uses an IP protocol, SNMP equipment is not plug-and-play simple. You still have to deal with all the usual issues of a telemetry deployment, like data transport, interface compatibility, configuration, and debugging.

But there are also some SNMP-specific issues that you need to be aware of. These issues can potentially turn into pitfalls that can stop your SNMP implementation in its tracks, stretch your project over time and over budget, even reduce your overall visibility of your network.

This white paper will guide you, step-by-step, through each stage of a typical SNMP deployment. Along the way, we'll flag the problems you may run into and offer some suggestions for solving them.



Preliminary Planning: Assess Your Existing Network Before You Budget

Before you start any work on your deployment even budgeting you need to begin with a thorough assessment of your existing network, to determine how much of your existing transport and network equipment is compatible with SNMP monitoring.

You certainly want to identify any potential replacement issues before you budget, or you may be caught short by unexpected problems. But equally, you want to take advantage of opportunities to reduce your capital expenditures by continuing to use existing transport and equipment.

Network surveys can be complex. A software survey tool can help make sure you don't miss any essential network elements.

For some ideas on how to evaluate your network, see"DPS Telecom Remote Site Survey," on page 5.

Learn SNMP the Easy Way: Attend DPS Telecom Factory Training

Factory Training

"I had heard of SNMP, but I never knew what SNMP was until I learned it at DPS Factory Training. I'm not at all scared about SNMP now." - Derek Willis, Paul Bunyan Telephone

Learn SNMP-based alarm monitoring in-depth in a totally practical hands-on class. The DPS Telecom Factory Training Event will show you how to make your alarm monitoring easier and more effective. You'll learn SNMP alarm monitoring, ASCII alarm processing, Derived Alarms and Controls, and how to configure automatic email and pager notifications. DPS training is the easiest way to learn alarm monitoring, taught by technicians who have installed hundreds of successful alarm monitoring deployments.


For dates and registration information, call 1-800-693-3314 today or go to www.dpstelecom.com/training.



Step One: Survey Your Existing Data Transport

The top challenge in your SNMP implementation is making sure that you have enough bandwidth for SNMP traffic going to all your remote sites.

So the first step in your network assessment is to examine your present telemetry network map. You need to identify the existing transport that's currently in place and determine if any adjustments need to be made for SNMP monitoring.

Your goal here is to collect the information you need to create a new network drawing that represents the transport you'll need to deploy in order to support SNMP monitoring. This new map will be your guide to planning your transport upgrades.

The ideal transport for SNMP data is LAN - but in most cases, your LAN is not going to extend to all your remote sites.

If no LAN connection is available, you do have other options. You can also send SNMP data over an order wire, a radio overhead channel, a channel bank, or PPP over a dial-up or direct link.

The key question for all of these alternative transports is this: Do they provide sufficient bandwidth? UDP packets are small, and most SNMP traps are small, so you don't need a huge amount of bandwidth, but there has to be enough for your probable amount of network traffic.

Insufficient bandwidth is going to increase latency and reduce response time. Medium-bandwidth transport might be OK, but smaller bandwidths are going to be clearly inappropriate for mission-critical network alarm monitoring.

You should be very careful about using lower-bandwidth transports like 202 channels or serial links. These connections should be analyzed for their speed and capacity before being certified for SNMP traffic.

You should also watch out for communications links that involve multiple conversions from one type of transport to another. These will also increase the latency of your SNMP monitoring.

At any site where the currently available data transport is less than optimum, you're going to have to consider upgrading to a higher-bandwidth connection.

By the time you have completed your transport survey, you can divide your sites and their existing communication links into four categories:

  1. Sites that have transport that is already adequate for SNMP traffic.
  2. Sites whose data traffic can be re-routed from low-bandwidth transport to high-bandwidth transport.
  3. Sites that can be economically upgraded to bandwidth adequate for SNMP traffic.
  4. Sites that cannot be easily or cheaply upgraded to high-bandwidth or LAN traffic. (This is a serious potential pitfall; please see "High Costs of Migrating Remote Sites to LAN,")

Using this information, you can now redraw your telemetry network map to represent how your transport network needs to look for SNMP monitoring. This updated map will be your guide to systematically and efficiently upgrading your transport network.


Step One: Survey Your Existing Data Transport

The top challenge in your SNMP implementation is making sure that you have enough bandwidth for SNMP traffic going to all your remote sites.

So the first step in your network assessment is to examine your present telemetry network map. You need to identify the existing transport that's currently in place and determine if any adjustments need to be made for SNMP monitoring.

Your goal here is to collect the information you need to create a new network drawing that represents the transport you'll need to deploy in order to support SNMP monitoring. This new map will be your guide to planning your transport upgrades.

The ideal transport for SNMP data is LAN - but in most cases, your LAN is not going to extend to all your remote sites.

If no LAN connection is available, you do have other options. You can also send SNMP data over an order wire, a radio overhead channel, a channel bank, or PPP over a dial-up or direct link.

The key question for all of these alternative transports is this: Do they provide sufficient bandwidth? UDP packets are small, and most SNMP traps are small, so you don't need a huge amount of bandwidth, but there has to be enough for your probable amount of network traffic.

Insufficient bandwidth is going to increase latency and reduce response time. Medium-bandwidth transport might be OK, but smaller bandwidths are going to be clearly inappropriate for mission-critical network alarm monitoring.

You should be very careful about using lower-bandwidth transports like 202 channels or serial links. These connections should be analyzed for their speed and capacity before being certified for SNMP traffic.

You should also watch out for communications links that involve multiple conversions from one type of transport to another. These will also increase the latency of your SNMP monitoring.

At any site where the currently available data transport is less than optimum, you're going to have to consider upgrading to a higher-bandwidth connection.

By the time you have completed your transport survey, you can divide your sites and their existing communication links into four categories:

  1. Sites that have transport that is already adequate for SNMP traffic.
  2. Sites whose data traffic can be re-routed from low-bandwidth transport to high-bandwidth transport.
  3. Sites that can be economically upgraded to bandwidth adequate for SNMP traffic.
  4. Sites that cannot be easily or cheaply upgraded to high-bandwidth or LAN traffic. (This is a serious potential pitfall; please see "High Costs of Migrating Remote Sites to LAN,")

Using this information, you can now redraw your telemetry network map to represent how your transport network needs to look for SNMP monitoring. This updated map will be your guide to systematically and efficiently upgrading your transport network.


RTU Capacity and Function

1. How many remote sites do you need to monitor?

2. Do you want video surveillance at those sites?

3. Do you want a building access control system to manage entry to those sites?

4. How many alarm points do you need to monitor at each site?

5. How much growth, in sites and alarms at each site, do you anticipate over the next 5 years?

6. Do you need any analog inputs (e.g., voltage, temperature, humidity, signal strength)?

7. How many ASCII device (e.g., switches, routers, etc.) will you monitor at your remote sites?

Installation

1. How do you currently connect to your remote sites? (LAN, overhead, digital or analog circuit, terminal server, microwave?)

2. Do any of your sites support an alternate path communications link?

3. What type of power do you have at the master and remote sites? (-48 VDC, 110 VAC, other?)

4. How do you want to mount your RTUs? (23" rack, 19" rack, wall, tabletop?)

5. Who will install your RTUs?

This is just a small sample of the DPS Telecom Remote Site Survey. The full Remote Site Survey is a complete 5-page guide to evaluating your network alarm monitoring needs. For your copy of the Remote Site Survey, call DPS Telecom at 1-800-693-0351



How You Can Migrate to LAN Without Killing Your Budget

Installing LAN connections at remote sites is a significant cost-it can be the single biggest expense of your SNMP implementation. Many remote sites are distant and isolated, making them difficult to be integrated into your corporate network.

Fortunately, you don't need a LAN connection at every remote site. SNMP data can also travel over an alternative transport, like PPP over a dial-up connection or dedicated line. The answer is controlled migration to LAN transport.

How LAN Migration Works

Install SNMP RTU

Step One: Install an SNMP RTU with Dial-Up or Dedicated Line Capability
In a controlled LAN migration strategy, you first integrate your remote sites into your SNMP-based monitoring system, using existing transport.

To do this, all you need is an SNMP-based remote telemetry unit (RTU) or proxy device that supports both LAN transport and your existing transport.

In this diagram, a site that is originally monitored by a legacy RTU via a dial-up connection is replaced by an SNMP RTU that has both LAN and dial-up capability (Figure 1).
Alarm data is collected by the RTU, reported via dial-up to a PPP server which connects to the SNMP manager.

Install a LAN connection

Step Two: Install a LAN Connection
Later, a LAN connection is installed at the remote site. The same SNMP RTU installed in Step One can be immediately transferred to LAN transport with minimal configuration-and without disconnecting alarm inputs. (Figure 2).

A dial-up connection can be retained as backup secondary connection in case of LAN failure.
You don't have to cut over all your sites at once-you can gradually migrate different sectors of your network to LAN, as your budget and installation manpower allows.

Benefits of LAN Migration

Spread the expense of installing LAN over several budget cycles. Completing a major installation in one budget cycle can strain your Cap-X and staffing budgets. With controlled migration, you control the pace of migration, so it happens as quickly or as slowly as you like.

• Minimize equipment costs. With LAN migration, you only have to buy one SNMP RTU for each of your remote sites, and it's compatible with both your old and your new transport.

Implement SNMP monitoring now at all your remote sites Without LAN migration, you'd need to maintain a separate legacy alarm monitoring system to monitor your non-LAN sites. Operating two unintegrated alarm systems is a bad idea-it means higher maintenance costs, higher training costs, and watching multiple screens to monitor your network.


Step Two: Survey Your Existing Equipment

The next step in your network assessment is determining how much of your currently existing network elements support SNMP.

As in Step One, your goal here is to collect information about your existing network so you can systematically plan what upgrades will be necessary for SNMP monitoring.

If you're lucky, much of your current equipment will already support SNMP. A lot of recently manufactured equipment is built with native SNMP support, so your newer equipment may already be SNMP-ready, even if you've never used that capability before.

LAN-based monitoring for sites without LAN access
An SNMP network element with dial-up backup can bring
SNMP monitoring to sites without LAN access.

Now let's look at your network elements that don't support SNMP. Some of these may be upgradeable. Check with the manufacturer of your equipment to see if there is an SNMP upgrade option.

The upgrade could be as simple as installing new firmware on the equipment. But you may have to replace your existing equipment with a later model that supports SNMP.

Unfortunately, for some of your equipment, upgrade options just won't be available. The manufacturer may no longer support your model, or, in some cases, the manufacturer may no longer be in business.

In those cases, you're going to have to consider replacing the equipment with something entirely new. But you have to be careful about replacing equipment - it can involve unnecessary costs.

Another potential problem is that new SNMP equipment may not be equivalent to your older equipment. Replacement may mean giving up useful features of your legacy equipment.

After completing your equipment survey, you can divide your equipment into four categories:

  1. Equipment that natively supports SNMP.
  2. Equipment that can be firmware upgraded to support SNMP.
  3. Equipment that can be swapped out for a later SNMP model.
  4. Equipment that cannot be replaced with a direct SNMP equivalent. (This is the most dangerous equipment-related pitfall - for solutions, see "High Costs of Replacing Non-SNMP Equipment" and "Losing Valuable Monitoring Capabilities," in this white paper)

Using this information, you can create a conversion plan for implementing SNMP monitoring on your network. You now have a list of what needs to be upgraded to use SNMP, and how it can be upgraded.

In combination with the transport network map you created in Step One, you should now have a complete diagram of how the network needs to be adapted to put SNMP monitoring into place.


Let DPS Help You Survey Your Network - A Free Consultation at No Obligation to You


Determining your alarm monitoring needs can be tough. If you've got a busy job with lots of

Ron Stover
Ron Stover
DPS Telecom Director of Sales

responsibilities, you don't have a lot of time to evaluate alarm systems and
survey your remote sites.

So why not get help from experts you can trust? DPS Telecom will help you survey your remote sites step-by step, making sure you don't miss any opportunities to make your network monitoring simpler, more effective - and easier on your budget.

"We're not your typical sales department," says Rick Dodd, DPS Telecom Director of Sales. "We're design consultants, and a lot of the time we propose solutions that have a smaller sales volume, if it's the right solution for the client."

A DPS expert consultant can help your figure out what alarm system will most effectively meet your needs without overloading your budget. Our goal is to help you maximize your return on investment while minimizing your expenditure - without pressuring you to buy a particular system.
There's no hard-sell sales tactics. No harassing sales calls. No pressure to buy. You won't get any equipment recommendations until we've helped you plan the right monitoring strategy for your network.



Potential Pitfall #2: High Costs of Replacing Non-SNMP Equipment (If replacement is possible!)

Another place where your SNMP implementation budget can get derailed is the sheer expense of replacing a lot of equipment.

It takes a lot to make a remote site run - not just the primary equipment, but also essential secondary equipment such as battery plants, rectifiers, generators.

And to keep full visibility of your remote site, you also need to monitor environmental factors: temperature, humidity, fire, flooding.
Your telephony gear can possibly be replaced with SNMP native equipment - at considerable expense.

But your essential secondary monitoring equipment probably has no SNMP native equivalent. You could maintain a second legacy telemetry system to monitor power and environmentals, but again, splitting your monitoring across two or more screens is not the best solution.

Fortunately, in many cases, replacement is simply unnecessary.

Proxy agent can mediate standard alarm outputs
A proxy agent can mediate standard alarm
outputs from various types of equipment to SNMP.

Your equipment does not have to natively support SNMP for you to monitor it using SNMP.

A proxy device can accept any standard alarm output and convert it to an SNMP trap.

Primary and secondary equipment that outputs discrete contact closure alarms, and power and environmental equipment that outputs analog alarms, can all be incorporated in your SNMP monitoring via the proxy device.

Interested in learning more?

For more on SNMP proxy agents, check out more white papers available online.



Step Three: Collect MIB Files for Your Equipment

After completing Steps One and Two, you should now have a plan for:

  1. How you're going to transport SNMP data from your remote sites.
  2. How you're going to ensure SNMP compatibility for your telemetry equipment.

Your next step is to make sure that you have the correct Management Information Base (MIB) files for all of your equipment.
MIB files have an elaborate inner structure, but you don't need to know too much about it to use them. The important thing to know about a MIB file is that it's a kind of dictionary or code book that is used to assemble and interpret SNMP messages.

Each type of device on your network has its own specific MIB file. The MIB file defines the device as a set of managed objects - values that can be read or changed by the SNMP manager.

The MIB file enables the SNMP manager to interpret trap messages from devices. To make sense out of a trap that's sent by a network element, the SNMP manager needs to have access to the MIB that describes the format and content of the possible traps that the element can send.

To be available for the SNMP manager, the MIB file for each of your equipment types needs to be installed on the SNMP manager, a process that's called "compiling."

The network administrator in charge of the SNMP manager can handle the chore of compiling. All you need to do is ensure that the correct MIB file for each equipment type is collected and provided to the network administrator.

This is relatively simple, because MIB files are created and supplied by equipment vendors. The MIB file should have been provided on disk with your equipment; if it can't be located, contact your equipment vendor for assistance.

MIB files are equipment specific, so it's important to make sure that you have the correct MIB for your equipment type, model, and version number. This information should be documented by your equipment vendor.


Potential Pitfall #3: Losing Valuable Monitoring Capabilities

Even if your budget will cover it, replacing your existing equipment with SNMP-native equipment is not always your best course of action. There's no guarantee that your new SNMP equipment will have the same functions, or be as capable, as the equipment it replaces.

Even if you're installing entirely new equipment, native support for SNMP shouldn't be the deciding criterion for selecting equipment.

Being locked into one telemetry protocol is just as dangerous as being locked in to one equipment vendor - it severely limits your equipment choices. And in network monitoring, not having all the features you need can limit your visibility of network problems, and possibly leave your network more vulnerable to a service-affecting outage.

If there is a piece of equipment - old or new - that meets all the other essential criteria for your network's needs, but
doesn't support SNMP, it shouldn't just be discarded.

Protocol mediation solution: mediates Non-SNMP equipment to SNMP.
A protocol mediation solution can free you to select the
equipment that's right for your network.

You can integrate many different types of equipment into your SNMP monitoring by using a protocol mediation solution.

Common telemetry protocols such as TABS, TBOS, and ASCII can all be mediated to SNMP. These protocols often provide more detailed information than pure SNMP.

With protocol mediation, you can select the equipment you want, confident that it will work with your SNMP monitoring. You can still use valuable features from existing equipment and other telemetry protocols.

And not least, protocol mediation offers a way of preserving existing equipment in place, saving your budget from more highly expensive replacement costs.


Step Four: Plan Your Migration Budget

Now that you've gone through the preliminary planning and information gathering of Steps One through Three, you can now begin planning the budget for your SNMP implementation.

Hopefully, examining your existing data transport and telemetry equipment has helped you identify areas of your network that can be preserved without upgrading.

Using migration and mediation solutions, considerable portions of your network can be made SNMP ready without the costs of wholesale replacement. This can go a long way to keeping your capital expenditure budget within reasonable limits.

But you also need to watch out for costs related to installation manpower. A complete changeover of entire systems, or "forklift swapout," can strain your personnel budget as well as your Cap-X budget.

Trying to replace large portions of your network at once can take more man-hours than you have personnel - or overtime budget - to cope with.

And buying equipment that you can't install can hurt your projects finances as well. Equipment that's sitting in a warehouse instead of operating in the field generates no return on investment.

A migration solution can help with this problem as well. You don't have to purchase more equipment than your available manpower can conveniently install within any budget period.

You'll buy only what you can use. You won't incur excessive overtime costs. And you won't be paying for the privilege of warehousing equipment for months.


Potential Pitfall #4: Manpower Costs

Forklift swapouts place a huge strain on budgets: they create high capital expenditure costs, they require man-years of billable time to install, and warehoused equipment generates no ROI.

A controlled migration to SNMP monitoring from your existing system can stretch these costs over several budget cycles, ensuring a positive balance sheet during each budget cycle.

Controlled Migration
Controlled migration lets you transition to SNMP-based alarm monitoring at your own pace.

Here's how controlled migration works:

In first phase, alarm outputs from existing telemetry equipment is re-routed to a combined telemetry master/protocol mediation device. The protocol mediation device converts the incoming data to a single stream of SNMP data, which is forwarded to an upper-level SNMP manager.

Depending on your network's individual needs, you can stop right here or you can start migrating your network to SNMP.

If you choose the migration option, non-SNMP network elements are gradually replaced by SNMP devices. Sections of the network can be cut over to SNMP as your Cap-X and purchasing budget permits, without interfering with your network monitoring.