Muratec F-525, Field Engineering Manual, Page: 80 / 383

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SNMP(Simple Network Management Protocol)
SNMP is a protocol regulated by RFC 1157. It manages the network system activity on TCP/IP.
NGP corresponds to version 1. The latest version is version 3(defined by RFC3411)
SNMP is UDP (User Datagram Protocol).
A SNMP manager software such as WebJetAdmin (HP) can retrieve or rewrite information of a SNMP agent
installed network equipment such as NGP by indicating one or more OID.
The SNMP protocol
The SNMP protocol operates at the application layer (layer 7) of the OSI model. It specified (in version 1) five
core protocol data units (PDUs):
GET REQUEST, is used to request the values of one or more MIB variables.
GETNEXT REQUEST, is used to read the values of variables in the MIB but sequentially. It is often used
to read though a table of values. After a first read with the get-request, get-next-request are used to read
through the remaining rows.
SET REQUEST, is used to update one of the MIB values.
GET RESPONSE, is returned as an answer to a get-request, a get-next-request or set-request message.
TRAP, is used to support significant events (e.g. a cold or a warm restart or a link that has gone down).
GetResponse
GetResponse
GetResponse
GetResponse
SetRequest
SetRequest
TRAP
Pattern 1
Pattern 2
Pattern 3
Manager Agent
Manager Agent
Manager Agent
GetRequest
GetRequest
GetNextRequest
GetNextRequest
Get information of
this object
Set information of
this object
Get information of
the next object
Send response
An event occured