RAD Data comm IPmux-11 Manuel D’Utilisation

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Appendix C  SNMP Management 
Installation and Operation Manual 
C-4 
SNMP Environment 
IPmux-11 Ver. 2.00 
SNMP Communities 
SNMP delimits management domains by defining communities. Each community 
is identified by a name, which is an alphanumeric string of up to 255 characters 
defined by the user.  
The IPmux-11 SNMP agent defines strings of up to 10 characters (case sensitive, 
numeric and alphabetical). 
Any SNMP entity (both managed entities and management stations) is assigned a 
community name by its user. In parallel, the user defines a list of the communities 
for each SNMP entity that are authorized to communicate with the entity, 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. 
Authentication 
In accordance with SNMP protocol, the SNMP community of the originating entity 
is sent in each message.  
When an SNMP message is received by the addressed entity, it first 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 previously explained. Thus, a setRequest for 
a 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.  
Network Management Stations 
The IPmux-11 SNMP agent stores the IP address of the Network Management 
Station (NMS) that is intended to manage it.