Chapter 6 Administration
NWA1300-NJ User’s Guide
59
SNMP agent functionality, which allows a manager station to manage and monitor
the NWA1300-NJ through the network.
An SNMP managed network consists of two main components: agents and a
manager.
An agent is a management software module that resides in a managed device (the
NWA1300-NJ). An agent translates the local management information from the
managed switch into a form compatible with SNMP. The manager is the console
through which network administrators perform network management functions. It
executes applications that control and monitor managed devices.
The managed devices contain object variables/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/response protocol based on the manager/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.
Table 12
SNMP Commands
COMMAND
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.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
