NET-SNMP is a free open source SNMP package that is based on the earlier UCD-SNMP and CMU-SNMP packages developed at University of California at Davis and Carnegie Mellon University, respectively. The current version supports SNMP Versions 1, 2c, and 3. It is available for both Windows and Unix platforms.
This package includes a complete suite of SNMP programs. It includes SNMP agent and server software, as well as the command-line utilities for interacting with SNMP devices to extract information or change settings that we used in our scripts. In fact, we used only a small subset of the NET-SNMP suite of applications in this book.
We wrote and tested all of the scripts in this book using NET-SNMP Version 4.2.
The official NET-SNMP web page is http://www.net-snmp.org/, which is mirrored at http://net-snmp.sourceforge.net/. This site contains documentation and other useful information about the package. You can download the software via FTP from ftp://ftp.net-snmp.org/pub/sourceforge/net-snmp/.
Unfortunately, we are not aware of any books written specifically about NET-SNMP. However, Essential SNMP by Douglas Mauro and Kevin Schmidt (O'Reilly), does a good job of covering SNMP in general, and includes some discussion of NET-SNMP as well.