RAD Data comm Modular Access Device with Integrated Router Manuel D’Utilisation

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Appendix C  SNMP Management 
FCD-IPM Installation and Operation Manual 
C-4 SNMP 
Environment 
 
with it, and the access rights associated with each community (this is the SNMP 
community name table of the entity). 
In general, SNMP agents support two types of access rights: 
•  Read-only  the SNMP agent accepts and processes only SNMP getRequest 
and getNextRequest commands from management stations which have a 
read-only community name. 
•  Read-write  the SNMP agent accepts and processes all the SNMP commands 
received from a management station with a read-write community name. 
SNMP agents are usually configured to send traps to management stations 
having read-write communities. 
Authentication 
In accordance with the SNMP protocol, the SNMP community of the originating 
entity is sent in each message. 
When an SNMP message is received by the addressed entity, first it checks the 
originator's community: messages with community names not included in the 
SNMP community names table of the recipient are discarded (SNMP agents of 
managed entities usually report this event by means of an authentication failure 
trap). 
The SNMP agents of managed entities evaluate messages originated by 
communities appearing in the agent's SNMP Community Names table in 
accordance with the access rights, as explained above. Thus a setRequest for an 
MIB object with read-write access rights will nevertheless be rejected if it comes 
from a management station whose community has read-only rights with respect to 
that particular agent.