NMIS supports using SNMPv3 for securing the collection of sensitive network information. This is especially important from core switches and routers which if compromised could have a considerable business impact. This configuration note does not include details about the SNMPv3 protocol, and assumes that people are wanting to use the authPriv (Authentication and Privilege) mode which is the most secure.
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| NMIS9 name | Name | OID | Notes |
|---|---|---|---|
| des | usmDESPrivProtocol | 1.3.6.1.6.3.10.1.2.1 | RFC3411 |
| 3des | usm3DESPrivProtocol | 1.3.6.1.4.1.14832.1 | RFC3411 |
| aes (or aes128) | usmAESCfb128PrivProtocol | 1.3.6.1.4.1.14832.2 | Blumenthal implementation of SNMPv3 |
| aes192 | usmAESCfb192PrivProtocol | 1.3.6.1.4.1.14832.3 | Blumenthal implementation of SNMPv3 |
| aes256 | usmAESCfb256PrivProtocol | 1.3.6.1.4.1.14832.4 | Blumenthal implementation of SNMPv3 |
| aes192c | cusmAESCfb192PrivProtocol | 1.3.6.1.4.1.9.12.6.1.1 | Cisco implementation of SNMPv3 AES192 |
| aes256c | cusmAESCfb256PrivProtocol | 1.3.6.1.4.1.9.12.6.1.2 | Cisco implementation of SNMPv3 AES256 |
| aes192c2 | usmAES192Cisco2PrivProtocol | 1.3.6.1.4.1.9.12.6.1.101 | A mysterious version 2 of the Cisco implementation, possibly related to pysnmp |
| aes256c2 | usmAES256Cisco2PrivProtocol | 1.3.6.1.4.1.9.12.6.1.102 | A mysterious version 2 of the Cisco implementation, possibly related to pysnmp |
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Many Cisco devices will support SHA256 but only AES128 (which given the entropy is reasonable "AES-128 would take about 2.61*10^12 years to crack" https://www.ubiqsecurity.com/128bit-or-256bit-encryption-which-to-use/).
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This is by no means a comprehensive list of the products we support.
| Vendor / Operating System | SHA | AES |
|---|
| NMIS Considerations | |
|---|---|
| Cisco IOS | SHA1 |
| AES256 | "aes256c" needs to be configured as the entry.configuration.privprotocol" value in NMIS |
| SHA1 |
| AES192 | "aes192c" needs to be configured as the entry.configuration.privprotocol" value in NMIS | ||
| SHA1 | AES128 | ||
| Cisco NX-OS | SHA1 | AES128 | |
| SHA256 | AES128 | ||
| Fortinet | SHA256C | AES256C | "sha256" needs to be configured as the entry.configuration.authprotocol" value in NMIS AND "aes256c" needs to be configured as the entry.configuration.privprotocol" value in NMIS |
| Palo Alto | SHA1 | AES128 | |
| SHA224 | AES128 | ||
| SHA256 | AES128 | ||
| SHA384 | AES128 | ||
| SHA224 | AES192 | "aes192c" needs to be configured as the entry.configuration.privprotocol" value in NMIS | |
| SHA256 | AES192 | "aes192c" needs to be configured as the entry.configuration.privprotocol" value in NMIS | |
| SHA256 | AES256 | "aes256c" needs to be configured as the entry.configuration.privprotocol" value in NMIS | |
| SHA384 | AES192 | "aes192c" needs to be configured as the entry.configuration.privprotocol" value in NMIS | |
| SHA384 | AES256 | "aes256c" needs to be configured as the entry.configuration.privprotocol" value in NMIS |
You may notice that when configuring SNMPv3 on a (for example) Cisco IOS device that there is not an explicit AES192C/AES256C in the command, rather it is needed to be defined as AES 192 and/or AES 256.
When configuring the device for NMIS, you will need to explicitly tell it to use AES192C/AES256C using node_admin.pl (example covered previously).
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