- [Instructor] In managing a sizable network,
Simple Network Management Protocol or SNMP
is a handy thing to have.
SNMP defines mechanisms for implementing various features
needed for maintaining networks,
including securing them.
SNMP specifies the standards
on how to collect network device data.
It also covers the ability
to control network devices remotely.
SNMP implementations allow you
to monitor the health of network devices too.
All these capabilities are necessary
to enhance network security.
SNMP consists of agent,
manager,
management information base,
or MIB,
and managed device.
An agent collects the device data
from an SNMP-managed device.
It receives commands from a manager and executes them.
A manager controls a managed device through an agent.
It obtains data from an agent.
Management Information Base or MIB stores the SNMP data.
A managed device is controlled by an agent.
Therefore, the managed device is an SNMP information source.
Most of the time agents just receive commands
from their managers,
but sometimes they also send messages
back to their managers.
These messages sent back to the managers are called traps.
These are alerts sent by the agents
when there are errors or problems on a managed device.
In summary, you have a managed device in SNMP
such as a server or switch.
Agents sit on top of it.
There's another host on which a manager runs
and the manager talks to the agent
and receives data by using a Get command.
It also controls the agent through a Set command.
An agent sometimes sends messages to its manager
and these messages are called traps.
MIB is a database used by the SNMP manager host.