Specifications

SNMP Configuration Summary
5-2 SNMP Configuration
•SNMPnetworkmanagementapplications,suchasEnterasysNetworks’NetSightAtlas,which
communicatewithagentstogetstatisticsandalertsfromthemanageddevices.
SNMPv3
SNMPv3isaninteroperablestandards‐basedprotocolthatprovidessecureaccesstodevicesby
authenticatingandencryptingframesoverthenetwork.Theadvancedsecurityfeaturesprovided
inSNMPv3areasfollows:
– Messageintegrity—Collectsdatasecurelywithoutbeingtamperedwithorcorrupted.
– Authentication—Determinesthe messageisfroma
validsource. 
–Encryption—Scramblesthecontentsofaframetopreventitfrombeingseenbyan
unauthorizedsource.
UnlikeSNMPv1andSNMPv2c,inSNMPv3,theconceptofSNMPagentsandSNMPmanagersno
longerapply.TheseconceptshavebeencombinedintoanSNMPentity.AnSNMPentityconsists
ofanSNMPengineandSNMPapplications.AnSNMPengineconsistsofthefollowingfour
components:
•Dispatcher—Thiscomponentsendsandreceivesmessages.
•Messageprocessingsubsystem—ThiscomponentacceptsoutgoingPDUsfromthe
dispatcherandpreparesthemfortransmissionbywrappingtheminamessageheaderand
returningthem
tothedispatcher.Themessageprocessingsubsystemalsoacceptsincoming
messagesfromthedispatcher,processeseachmessageheader,andreturnstheenclosedPDU
tothedispatcher.
•Securitysubsystem—Thiscomponentauthenticatesandencryptsmessages.
• Accesscontrolsubsystem—Thiscomponentdetermineswhichusersandwhichoperations
areallowedaccessto
managedobjects.
About SNMP Security Models and Levels
AnSNMPsecuritymodelisanauthentica tionstrategythatissetupforauserandthegroupin
whichtheuserresides.Asecuritylevelisthepermittedlevelofsecuritywithinasecuritymodel.
ThethreelevelsofSNMPsecurityare:Noauthenticationrequired(NoAuthNoPriv);
authenticationrequired(AuthNoPriv);and
privacy(authPriv).Acombinationofasecuritymodel
andasecurityleveldetermineswhichsecuritymechanismisemployedwhenhandlinganSNMP
frame.Table 5‐1identifiesthelevelsofSNMPsecurityavailableonSecureStackC3devicesand
authenticationrequiredwithineachmodel.
Table 5-1 SNMP Security Levels
Model Security Level Authentication Encryption How It Works
v1 NoAuthNoPriv Community string None Uses a community string match for
authentication.
v2c NoAuthNoPriv Community string None Uses a community string match for
authentication.