Ccna certification Practice Tests

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 38.  B.  The management information base, or MIB, is a database of variables in which SNMP 

allows retrieval of information. The attributes in the MIB are the description, variable 

type, and read-write status. Object identifiers (OIDs) are the addressable counters that 

are arranged in a hierarchical fashion. The SNMP agent is the software on the client 

that allows SNMP to collect or pass information. The SNMP community string is used 

to restrict communications to only the clients or servers that have a matching SNMP 

community string.

 39.  B.  The network management station (NMS) is a server to which SNMP is polled back 

or in which SNMP information is trapped. The NMS can escalate problems via email, 

text message, or even visual indicators. Examples of NMS systems are Solarwinds Orion 

and OpenNMS. The syslog is a logging file where system messages are sent. The object 

identifier (OID) is used to describe the SNMP counter being requested. The management 

information base (MIB) is a sort of database of counters that SNMP can use for a specific 

device.

 40.  D.  Trap messages are sent from the network device to the SNMP network management 

station when an event has triggered over a set threshold on the device. An example of an 

event to be trapped is an interface going down or a restriction by port security. The get-

request message is used by an NMS to request information from an SNMP agent. The get-

response message is the message sent back from the client to the NMS after a get-request 

message is received. The set-request message is sent by the NMS to the SNMP client 

requesting a specific writable counter be set to the specified value.

 41.  A.  OIDs are the variables that make up the management information base. Each 

object has a unique ID in a hierarchical format in the form of a tree. As an example, 

1.3.6.1.4.9.2.1.58.0 is the object that holds the router CPU utilization variable. The 

SNMP community string is used to restrict communications to only the clients or servers 

that have a matching SNMP community string. The SNMP agent is the software on the 

client that allows SNMP to collect or pass information. SNMP messages are the data 

relayed with the various SNMP verb commands, for example, get, set, and inform, to 

name a few.

 42.  D.  Inform messages differ from trap messages with respect to acknowledgment. 

Trap messages employ a best effort delivery utilizing UDP. Inform messages employ 

acknowledgments; while they use the User Datagram Protocol (UDP), they rely on the 

Application layer for acknowledgments. Trap messages are not always encrypted and can 

be sent with plain text. Inform messages use acknowledgments at the Application layer. 

Trap messages do not use acknowledgments.

 43.  C.  SNMP version 2c is identical to SNMP version 1 with respect to security. Both 

transmit information in clear text and use the security of community strings to 

authenticate users for access to information. SNMP version 2c does not employ 

encryption. SNMP version 2c does not employ user authentication. SNMP version 2c does 

not employ message integrity.

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