Chapter 32 Access Control
GS1915 Series User’s Guide
271
The managed devices contain object variables or managed objects that define each piece of
information to be collected about a Switch. Examples of variables include number of packets received,
node port status, and so on. A Management Information Base (MIB) is a collection of managed objects.
SNMP allows a manager and agents to communicate for the purpose of accessing these objects.
SNMP itself is a simple request or response protocol based on the manager or agent model. The
manager issues a request and the agent returns responses using the following protocol operations:
SNMP v3 and Security
SNMP v3 enhances security for SNMP management. SNMP managers can be required to authenticate
with agents before conducting SNMP management sessions.
Security can be further enhanced by encrypting the SNMP messages sent from the managers.
Encryption protects the contents of the SNMP messages. When the contents of the SNMP messages are
encrypted, only the intended recipients can read them.
Supported MIBs
A MIB is a collection of managed objects that is organized according to hierarchy. The objects define
the attributes of the managed device, which includes the names, status, access rights, and data types.
Each object can be addressed through an object identifier (OID).
MIBs let administrators collect statistics and monitor status and performance. The Switch uses standard
public (RFC-defined) MIBs for standard functionality.
To view a list of standard MIBs supported by your Switch, see the product datasheet at www.zyxel.com
(
Support
>
Download Library
>
Datasheet
).
To get the private MIBs supported by your Switch, download (and unzip) the correct model MIB from
www.zyxel.com (
Support
>
Download Library
>
MIB File
).
SNMP Traps
The Switch sends traps to an SNMP manager when an event occurs. The following tables outline the
SNMP traps by category.
Table 140 SNMP Commands
LABEL
DESCRIPTION
Get
Allows the manager to retrieve an object variable from the agent.
GetNext
Allows the manager to retrieve the next object variable from a table or list within an agent. In
SNMPv1, when a manager wants to retrieve all elements of a table from an agent, it initiates a
Get operation, followed by a series of GetNext operations.
Set
Allows the manager to set values for object variables within an agent.
Trap
Used by the agent to inform the manager of some events.
