SNMP Protocol

In this tutorial, we will be covering the SNMP at Application Layer in detail.

• SNMP mainly stands for Simple Network Management protocol.

• It is basically a framework that is used for managing the devices on the internet by using the TCP/IP protocol suite.

• Basically, SNMP provides a set of fundamental operations in order to monitor and maintain the Internet.

• It is an application layer protocol that was defined by the Internet engineering task force.

• This protocol is mainly used to monitor the network, detect the faults in the Network, and sometimes it is also used to configure the remote devices.

Concept of SNMP

The SNMP protocol makes the use of Manager and Agent; where the manager is usually a host that controls and monitors the set of agents.

• The SNMP is an application-level protocol and it consists of a few manager stations that mainly controls a set of agents. This protocol is mainly designed at the application level so that it can monitor the devices that are mainly made by different manufacturers and that are installed on different physical networks.

Thus there are three components in the architecture of the SNMP:

• SNMP Manager

• SNMP Agent

• Management Information Base

SNMP Manager

It is basically a centralized system and it is mainly used to monitor and manage devices that are connected with the network.SNMP manager is typically a computer and it is used to run one or more network management systems.

Given below are the main functions of SNMP Manager:

1. Collects response from the agents.

2. To acknowledge asynchronous events from the agents.

3. To set variables in the agent.

4. Queries the Agent

SNMP Agent

SNMP Agent is basically a software program that is packaged within the network element. It is mainly installed on a managed device where managed devices can be switches, servers, routers, PC, etc.

Mainly the agents keep the information in the database also the manager has the access to the values present in the database.

Given below are the main responsibilities of the SNMP Agent:

• SNMP agents mainly collect the management information about its local environment

• The SNMP agent mainly signals an event to the manager.

• The SNMP agents also act as a proxy for some non–SNMP manageable network nodes.

Thus the management with SNMP is mainly based on these given ideas:

1. An SNMP manager checks the agent by requesting information that mainly reflects the behavior of the SNMP agent.

2. The SNMP manager also forces the agent to perform the task by resetting the values in the database of the agent.

3.Management process is also contributed by the agent just by warning the SNMP manager about an unusual situation.

Management Components

In order to perform the Management tasks, the SNMP protocol makes the use of two other protocols and are SMI and MIB. We can also say that the Management on the Internet is done by the cooperation of three protocols and these are SNMP, MIB, SMI.

Let us discuss their roles one by one;

Role of SNMP

The SNMP protocol performs some specific roles in Network Management;

• It mainly defines the format of the packet that needs to be sent from the manager to the agent or vice-versa.

• SNMP is also used to interpret the result and create the statistics.

• The packets that are exchanged between the manager and agent contains the name of the object(variable) and their status(values).

• The SNMP is also responsible for reading and changing these values.

Role of SMI

In order to use the SNMP, there is a need for some rules and these rules are for naming the objects. Now its time to take a look at the roles of SMI:

• SMI(Structure of Management Information) is mainly used to define the general rules for naming the objects.

• It is also used to define the type of objects that includes( range and length).

• This is also used to show how to encode the objects and values.

• The SMI does not define the number of objects that should be managed by an entity.

• It also does not define the association between the objects and their values.

Role of MIB

In order to manage each entity, this protocol is mainly used to define the number of objects and then to name them according to the rules defined by the SMI and after that associate a type to each named object.

• MIB( Management Information Base) is mainly used to create a set of objects that are defined for each entity that is similar to the database.

• Thus MIB mainly creates a collection of named objects, their types.

Advantages of SNMP Protocol

Given below are some of the benefits of using SNMP :

1. It is the standard network management protocol.

2. This protocol is independent of the operating system and programming language.

3. The functional design of this protocol is Portable.

4. The SNMP is basically a core set of operations and it remains the same on all managed devices. Thus SNMP supports extendibility.

5. SNMP is a universally accepted protocol.

6. It is a lightweight protocol.

7. This protocol allows distributed management access.

Disadvantages

Some of the drawbacks of SNMP are as follows:

• This protocol leads to the reduction of the bandwidth of the network.

• Access control, authentication, and privacy of data are some largest security issues using this.

• SNMP deals with information that is neither detailed nor enough well organized.