SNMP describes the hierarchal storage of management objects (referred to with object IDs or OIDs) with Management Information Base (MIB) files. The Microchip SNMP server demo includes two MIB files:
• mchip.mib - This is an Abstract Syntax Notation One (ASN.1) formatted MIB file containing information about the variables used in the demo.
• snmp.mib - This is a custom-formatted file that can be parsed to create webpage and header resources that can be accessed with a PIC microcontroller.
The TCP/IP stack includes the mib2bib utility, which will compile the custom Microchip MIB script (snmp.mib) to generate two files called snmp.bib and mib.h. The snmp.bib file is a compressed record of management objects that will be stored with web pages and the mib.h file contains C defines for each OID. These files are included in the appropriate directories for the TCP/IP Demo Apps, but for a custom application you must copy snmp.bib to your web page directory, copy mib.h to your application directory and include it in your project, rebuild your project, and then rebuild and re-upload your web page. This will bundle the BIB file into your web page image, which will allow the SNMP agent to search for the required variable information with the MPFS file system.