Using the building blocks of SMI, objects are defined and given a place as nodes in the object tree. The object tree groups logically related objects together under a subtree. Such a subtree is called a Management Information Base (MIB). Each MIB (except for vendor-specific MIBs under the enterprises portion of the OID tree) has to be registered with an administrative authority, which in turn, assigns a unique OID to the root of the MIB subtree.
An example of a MIB is the Internet TCP/IP MIB, commonly referred to as MIB-II. It includes objects that are associated with TCP/IP variables and SNMP protocol variables. Other MIBs are defined for OSI protocols, Gateway protocols, and other protocols.
UnixWare 7 supports the standard objects in the following MIBs that are readable and writable. In other words, all writable objects listed can be set and all readable objects can be retrieved using SCO SNMP.
UnixWare supports the readable objects in the following MIBs that can be retrieved with SCO SNMP (none of the writable objects can be set).
UnixWare also supports all the objects under the SNMP Multiplexing (SMUX) group.
SCO PPP in UnixWare 7 does not support the following MIBs:
Each MIB is divided into logically related groups of objects. The important ones are: system, interfaces, tcp, udp, ip, egp, icmp, and snmp. These are also the groups under MIB-II. SCO SNMP supports MIB-II and can therefore manage all MIB-II objects.
Each object in the MIB has two important characteristics: its object identifier (OID) and its type. Object types are constructed from the fundamental types defined in the SMI.
The system group contains general information about the network node. An example of this is the physical location of the node, for example, ``R&D Facility, 3rd floor machine room.''
The interfaces group contains information about network interfaces, such as Ethernet® and point-to-point links. Information is kept about such items as interface status (for example, up or down), packet counts, and so on.
The rest of the groups contain information about the particular protocol to which they refer. This includes items such as the number of packets received with a particular protocol type and the number of packets received with incorrect checksums.