Protocol OverviewNetwork management stations use SNMP to retrieve or alter management data from network elements.A datum of management information is called a managed object; the value of a managed object can be static or variable. Network elementsstore managed objects in a database called a management information base (MIB).MIBs are hierarchically structured and use object identifiers to address managed objects, but managed objects also have a textual namecalled an object descriptor.You can download the latest MIB files from the following path:• https://www.force10networks.com/CSPortal20/Main/SupportMain.aspx.Implementation InformationThe following describes SNMP implementation information.• Dell Networking OS supports SNMP version 1 as defined by RFC 1155, 1157, and 1212, SNMP version 2c as defined by RFC 1901, andSNMP version 3 as defined by RFC 2571.• Dell Networking OS supports up to 16 trap receivers.• Dell Networking OS implementation of the sFlow MIB supports sFlow configuration via SNMP sets.• SNMP traps for the spanning tree protocol (STP) and multiple spanning tree protocol (MSTP) state changes are based on BRIDGEMIB (RFC 1483) for STP and IEEE 802.1 draft ruzin-mstp-mib-02 for MSTP.SNMPv3 Compliance With FIPSSNMPv3 is compliant with the Federal information processing standard (FIPS) cryptography standard. The Advanced Encryption Standard(AES) Cipher Feedback (CFB) 128-bit encryption algorithm is in compliance with RFC 3826. SNMPv3 provides multiple authentication andprivacy options for user configuration. A subset of these options are the FIPS-approved algorithms: HMAC-SHA1-96 for authentication andAES128-CFB for privacy. The other options are not FIPS-approved algorithms because of known security weaknesses. The AES128-CFBprivacy option is supported and is compliant with RFC 3826.The SNMPv3 feature also uses a FIPS-validated cryptographic module for all of its cryptographic operations when the system is configuredwith the fips mode enable command in Global Configuration mode. When the FIPS mode is enabled on the system, SNMPv3operates in a FIPS-compliant manner, and only the FIPS-approved algorithm options are available for SNMPv3 user configuration. Whenthe FIPS mode is disabled on the system, all options are available for SNMPv3 user configuration.The following table describes the authentication and privacy options that can be configured when the FIPS mode is enabled or disabled:Table 89. Authentication and Privacy OptionsFIPS Mode Privacy Options Authentication OptionsDisabled des56 (DES56-CBC)aes128 (AES128-CFB)md5 (HMAC-MD5-96)sha (HMAC-SHA1-96)Enabled aes128 (AES128-CFB) sha (HMAC-SHA1-96)To enable security for SNMP packets transferred between the server and the client, you can use the snmp-server user usernamegroup groupname 3 auth authentication-type auth-password priv aes128 priv-password command to specifythat AES-CFB 128 encryption algorithm needs to be used.Dell(conf)#snmp-server user snmpguy snmpmon 3 auth sha AArt61wq priv aes128 jntRR59aSimple Network Management Protocol (SNMP) 861
