What is SNMP and how does it contribute to infrastructure monitoring?
The time has come when you need to know what happens inside the company’s network. The SNMP can help you with this. In general, any network asset has the ability to communicate via SNMP because it is a standard protocol in the industry. If you still do not know it, read on and understand better how it works!
What is SNMP?
Described in the 1988 RFC 1067, it is presently in its version 3. RFC is the abbreviation for Request for Comments, a technical document by the (open standards organization) Internet Engineering Task Force (IETF), which specifies the standards implemented and used on the World Wide Web.
SNMP was created to facilitate monitoring and managing networks. It is one of the most used protocols for this purpose today, since it allows working with products and services by several manufacturers. Nowadays the leading network monitoring solutions provide alerts (SMS, e-mail or Push) to report network infrastructure failures. The most advanced tools already feature visual Dashboards. These boards present critical indicators of network operation through real-time charts. SNMP is the easiest way to access information from different systems to view in monitoring.
This is an application layer protocol (layer seven of the Open System Interconnection – OSI), which normally uses the UDP (User Datagram Protocol) transport protocol port 161. This feature allows abstracting other layers and the management of devices that are outside the source network.
In short, its basic function is to facilitate the exchange of management information among the network devices. To do this, it provides status data for active network elements and important statistics for its operation, such as usage, error rate, flow rate, collision level and others.
The protocol consumes few resources of the network and of the processing, which has led to its dissemination and inclusion even in simple equipment like printers. Among the many items that can be monitored are:
- Charts with traffic statistics;
- Data on toner level in printers;
- Information about CPU usage and memory of various devices;
- Number of processes running on a specific device.
SNMP allows one or more machines in the network to be designated as managers. This device receives information from the other network items, which become agents. By processing this information, it is possible to manage the entire system and easily detect defects.
For this it is common to use the Management Information Base (MIB), a hierarchical tree organized by type of information. In it is recorded all the necessary information for the management of each device using the variables required by the manager.
Each network object, in order to differentiate itself, has a specific identifier (OID, object identifier). The manager must then know the information that can be obtained from the agent so that a query can be made: MIB and OID aid in such task.
The protocol then defines just how the data shall be transmitted since the information collected by the manager machine is stored in the agents themselves. Thus, its architecture consists of a collection of management stations and network elements and SNMP transports the information among them.
Simple and robust
SNMP is simple and robust at the same time, besides being powerful enough and capable of managing even heterogeneous networks. Because the more complex tasks of processing and storing data remain with the manager, the protocol requires little processing and little software.
As it is not directed to connection, that is, it does not require action before or after sending messages, there is no guarantee that the information shall reach its destination. On the other hand, the fact that there is no connection means neither the manager nor the agent needs each other to operate.
The information obtained through the use of SNMP is essential for the network administrator when it comes to defining strategies and making decisions. After all, they are the ones that guarantee that the system operation shall occur without unforeseen situations and with minimal impact on the rest of the operation.
Network monitoring via SNMP
To carry out networks monitoring via network protocol we recommend OpMon, a software that monitors both IT infrastructure and business processes supported by technology. The solution has a specific module for monitoring network traffic, the OpMon Traffic Analyzer. Unlike other solutions, there is no limit to the number of probes.