In our current business economy development schedules are short and project budgets constrained.
When a software project involves the design of Enterprise MIB modules, there is a tried and true approach to reducing associated cost and risk factors. This valuable design approach leverages the practical wisdom and lessons-learned from the development of more than 250 IETF standards-track MIB modules.
The IETF Operations And Management (OAM) Area directorate collected and posted helpful information related to MIB design on the following topics:
- A boilerplate for MIB documents
- Suggested guidelines for MIB security sections
- A list of generic and common textual conventions
- Readily available MIB review and validation tools
These topics and others are published as a “Best Current Practice” in RFC 4181, “Guidelines for MIB Documents”. RFC 4181 describe a better approach towards the design of MIB modules, but does not address the single largest cause of rework and redesign. This critical step, is the creation of an Information Model, as cited by the Network Management Research Group (NMRG).
Within each IETF standards-track MIB module there exists a tacit, de-facto Information Model. This NMRG view describes how Information Models can represent different abstraction levels and provides a set of reverse-engineered Information models for IETF published MIB modules. This NMRG point of view is described in RFC 3444, “On the Difference between Information Models and Data Models”. Since publication of RFC 3444, IETF working groups now define an Information Model before designing their MIB modules.
My consulting clients who choose to first define an Information Model regard this initial step as a great value for reasons that include the following:
- Efficient knowledge transfer from domain subject experts
- Easy to understand graphic format
- Identifies major system components, their relationships and multiplicity
- Effectively specifies the SNMP INDEX for each system component
- Provides a means to express and analysis use cases
And the best value yielded by the small amount of time and effort spent on first defining an Information Model is the significant reduction in latter development stage risk involving re-design of portions of their Enterprise MIB modules.
It is simply easier to identify and correct logic on a single page or screen image than it is to modify definitions and descriptive text across the hundreds of pages comprising a set of enterprise MIB modules. The simple fact that the need for re-design is often first detected during the latter phases of implementing MIB modules in an SNMP Agent or SNMP Manager application serves to compound the value provided by the initial definition of an Information Model.
Certainly the design approach of information modeling before Enterprise MIB design reduces cost and reduces risk that can adversely impact project budget and schedule.
The next step in taking advantage of this valuable design approach is to contact me with your project requirements and questions.