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SNMP Tutorial: The Fast Track Introduction to SNMP Alarm Monitoring by Marshall DenHartog

Simple Network Management Protocol for real-world telecom network alarm monitoring . . . • Fast, complete introduction to SNMP • Effective telecom alarm monitoring with SNMP • Integrating legacy equipment to SNMP monitoring • Overcoming the limitations of SNMP • Enhanced security with SNMPv3

Version 2.0 Released July 21, 2010


US $36.95

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SNMP Tutorial • DPS Telecom • 4955 East Yale Avenue, Fresno, California 93727 • (800) 622-3314 • Fax (559) 454-1688 •

© Copyright 2010 DPS Telecom All rights reserved, including the right to reproduce this white paper or portions thereof in any form without written permission from DPS Telecom. For information, please write to DPS Telecom 4955 E. Yale Ave., Fresno, CA 93727-1523 • Call: 1-800-622-3314 • Email: Printed in the U.S.A

. . . . . . . . . . . 5 Reality Check: 5 Essential Capabilities for SNMP RTUs . . . . . . . . . 8 Part 6: 7 Reasons Why a Basic SNMP Manager Is a Lousy Telemetry Master . . . . . . . 6 Essential SNMP: What is the MIB? Part 4: Understanding Packet Types and Structures. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . the telecom professional who needs to monitor network alarms with SNMP. . . . . . . . 10 Case Study: KMC Telecom Saves $2 Million Per Year Through In-House Monitoring . . . . . . That’s great if you want to manage a computer network. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Part 3: Understanding the MIB ( Management Information Base) . . . . . 4 Part 2: How SNMP Handles Alarm Messages. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . California 93727 • (800) 622-3314 • Fax (559) 454-1688 • www. . . Fresno. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 SNMP Glossary. . . . . . . . . . . 5 Essential SNMP: What is a Trap. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Understanding SNMPv3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Reality Check: Why You Need Help With Your SNMP Implementation. . . 7 Part 5: Understanding Layered Communication. . . . . . . . . . . . . . . . . . but it’s useless if you need carrier-grade network visibility of telecom equipment and remote sites. . . . . . . 4 Reality Check: What Can SNMP Do for Me? . . . . . . . . . . . . . . . . . 7 Reality Check: 4 Signs You Need Protocol Mediation . . . . . . . . . . . . . . . . . . . . 16 SNMP Product Guide. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . This guidebook has been created to give you the information you need to successfully implement SNMP-based alarm monitoring in your network. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Reality Check: How to Get Better Visibility of Your SNMP Alarms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Quick and Dirty Checklist: 5 Steps to Start Your SNMP Monitoring Project. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 3 . . . . . . . Instead. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .com How This Guidebook Will Help You Most SNMP reference books aren’t written for you. . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 SNMP Troubleshooting Guide . . . . . . 19 What to Do Next. . . . . . 10 Reality Check: 7 Features That SNMP Managers Can’t Match. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Essential SNMP: What is UDP?. . . . . . . . . . . . . . . . . most SNMP books are written for IT techs. . . . . . . . . .SNMP Tutorial • DPS Telecom • 4955 East Yale Avenue. . . . . . . . . . . . . . . . . . with fast specific answers to help you make SNMP monitoring work in your network. It’s an introduction to SNMP strictly from the prospective of telecom network alarm management. . . . . . . . . . . . . . 8 Reality Check: How Protocol Mediation Works. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Contents Part 1: An Introduction to SNMP. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .dpstelecom. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

and supported by multiple vendors. LAN data transport reduces installation and operation costs and transports alarm data more reliably. 4 . SNMP has achieved widespread acceptance. SNMP is simple. can do a lot to make your network alarm monitoring more cost-effective and your network more reliable — if you clearly identify your network monitoring goals and have the right tools to achieve them. Vendors and users of SNMP equipment can add to the Management Information Base (MIB) to include nearly any kind of device. managed objects and the network protocol. Alarm messages (Traps) are sent by the agent to the manager. • It can be easily extended. such as point status or description. For a full report on 8 pitfalls to avoid. call DPS at 1-800-622-3314. SNMP is non-proprietary. Fresno. The manager and agent use a Management Information Base (MIB) and a relatively small set of commands to exchange information. You can avoid the risks (and guarantee the benefits) of your SNMP implementation by working with an experienced vendor who can help you accurately determine your network monitoring needs. This long-term solution. A long numeric tag or object identifier (OID) is used to distinguish each variable uniquely in the MIB and in SNMP messages. however. The MIB is organized in a tree structure with individual variables. but it’s also flexible enough to describe almost anything. it’s easy to wind up with a system that costs too much and does too little. INCE ITs CREATION Reality Check: What Can SNMP Do For Me? S SNMP was derived from its predecessor SGMP (Simple Gateway Management Protocol) and was intended to be replaced by a solution based on the CMIS/CMIP (Common Management Information Service/Protocol) Management System Managed Element Human Network Manager Manager Network Protocol Messages Agent Management Database Management Database Managed Objects Figure 1. SNMP is based on the manager/agent model consisting of a manager. being represented as leaves on the branches. • It’s an open standard. • It provides a common management platform for many different devices.dpstelecom. The agent provides the interface between the manager and the physical device(s) being managed (see illustration). SNMP uses a manager/agent architecture. never received the widespread acceptance of SNMP. fully documented. creating greater interoperability between different parts of your network. an agent. a database of management information. To learn more. NMP The advantages of SNMP are: • It’s LAN-based. That’s what’s good about SNMP — but there’s also some pitfalls that you have to watch out for. Part 1: An Introduction to SNMP S in 1988 as a short-term solution to manage elements in the growing Internet and other attached networks.SNMP Tutorial • DPS Telecom • 4955 East Yale Avenue. If it’s supplied with the right MIB file. The manager provides the interface between the human network manager and the management system. call 1-800-622-3314 and ask for your free Network Monitoring Needs Analysis. If you’re not careful. California 93727 • (800) 622-3314 • Fax (559) 454-1688 • www. Moving your alarm monitoring off dedicated copper lines and onto existing LAN/WAN infrastructure creates significant savings. an SNMP manager can correctly interpret alarm data from any device that supports SNMP.

or serial.LAN. Fiber. all DPS Telecom SNMP equipment transmits a unique Trap ID for both alarm and clear for each alarm point. Discrete alarm inputs (also called digital inputs or contact closures): These are typically used to monitor equipment failures. Set and Trap) to communicate between the manager and the agent. You often have to parse variable bindings to decode a Trap. Essential SNMP: What is a Trap? An SNMP Trap is a change-of-state (COS) message — it could mean an alarm. 6. Control relays: Don’t waste time and money sending a technician to a remote site miles away simply to turn a switch. analog alarms measure continuously variable levels of voltage or current. Dial-Up. You can minimize costs by getting an RTU that supports your available transport . This notifies the SNMP manager as soon as an alarm condition occurs. if an agent fails. Analog alarm inputs: While discrete alarms monitor on/off conditions. beacons. A Set message allows the manager to request a change be made to the value of a specific variable in the case of an alarm remote that will operate a relay. Terminal server function: Your RTU can also serve as a terminal server to remote-site serial and flood and fire detectors. or vice versa. 5. As you can see. To learn more about DPS Part 2: How SNMP Handles Alarm Messages SNMP UsEs FIVE basic messages (Get. GetNext.dpstelecom. intrusion alarms. The Get and GetNext messages allow the manager to request information for a specific variable. a clear or simply a status message. Within this framework. Ping alarms: An RTU that supports ping alarms will ping devices on your network at regular intervals. An RTU with control relay outputs will let you operate remote site equipment directly from your NOC. expandable alarm capacity. 5 . This simplicity has led directly to its widespread use. GetResponse. will issue a GetResponse message to the manager with either the information requested or an error indication as to why the request cannot be processed. specifically in the Internet Network Management Framework. look instead at how many alarm monitoring functions it can perform. most of the messages (Get. it is considered robust because of the independence of the managers from the agents. To make sure the meaning of a Trap is understood. providing immediate notification that the device has failed or gone offline. If a device fails to respond. Your devices connect to the RTU’s serial ports. basic SNMP managers don’t keep a standing alarm list. it is the message used by DPS Telecom remote telemetry units (RTUs) to report alarms. that is. The small number of commands used is only one of the reasons SNMP is simple. The other simplifying factor is its reliance on an unsupervised or connectionless communication link. and Set) are only issued by the SNMP manager. Because the Trap message is the only message capable of being initiated by an agent. Unlike a classic telemetry master.dpstelecom. DPS Telecom offers SNMP RTUs that meet all these requirements — and offer stand-alone local visibility through any web browser. 4. The agent will then respond with a GetResponse message indicating the change has been made or an error indication as to why the change cannot be made. instead of waiting for the SNMP manager to ask. OW DO YOU Here are 5 essential features that your SNMP RTU must have: 1. California 93727 • (800) 622-3314 • Fax (559) 454-1688 • www. T1. 2. Reality Check: What Features Do I Need in an SNMP RTU? H find the right SNMP RTU? Look for more features than just SNMP support. Many devices can output SNMP Traps — when you’re evaluating an RTU. 3. Analog alarms monitor temperature. giving you immediate Telnet access via LAN from your NOC at any time. upon receiving a Get or GetNext message. LAN access via dial-up connection and more. CDMA/GSM Wireless. request a live Web demo at www. so it’s difficult to tell what’s happening in your network by looking at a list of Traps. The agent. GetNext. the manager will continue to function. The Trap message allows the agent to spontaneously inform the manager of an “important” event. humidity and pressure. all of which can critically affect equipment performance. the RTU will send an alarm as an SNMP Trap. It supports your transport: You may not have LAN available at every site. Fresno.SNMP Tutorial • DPS Telecom • 4955 East Yale Avenue.

4. potentially resulting in serious damage to your network and your revenue. T/Mon is a multiprotocol.SNMP Tutorial • DPS Telecom • 4955 East Yale Avenue.2682... call 1-800-622-3314 today to register for a live Web demonstration or register on the Web at www. multifunction alarm master with advanced features like programmable custom alarms. it will locate the problem. The element receives the request and looks up each OID in its code book (MIB).3.1. hERE’s A BIG DIFFERENCE ccitt (0) iso (1) joint-iso-ccitt (3) org (3) dod (6) internet (1) 1. it can include OID and value information (bindings) to clarify the event. The MIB associates each OID with a readable label (e. These object identifiers naturally form a tree as shown in the below illustration. alarm filtering and silencing and more.6.1. such as the state of an alarm point. Any basic system will give you some kind of notification of an alarm. and that’s a crucial edge to have in today’s competitive telecom industry. And some problems require immediate action far faster than any human being can respond. but it’s worth the trouble. Automated Correction Your staff can’t hover around a screen watching for alarms with their full attention 24/7. The branch of the MIB object identifier tree that represents managed elements used by DPS Telecom Part 3: Understanding the MIB (Management Information Base) E element manages specific objects with each object having specific characteristics. When an element sends a Trap packet. Advanced features like these can make the difference between a minor incident and major downtime. Well-designed SNMP managers can use the bindings to correlate and manage the events. . a special error response is sent that identifies the unmanaged object. it will assemble a GET packet that includes the OID for each object/characteristic of interest. if possible. Your SNMP manager can’t monitor your devices unless it has compiled their MIB files. if your device’s MIB lists OIDs for Traps but not for GetResponse messages. DPS remote units send a comprehensive set of bindings with each Trap to maintain traditional telemetry event visibility. 1. California 93727 • (800) 622-3314 • Fax (559) 454-1688 • www.1. Figure 2. The MIB is also a guide to the capabilities of your SNMP devices.4. Learning to read MIBs is difficult.2682. you need the T/ Mon Remote Alarm Monitoring System. e-mail and pager alarm notification.g. provide instructions for corrective action. but will not respond to alarm polls. and. If the OID is not found.3. you know it will report alarms. SNMP managers will also generally display the readable labels to facilitate user understanding and 6 Essential SNMP: What is the MIB? The MIB lists the unique object identifier (OID) of each managed element in an SNMP network. Each object/characteristic has a unique object identifier (OID) consisting of numbers separated by decimal points ( When an SNMP manager wants to know the value of an object/characteristic.1 dpsAlarmControl (1) TMonXM (1) dpsRTU (2) Intelligent Notification An intelligent alarm management system won’t just tell personnel there’s a problem.1. The MIB then serves as a data dictionary or codebook that is used to assemble and interpret SNMP messages. automatic alarm correction.6.dpstelecom.g. ACH sNMP root Reality Check: How to Get Better Visibility of Your SNMP Alarms Receiving Traps is Only the Beginning of Effective SNMP Monitoring T between basic alarm monitoring and intelligent alarm management. To learn more about T/Mon. Fresno. a response packet is assembled and sent with the current value of the object / characteristic included. route alarm information directly to the people who need it. For example. If you want these features. Using a basic alarm monitoring system makes it more likely that faults will not be corrected. dpsRTUAState) and various other parameters related to the object. A simple system cannot get alarm information to the people who can correct problems quick enough to make a difference.1 directory (1) mgmt (2) experimental (3) private (4) enterprises (1) dpsInc (2682) 1.1). But simple status reports don’t provide effective full visibility of your network.6. If the OID is found (the object is managed by the element). correct the problem automatically. or the element uptime. the system name.

a type and a value (if a Set or GetResponse). You want to gradually migrate from your old system: It’s time to replace your older system . Figure 3 (above) shows the packet formats. and it’s hard to get new remotes.. which is enclosed in the IP data packet. The manager sends a Set to change a variable or variables and the agent’s response confirms the change if IP datagram UDP datagram common SNMP header PDU type (0-3) SNMP message get / set header request error status error ID (0-5) index variables to get / set IP header UDP header version community (0) name value name value . The packets contain header. California 93727 • (800) 622-3314 • Fax (559) 454-1688 • www. Protocol mediation saves you money by keeping your non-SNMP equipment in place. Part 4: Understanding Packet Types and Structure Reality Check: 4 Signs You Need Protocol Mediation 1. You inherited someone else’s incompatible system: If your company has merged with another. UDP does not guarantee message delivery. do a site survey and find out how much non-SNMP equipment you have in your network. 7 . data and checksum bytes. The agent sends a Trap when a specific event occurs. The SNMP data packet is enclosed in the UDP data packet. but it’s a lightweight protocol that can transport a large number of status messages without using too many network resources. The manager uses its MIB to display the readable name of Essential SNMP: What is UDP? UDP (User Datagram Protocol) is the IP transport layer protocol that supports SNMP messages. Each variable binding contains an identifier. If you have a large network. but you need to integrate it into your existing operations. 4.the master is starting to fail. with a single byte exchanged to communicate. A UDP host places messages on the network without first establishing a connection with the recipient. You don’t want to pay license fees: You may have to pay a separate license fee for every device you monitor with your SNMP manager. are packet oriented with packets of bytes exchanged to communicate. Protocol mediation lets you integrate your old remotes with an SNMP manager. You can’t afford to replace this network.. Fresno. like TBOS. are byte-oriented. like TABS. you might find yourself responsible for a whole new network of incompatible equipment. L the communication between managers and agents. A protocol mediator can take input from your whole network and consolidate it to one SNMP input. so you can replace your legacy system step by step. Unlike TCP. Changing out a large number of non-SNMP devices can add hundreds of thousands of dollars to your project costs. decision-making. SNMP is also packet oriented with the following SNMP v1 packets (Protocol Data Units or PDUs) used to communicate: ET’s EXAMINE Get GetNext Set GetResponse Trap The manager sends a Get or GetNext to read a variable or variables and the agent’s response contains the requested information if managed. But you can’t afford a forklift swapout of your whole system. Basic serial telemetry protocols. Figure 3. 2. You have a lot of non-SNMP equipment: Before planning your SNMP implementation. that can get real expensive real fast. UDP is a connectionless protocol. Protocol mediation will merge your two networks at minimal expense. Expanded serial telemetry protocols. The agent checks each identifier against its MIB to determine whether the object is managed and changeable (if processing a Set).dpstelecom. 3.SNMP Tutorial • DPS Telecom • 4955 East Yale Avenue. at only one license fee.

NetMediator For central-office mediation. which in turn is wrapped in the Internet Protocol (IP). including SNMP Traps. v2c. T/Mon collects alarms from many different types of equipment and protocols. Traversing the Layers To illustrate the function of this layered model. let’s look at a single SNMP GET request from the agent’s 8 Set . enabling you to monitor all your equipment from your SNMP manager. analog and ping alarms. California 93727 • (800) 622-3314 • Fax (559) 454-1688 • www. and DACs. The fourth layer is the Network Interface layer where the assembled packet is actually interfaced to some kind of transport media (for example. It is wrapped in the User Datagram Protocol (UDP). RG58 co-axial or fiber). mediates all alarm data to a common format. NetGuardian 832A plus it can mediate TBOS and TABS alarms to SNMP. DPS Telecom offers the NetGuardian 832A and the NetMediator. either for your central office or equipment in the field. contact DPS Telecom’s Sales Engineers at sales@dpstele. ROtOCOL MEDIAtION SNMP resides in what is called the Application layer. These are commonly referred to as layers and are based on a four-layer model developed by the Department of Defense (you may recall the DoD origins of the Internet). E CONTINUE P converts legacy alarms to SNMP Traps. DNP3. or v3) to multiple SNMP managers. An SNMP message passes through the protocol layers at both the manager and agent. The NetGuardian is an SNMP-based remote telemetry unit that accepts inputs from discrete. UDP resides in the Transport layer and IP resides in the Internet layer (somewhat obvious). ASCII. then forwards the data as SNMP Traps (v1. communication and ultimately assists in designing and implementing a network. and can forward alarm data to other devices in a wide variety of protocols. While this multi-layer model may seem a bit confusing. including Modbus. If you are mediating alarms from SNMP to other protocols. the correct solution is to mediate Traps from the SNMP devices into the protocols used by your existing master. you most likely are collecting SNMP Traps from diverse equipment at various sites. and the variable and sometimes interpret its value.SNMP Tutorial • DPS Telecom • 4955 East Yale Avenue. twisted pair copper. you may have a non-SNMP master that is deeply embedded in your network. and also avoids the trouble and costs of installing and maintaining a specialized SNMP manager to monitor only SNMP equipment. Part 5: Understanding Layered Communication A Critical Tool for Troubleshooting Communication Problems Reality Check: How Protocol Mediation Works W to examine the Simple Network Management Protocol (SNMP) focusing specifically on the layered communication model used to exchange information. For help with protocol mediation devices. This solution is more practical and less expensive than replacing your existing master. Each layer does a specific communication task. Fresno.dpstelecom. the T/ Mon Remote Alarm Monitoring System serves as a general protocol mediation solution. routers. The last section focused on the structure of SNMP messages. it effectively isolates the tasks of SNMP Management System SNMP Managed System Managed Resources SNMP Managed Objects GetResponse Get-Next Event Mediating other protocols to SNMP For remote-site mediation. You need a central office mediation solution that will collect the incoming Traps in one place and mediate them all to different protocols before forwarding them to the higher level or 1-800-693-0351. Communications Network Figure 4. Management Application Get-Next GetResponse Event Get Set Application Manages Objects Get SNMP Manager UDP IP Link SNMP Messages SNMP Agent UDP IP Link Mediating SNMP to Other Protocols Alternatively. however an SNMP message is not sent by itself. but you need to monitor native SNMP devices like switches. In that case. The NetMediator includes all the local site monitoring capabilities of the NetGuardian.

the Network Interface layer simply passes it to the IP layer. Each step can be verified independently until all steps are working correctly for end-to-end communication. The SNMP manager wants to know what the Agent’s System Name is and prepares a GET message for the appropriate OID. First. The IP layer verifies the Media Access and IP address and passes it on to the UDP layer where the target port is checked for connected applications. After working its way across bridges and through routers (the modern equivalent of over the rivers and through the woods) based on the IP information. the GET request is processed as we have discussed in previous articles. SNMP is an applications-layer component of the TCP/IP suite of protocols perspective. The agent response then follows the identical path in reverse to reach the manager. you can simply trace it down. At a DPS Factory Training Event. The packet thus formed is then passed to the IP layer. 9 . LAN/WAN link and activity status indicators provide some visibility to the Network Interface layer. When there is a problem. the packet is passed to the Application layer. Fresno. and up the other. If the listening application is the SNMP agent. The UDP layer adds a data block that identifies the manager port to which the response packet should be sent and the port on which it expects the SNMP agent to be listening for messages. The Network Interface layer verifies media access and availability and places the packet on the media for transport. Troubleshooting IP Communication Problems Understanding this layered model makes it easier to troubleshoot communication problems. Application Layer Transport Layer Internet Layer Network Access Physical Layer SNMP SMTP UDP IP PPP Telnet HTTP TCP FTP ICMP SLIP USART ARP Ethernet Modem Figure 5. It’s the easiest and most complete way to learn SNMP alarm monitoring from the technicians who have designed hundreds of successful SNMP monitoring implementations For Factory Training Events dates and registration information.dpstelecom. I’m not at all scared about SNMP now. call 1-800-693-3314 today or visit us on the Web at http://www. configuring and using derived alarms and controls. ICMP echo requests and responses (PINGs) provide some information regarding the proper functioning of the IP layer. SNMP processing indicators can be used to verify the passage of the packet through the UDP layer and the functioning of the Application and automatic e-mail and pager notifications. It then passes the message to the UDP layer. in a totally practical class that will teach you how to get the most from your network monitoring. but I never knew what SNMP was until I learned it at DPS Factory Training. it is pulled off the media by the Network Interface layer. EARN Each 4-day training course covers SNMP alarm monitoring ASCII alarm parsing and processing. If an application is listening at the target port.” —Derek Willis. SNMP’s location in the TCP/IP protocol stack. Paul Bunyan Telephone L SNMP IN-DEPTH and hands-on. After confirming that the packet is intact and valid. How to Learn SNMP the Easy Way: Attend DPS Telecom Factory Training “I had heard of SNMP.dpstelecom. you’ll learn how to turn SNMP theory into a practical plan for improving your network visibility.SNMP Tutorial • DPS Telecom • 4955 East Yale Avenue. the packet finally arrives at the agent. California 93727 • (800) 622-3314 • Fax (559) 454-1688 • www. Here it passes through the same four layers in exactly the opposite order as it did at the manager. Here a data block containing the IP and Media Access addresses of the manager and the agent is added before the entire assembled packet gets passed to the Network Interface layer. out one end.

com Part 6: 7 Reasons Why a Basic SNMP Manager Is a Lousy Telemetry Master S protocol that has wide acceptance in the industry and is flexible enough to describe almost anything. Every notification includes full information about the alarm. an off-the-shelf SNMP manager will not provide the detailed alarm data you expect. The typical off-the-shelf SNMP manager is not designed for displaying and processing telemetry data.SNMP Tutorial • DPS Telecom • 4955 East Yale Avenue. Detailed alarm notifications in plain English that your staff will immediately understand and take action on. will know precisely what to do and who to call in case of an alarm. severity or descriptions of alarm events. you must create and maintain a master alarm list representing all the monitored points in your network — and then also create and maintain a database associating all the Traps that may be sent to the SNMP manager with the alarms on that list. Easy to Use Web Interface that provides quick access to alarms for technicians on the go. Nuisance alarm filtering. Creating this addition to the Trap association database often requires analyzing multiple variable bindings within the Trap packet. Unimportant alarms that generate meaningless status notices or oscillate between alarm and clear conditions subconsciously train your staff to ignore the alarm monitoring system. Before you buy … check for these 7 essential telemetry features: 1. date/ time stamp. but it may require substantial custom software development. time. California 93727 • (800) 622-3314 • Fax (559) 454-1688 • www. location.dpstelecom. either by laptop or smartphone. 7. 5. allowing your staff to focus its attention on serious threats. Send alarm notifications directly to maintenance personnel. A continuously updated list of all current standing alarms. SNMP certainly has its place in an effective telemetry monitoring solution. 2. you need to make sure it supports essential telemetry functions. 6. Fresno. T/Mon filters out nuisance alarms. many network managers have come to believe that SNMP should be used for all telemetry monitoring applications. and a user-defined description. 2. but this doesn’t mean that any off-the-shelf SNMP manager can provide adequate visibility and control of your network. 4. Derived alarms and controls that combine and correlate data from multiple alarm inputs and automatically control remote site equipment to correct complex threats. Because of these advantages. NMP Is A sTANDARD Reality Check: 7 Features That SNMP Managers Can’t Match 1. System operators. Before you commit to an SNMP monitoring solution. including its severity. especially not for the kind of real-world monitoring tasks network managers most need performed. precise alarm descriptions A basic SNMP manager doesn’t record location. To adapt an off-the-shelf SNMP manager to monitor these factors. Text message windows displaying specific instructions for the appropriate action for an alarm. Pager and e-mail notifications. Even if the system operator acknowledges the alarm. Basic SNMP managers can’t identify cleared alarms Even more work is required to identify whether a Trap represents an alarm or a clear condition. 10 The T/Mon Remote Alarm Monitoring System provides total visibility of your network status and automatically notifies the right people to keep your network running. including new alarms and alarms that have cleared. Using off-the-shelf SNMP systems for mission-critical telemetry is disappointing at best and disastrous at worst. it remains in the Standing Alarms screen until it is cleared. 3.dpstelecom. even if they’re away from the NOC. If you’re used to the standards of classic telecom telemetry. You don’t have to hunt to find out what’s changed in your network — T/Mon lists it for you. These capabilities can be added to an SNMP . Immediate notification of changes of state (COSs). Sign up for a Web demo of T/Mon at www. even without extra training. Basic SNMP managers don’t provide complete. 8.

All Traps are posted to one alarm 11 . and it is difficult to justify significant development costs after purchasing an already expensive SNMP manager. legacy protocol mediation. the other manager needs to know it was acknowledged and by whom. but neither one needs to know about all the alarms in the network. but not all. Imagine what might happen to your network if a system operator acknowledges an alarm. they usually require custom tweaking to perform exactly as you want them to. Even when pre-built software modules are available. SNMP-capable network alarm management system? And in fact. fails to correct the alarm condition. and expense to recreate capabilities that are already present in a high-quality. And if one manager corrects the alarm condition and acknowledges the alarm. and then. Basic SNMP managers are insufficiently secure for multiple users Out of the box. A basic SNMP manager doesn’t maintain a list of standing alarms. California 93727 • (800) 622-3314 • Fax (559) 454-1688 • www. and all users may acknowledge all alarms. For details about an alarm management system that overcomes these 7 barriers . As soon as a Trap is acknowledged. it would be impossible to determine who had made the mistake or to assign responsibility for the resulting 3. 5. for whatever reason. posting the same alarm to multiple logical categories. but it’s only one item in your telemetry monitoring toolkit. Why take the time. Basic SNMP managers don’t maintain a history of standing alarms Relying on a basic SNMP manager for alarm management can potentially result in completely losing visibility of threats to your network. the typical SNMP manager is not designed for multi-user security. SNMP is an effective tool.dpstelecom. and automatic notifications by pager and e-mail. such as notifications escalation. It is true that many. or sorting which alarms the user wants to see. all users may view all alarms. and it can be used more effectively when it is part of a total alarm management solution. Basic SNMP managers don’t sort or filter alarms Basic SNMP managers have no built-in functions for organizing alarms by logical category. Basic SNMP managers don’t provide the alarm notification you need No SNMP manager supports the advanced features necessary for best quality telemetry monitoring. it is considered cleared. nuisance alarm silencing. the typical SNMP manager maintains an event log of newly reported Traps and a history log of acknowledged Traps. Instead. it is much easier to adapt a traditional telemetry master to process SNMP Traps than to adapt an SNMP manager to perform telemetry functions. trouble. Unfortunately. standard SNMP managers will not support these functions. of these functions can be added to standard SNMP managers. and Smith is in charge of power plants. In the example of the negligent system operator. both need to know about a generator failure in Tucson. send an email to: solutions@dpstelecom. 7. but implementing telemetry monitoring in a basic SNMP manager usually involves a substantial amount of custom software module development. If Jones is in charge of all equipment for the Western region.SNMP Tutorial • DPS Telecom • 4955 East Yale Avenue. 6. There is no question that SNMP is right for many applications. Fresno. Who would know the alarm is still standing? 4. Basic SNMP managers don’t identify system operators Basic SNMP managers do not record the identity of the system operator who acknowledges an alarm. and it is clear that SNMP will be increasingly used in the future. The need for extensive customization eliminates the advantage of using a simple open standard. automatic control relay operation.

KMC has saved substantially on operations costs while creating a real-time monitoring capability that proved itself during November’s tornado strike. Fresno. a fast-growing integrated provider of voice. Ala. This should give you some idea of the scope of KMC’s operations. where they monitor the integrity of KMC’s fiber optic network as well as environmental. Huntsville.000 alarm Case Study: KMC Telecom saves $2 million per year through in-house monitoring W someone to do something you can do yourself? That was the question KMC Telecom.SNMP Tutorial • DPS Telecom • 4955 East Yale Avenue. altogether. “For most start-ups. In reliable hands: KMC Telecom’s team now has total control at their finger tips. The total project resulted in about $2 million a year in savings. KMC created a highly successful network operations center in Huntsville.” The Huntsville NOC relies on the alarm collection capacity of DPS Telecom’s NetGuardian. We now have a common interface for our existing system. where it is displayed using HP OpenView internet usage manager software. We’re looking at cost savings and how to integrate costs. ” 12 . Until last year KMC relied on an outsource provider to monitor its fiber optic network.dpstelecom. HY PAY KMC’s move from outsourced to in-house monitoring was one more milestone in the telecom’s growth from start-up to major-league CLEC. KMC had outsourced network monitoring since the foundation of its fiber optic network in the mid-1990s.” Moses says that operating its own NOC has saved KMC millions. the Huntsville NOC monitors approximately 3. “We’ve cut the operational expenses significantly. But as the network grew. California 93727 • (800) 622-3314 • Fax (559) 454-1688 • www. it’s not economical to do these things for yourself. KMC has deployed 60 NetGuardians and 120 NetGuardian Expansions. Moses says the decision to use the NetGuardian came from knowledge of the quality of older DPS Telecom products and research into current alarm monitoring offerings “ DPS Telecom gives us a reliable way of accessing a variety of equipment. which stretches over 30. KMC decided it could save money by monitoring their network themselves. and Internet services. They no longer have to pay for outsourced monitoring and are finding their response times to netdirector of operations for KMC in work outages have improved now that they can view alarm events in real-time. The NetGuardian equipment was a part of that. power. data.” says Harold Moses. it became more and more practical for us to take monitoring in house. “ It’s really added to our peace of mind to be able to see what’s going on real-time ” “We’d outsourced our monitoring since we deployed our facilities network. The growth of the company and its network had by 2001 created a situation where it was both possible and necessary to use economies of scale to cut operational costs. Since the Huntsville NOC began operation. and security alarms in KMC’s numerous remote sites. Monitor data from the NetGuardians is sent as SNMP Traps to the Huntsville NOC. asked itself in 2001. KMC has NetGuardians in 48 different locations across the United States. regardless of the brand or provider.000 miles across 35 states.

Pennsylvania. the NetGuardian was the solution that made the most sense for cost and capability. including encryption to protect the contents of any intercepted traps. the SNMPv3 protocol was designed with greater flexibility than previous versions. Privacy The other of the two SNMPv3 security types. a part of the Universal Security Model (USM). in terms of the various software options and terminal capacity. Ohio. “NetGuardian was the only solution that met both our technical and our budget needs. Outsourced monitoring can’t see problems in real time. The “EngineID” Unique Identifier The EngineID in SNMPv3 uniquely identifies each SNMP entity.” Monitoring the network in-house has also improved KMC’s monitoring visibility in ways that integrated with the way we are impossible to accomplish with a third-party provider.SNMP Tutorial • DPS Telecom • 4955 East Yale Avenue. ” Understanding SNMPv3 SNMPV3 FEATURES several enhancements over earlier versions. If you don’t need the security. Authentication Authentication is one of two types of security available in SNMPv3. and Tennessee. work. “DPS Telecom gave us a reliable way of accessing a variety of equipment. regardless of the brand or provider.” Stinson says. The key is shared with the inteneded recipient and used to receive the message. manager of the Huntsville NOC. SNMPv3 encrypts messages using CBC-DES encryption. We thought that the NetGuardian had a lot of flexibility.” says Stinson. SNMPv4? In an effort to reduce the need for future versions of SNMP. Privacy is especially useful in applications where SNMP messages must be routed over the Internet. “Nine out of 10 of these sites are unmanned. “The NetGuardian is tightly integrated with the way we work. The deciding factor was that the NetGuardian gave KMC a cost-effective means of using its existing equipment. Ultimately. but we still need to send a technician to the site. 11. but security is the most significant in the majority of SNMP applications. “ “It’s really added to our peace of mind to be able to see what’s going on real-time. Privacy encrypts the payload of the SNMP message to ensure that it cannot be read by unauthorized users. SNMPv3 can be the secure network management solution you need. As messages are created. Being able to do realtime in-house monitoring probably shaved 30 minutes off our response from a number of vendors. The EngineID is used to generate the key for authenticated messages. Any intercepted traps will be filled with garbled characters and will be unreadable. This is expected to make the lifespan of SNMPv3 longer than its predecessors.” says Moses. you’re probably best running an earlier version that is simpler to maintain. It would have taken us several minutes longer to respond if we were still using outsourced monitoring. but you must be prepared for the additional processing time required to calculate EngineID’s during authentication and encrypting/decrypting Privacy-enabled messages. “We have automatic backup generators. Tornados had ripped through Alabama. you must decide if the enhanced security of SNMPv3 is worth the cost in your application. The Cost of Security Nothing is free.dpstelecom. The real-time monitoring capability was of great service on the morning of Nov. It is used to ensure that traps are read by only the intended recipient. Fresno. Conflicts can occur if two SNMP entities have duplicate EngineID’s.” Stinson says.” Traps and its tight integration with HP OpenView. knocking out the commercial power supply to several KMC Telecom sites. We did quite a lot of research of what was available. SNMPv3 messages may be protected in 2 ways. California 93727 • (800) 622-3314 • Fax (559) 454-1688 • www. According to Dale Stinson. We now have a common interface for our existing system. in how it handles SNMP Traps and its tight integration The NetGuardian is tightly with HP OpenView. they are given a special key that is based on the EngineID of the entity. Mississippi. 13 . in how it handles SNMP Stinson adds.

dpstelecom. checking for what you already have that’s compatible with SNMP. 0 Survey Your Existing Data Transport 0 The biggest challenge in your SNMP implementation is ensuring you have enough bandwidth for SNMP traffic. overhead channel. Identify existing transport and identify what adjustments need to be made. the more you’ll save on capital expenditures. channel bank. Check for SNMP-ready transport: LAN. model. keeping your budget within reasonable limits . Fresno.SNMP Tutorial • DPS Telecom • 4955 East Yale 5 Steps You Can Take Today to Start Your SNMP Monitoring Project Quick and Dirty SNMP Checklist 0 Assess Your Existing Network Start with a thorough assessment of your exiting network equipment and data transport. 0 Plan Your SNMP Implementation Budget 14 Watch out for the capital expenditure and installation manpower costs of a forklift swapout. California 93727 • (800) 622-3314 • Fax (559) 454-1688 • www. MIB files are equipment specific. This will avoid the costs of a systemwide replacement. order wire or PPP over a dial-up or direct link 0 Make sure transport has adequate bandwidth for UDP traffic 0 Check if low-bandwidth transport can be rerouted to high-bandwidth 0 Survey Your Existing Equipment 0 0 0 0 Determine how much of your currently existing network elements support SNMP. The MIB file enables the SNMP manager to interpret Trap messages from devices. Use protocol mediation solutions to make your existing network SNMP ready. so it’s important to make sure that you have the correct MIB for your equipment type. The more you can keep. Examine your present telemetry map. so you can plan systematically what upgrades will be necessary for SNMP-based monitoring Equipment that natively supports SNMP Equipment that can be firmware upgraded to support SNMP Equipment that can be swapped out for a later SNMP model Equipment that cannot be economically replaced with a direct SNMP equivalent (Don’t replace this equipment — look for a protocol mediation solution instead) 0 Collect MIB Files for Your Equipment Make sure that you have the correct Management Information Base (MIB) files for all of your equipment. and version number.

Reconfigure firewall to allow UDP traffic at Port 162 (or port used by your SNMP manager) 0 Use packet sniffer at SNMP manager end to make sure Trap PDUs are arriving at 0 If Trap packets are arriving. If your RTU is a DPS Telecom unit. Fresno. California 93727 • (800) 622-3314 • Fax (559) 454-1688 • www.SNMP Tutorial • DPS Telecom • 4955 East Yale Avenue. check the firewall configuration. If the ping is Not getting Traps from your SNMP RTU? Here’s some quick troubleshooting steps to isolate the problem: SNMP Troubleshooting Guide 0 Check RTU configuration 0 Is the Trap address set to the correct IP address for the SNMP manager? 0 Is the RTU configured to send Traps to Port 162? (Port 162 is the standard port for receiving SNMP Traps — if your SNMP manager uses a different port. 0 If RTU configuration is correct. Consult your network administrator. use the Analyze mode of your included configuration software. make sure all devices are configured for the same port) 0 Are all alarm points on the RTU configured to send Traps? 0 Does the Trap community string on the RTU match the Trap community string on the SNMP manager? 0 Use packet sniffer at RTU end to make sure Trap PDUs are sent. check network communication between the SNMP manager and the RTU 0 Ping the RTU from the SNMP manager the manager. check SNMP manager configuration 0 Double-check Trap community string settings 0 Make sure that the right MIB file for the RTU has been compiled on the SNMP manager 0 If no Trap packets are arriving at the SNMP manager. proceed to the next step. there is an error in the network settings. If no packet sniffer is available. 15 .dpstelecom.

com SNMP Glossary Agent: A hardware device or software program that reports to an SNMP manager. Event: In SNMP terms. but other network devices like switches. EngineID: In SNMPv3. Community string: An SNMP security password. like alarm status. In SNMP terms. This is more robust than a standard trap and offers better reliability. like the SNMP Agent software module in T/MonXM. In network alarm management. An SNMP agent can also be a subsection of a larger device. Authentication: An SNMPv3 security measure that ensures that only the intended recipient receives the SNMP message. etc. any change of status in a managed object in the network. The manager can issue Get. SNMP runs over UDP. Inform Notification: An SNMP message (supported in some v2c and v3 implementations) that is similar to a trapbut requires a confirmation response from the manager. but it also consumes more network resources. Managed Objects: Values of network devices that can be read or overwritten by the SNMP manager. An entity may send an empty message to another entity to request its EngineID prior to initiating communication. The GetNext request retrieves the value of the managed object one number after the OID listed in the request. system uptime. Compiling: The process of importing a MIB file into an SNMP manager. every network device is defined in the MIB as a set of managed objects. which mediates T/Mon alarms to SNMP traps. not all of which are important for telemetry. To monitor SNMP devices.SNMP Tutorial • DPS Telecom • 4955 East Yale Avenue. COS (Change of State) alarm: A telemetry alarm that is clearly labeled as reporting a change in status from clear to alarm or from alarm to clear. Management Information Base (MIB): The MIB is a data structure that describes SNMP network elements as a list of data objects. Fresno. routers and hubs can also act as SNMP agents. Secret authentication keys are generated based upon the EngineID of the SNMP entity. Internet Protocol (IP): the network layer datagram protocol of the TCP/IP protocol suite. an SNMP agent is typically an RTU. used to walk down a range of OIDs. GetNext: An SNMP message issued by a manager. GetNext and Set requests to agents and receives GetResponse and Trap 16 . SNMP equipment can generate traps for many different kinds of events. a unique identifier for each SNMP entity. Manager: A top-level SNMP master system (hardware or software) serving as the human interface to the SNMP network.dpstelecom. To compile properly. Write Community: Allows an SNMP manager to issue Set messages Trap Community: Allows an SNMP agent to issue Trap messages. GetNext or Set request from the SNMP manager. a MIB file must be formatted in a text file according to the Structure of Management Information (SMI) standard. your SNMP manager must compile the MIB file for each equipment type in your network. There are three kinds of community strings: Read Community: Allows an SNMP manager to issue Get and GetNext messages. The ability to filter unimportant events is essential for high-quality SNMP alarm management Get: An SNMP message issued by a manager that requests the status of a managed object. control relay status. California 93727 • (800) 622-3314 • Fax (559) 454-1688 • www. which in turn runs over IP. GetResponse: SNMP message issued by an agent in response to a Get.

An OID consists of a series of numbers separated by decimal points. Referenced (RFC) MIBs: MIBs that are required by the main MIB during compiling. internet (1). Devices that mediate other alarms in other protocols to SNMP. Privacy encrypts the message contents using a key. Ports 161 and 162: The virtual ports most commonly used to transmit SNMP messages. NMS: Network Management Software or Network Management System. like the NetGuardian 832A. Privacy: An SNMPv3 security measure.1. Proxy agent: An SNMP agent that translates non-SNMP messages and inputs to SNMP. all OIDs for DPS Telecom equipment begin with the numbers 1. Set. UDP. For example. If any of these referenced MIBs are missing. UDP uses fewer network resources than TCP. GetResponse and Trap.2682. dod (6). Trap: An SNMP message issued by an SNMP agent that reports an event. dpsInc (2682).4. enterprises (1). a proxy agent is usually an RTU that converts contact closure inputs to SNMP traps. Simple Network Management Protocol (SNMP): the standard TCP/IP protocol for managing IP network devices. Standing alarm list: A list of all uncleared alarms. org (3).6. There are 5 types of PDU in SNMP v1: Get. However. Packet Internet Gopher (PING): An ICMP (Internet Control Message Protocol) echo request to determine whether a device on an IP network is online. UDP is a connectionless protocol that does not guarantee delivery of the data packet.3.SNMP Tutorial • DPS Telecom • 4955 East Yale Avenue. Protocol Data Unit (PDU): An SNMP message. Object Identifier (OID): A number that uniquely identifies a managed object in an SNMP network. Transmission Control Protocol (TCP): the more common transport layer protocol in the TCP/IP suite. private (4). like the NetMediator T2S (TBOS to SNMP) is also a proxy agent.dpstelecom. GetNext. Standard SNMP managers automatically delete all acknowledged traps. the main MIB will not compile properly. This sequence represents: iso (1). guaranteeing delivery. Each decimal point represents a leaf node in the tree structure of the MIB. Set: An SNMP message issued by a manager instructing an agent to change a Managed object to a new value SHA: One process for generating authentication/privacy keys in SNMPv3 applications. but a standing alarm list displays every alarm that has not been reported as cleared by the monitoring equipment. In network alarm monitoring. MD5: One process for generating authentication/privacy keys in SNMPv3 applications. Another term for SNMP manager software or messages. Fresno. making it more suitable for transporting a large number of status messages. Variable Binding: the data field of a GetResponse or Trap PDU. Port 161 is used for messages sent by the manager. Structure of Management Information (SMI): the standard that defines the MIB structure. 17 . TCP is considered a “reliable” protocol because it establishes a connection between the host and the recipient. Each variable binding lists a managed object and its current value. so the contents of intercepted messages will not be readable. and Port 162 carries messages sent in the opposite direction from agents.1. Unlike TCP. User Datagram Protocol (UDP): the transport layer protocol used to send SNMP messages. the transport protocol used for SNMP does not establish a connection or guarantee delivery. as maintained by a full-featured network alarm management system. California 93727 • (800) 622-3314 • Fax (559) 454-1688 • www.

Supports up to 64 devices and 7. Available SNMP software: T/MonXM SNMP Agent Software Module: Forwards T/Mon alarms in SNMP. Features pager and email alarm notification. displays as standard T/Mon alarms. alarm history SNMP Monitoring Solutions from DPS Telecom Trap Processors Remote Telemetry Units NetGuardian 832A: RTU monitors 32 alarm points. T/MonXM SNMP Trap Processor Software Module: Receives SNMP traps. reports in SNMP. standing alarm list and alarm history logging. California 93727 • (800) 622-3314 • Fax (559) 454-1688 • www. reports in SNMP. 32 ping targets. reports in SNMP T/Mon LNX: Full-featured alarm master for up to 1 million alarm points. standing alarm list. Web Browser access. T/Mon SLIM: Light capacity regional alarm master.500 alarm points. NetMediator T2S: Protocol mediator converts 8 TBOS ports. 8 analog inputs. 2 control relays.SNMP Tutorial • DPS Telecom • 4955 East Yale Avenue. pager and e-mail alarm notification.dpstelecom. 4 controls. reports in SNMP. 8 control relays. and 8 analog inputs to SNMP. Features support for 25 protocols. NetGuardian 216: RTU monitors 16 alarm points. Fresno. 4 control relays. Remote Alarm Block 176N: Wire-wrap alarm block monitors 176 alarm points. 2 analog inputs. NetGuardian 480: RTU monitors 80 alarm points. 1 terminal server port. protocol mediation. 32 alarm points. multi-user access. 4 terminal server ports. 8 terminal server ports. 8 control relays. Call 1-800-622-3314 for price and ordering information 18 . Web Browser access. alarm forwarding.

and check for client testimonials. and you have a lot to learn if you want a successful implementation. . Implementation time is drawn out: It’s going to take longer than you think.) DPS Telecom monitoring solutions are proven performers under real-world conditions. you may replace equipment that could have been integrated into your new system. . and transportation companies. software. You’re never taking any risk when you work with DPS Telecom. there’s a lot more you need to know. Call 1-800-622-3314 today to schedule your free Web demo of SNMP monitoring solutions — or register on the Web at www. no-risk. Get the information you need — register now for a free. specifications. utility telecoms. There’s no obligation to buy — no high-pressure salesmen — just straightforward information to help you make the best decision about your network monitoring. Above all. Rushing into a systemwide replacement when you could have integrated can cost you hundreds of thousands of dollars. find a few vendors.dpstelecom.dpstelecom.dpstelecom. (Check out www. 19 . Test your DPS monitoring solution at your site for 30 days. Many telecoms design what they think is a state-of-the-art monitoring system — and then find that their technology is actually a generation behind. money-back guarantee. how many protocols they can integrate to SNMP. Don’t take a sales rep’s word that his company can do custom development. features and benefits . specific applications. you are bound to make mistakes — mistakes that extend your time and your budget beyond their limits. Your SNMP monitoring solution is backed by a 30-day. Fresno. Be skeptical. developing a network monitoring system on your own is one of the riskiest things you can do. 2. compare a few features. don’t take chances. DPS Telecom has created hundreds of successful SNMP monitoring implementations for for some examples. DPS Telecom Guarantees Your Success — or Your Money Back When you’re choosing a network monitoring Reality Check: Why You Need Help With Your SNMP Implementation I SNMP network alarm monitoring system can seem deceptively easy — you just look on the Web. And anytime you are trying to do something you’ve never done before. 3.SNMP Tutorial • DPS Telecom • 4955 East Yale Avenue. just send it back for a full refund. plus you’ll be able to ask questions and get straight answers. You’ll get complete information on hardware. California 93727 • (800) 622-3314 • Fax (559) 454-1688 • www. Resources are misused: If you’re not fully informed about your options for mediating legacy protocols to SNMP. Here are some of the typical problems you might face if you don’t get expert advice when you’re designing your system: 1. Network monitoring is a highly technical subject. right? MPLEMENtING AN The truth is. Ask the hard questions. Opportunities are missed: If you install a new network monitoring system you’re committing your company to that system for as long as 8 to 10 years. Ask how many systems they’ve worked with. What to Do Next Before you make a decision about your SNMP monitoring. If you’re dissatisfied for any reason. add some configuration and you’re done. There’s dangers you want to avoid — and there’s also opportunities to improve your remote site maintenance that you don’t want to miss. live Web demonstration of SNMP monitoring solutions with the T/Mon Remote Alarm Monitoring System. look for experience.

www. creating SNMP systems for multiple platforms. Pathnet About the Author Marshall DenHartog has 12 years’ experience working with SNMP.SNMP Tutorial • DPS Telecom • 4955 East Yale “I would personally like to let you know how beneficial the installation of the SNMP responder was to the mission of our department.” —Lee Wells.dpstelecom. DenHartog’s experience with both the theoretical and practical sides of SNMP have equipped him to write a straightforward guide to SNMP for real-world use. including designing private MIB extensions. and developing SNMP-based monitoring for several nationwide networks. Fresno. and I believe that is what DPS is all about. EATEL “It is hard to find companies with the intelligence and aptitude to meet the customer’s exact 1-800-622-3314 US $36.95 “We protect your network like your business depends on it”TM . The SNMP responder was the answer. This migration will allow us not only to monitor all alarms in one spot but also build extensive collection reports of our whole network.” —Todd Matherne. We were looking for a way to integrate our local ILEC region in HP OpenView without a major network change. California 93727 • (800) 622-3314 • Fax (559) 454-1688 • www.dpstelecom.