net-mgmt/p5-NSNMP 0.5 MidnightBSD

This is an SNMP message encoding and decoding library, providing very low-level facilities; you pretty much need to read the SNMP RFCs to use it. It is, however, very fast (it's more than an order of magnitude faster than Net::SNMP, and it can send a request and parse a response in only slightly more time than the snmpd from net-snmp takes to parse the request and send a response), and it's relatively complete --- the interface is flexible enough that you can use it to write SNMP management applications, SNMP agents, and test suites for SNMP implementations.

The package also includes NSNMP::Simple, which lets you get or set a single OID via SNMP with a single line of code. It's easier to use, and roughly an order of magnitude faster, than Net::SNMP.