White paper - Simple Network Management Protocol

1    Introduction

A big challenge in developing monitoring or configuration software for new hardware products is testing. Testing on a newly designed hardware device requires the device to be available and not only does the hardware need to be developed and produced, but the embedded software also needs to be operational before reliable tests can be performed. Therefore, testing can only be started very late in the development cycle.
If the communication interface with the device can be locked early in the design, testing can be done using simulators. These can then be used to return meaningful values long before the first device is build. A well designed simulator can later be used with data recorded from actual devices, or to mimic behaviour that could otherwise not be easily replicated.
At Newtec, such monitoring software uses the Simple Network Management Protocol (SNMP) to interact with their hardware components. This paper discusses how such an SNMP simulator was developed specifically for Newtec’s needs. It will explain which type of application and input methods were used, some implementation specifics, and how the tool can later be extended if more functionality are needed.

2    Introduction to SNMP

Simple Network Management Protocol is an internet-standard protocol for managing or monitoring managed network devices. With this, a device runs an SNMP agent which can respond to SNMP requests sent by an SNMP manager.
The information/variables that can be requested from a device consists of three parts: its OID (object ID), type and value.

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