1. Jaringan Telekomunikasi, Sukiswo ST, MT Sukiswo sukiswok@yahoo.com
SNMP MIB Modeling
Sukiswo
Manajemen Jaringan, Sukiswo ST, MT

2. Manajemen Jaringan, Sukiswo ST, MT
Table of Contents
SNMP MIB Object Modeling
Categorize MIB Objects
Translate Model into a MIB
Modeling Example: Car
Manajemen Jaringan, Sukiswo ST, MT 3

3. Manajemen Jaringan, Sukiswo ST, MT
SNMP MIB Modeling
MIB is essential for developing and operating management systems
SNMP MIBs are NOT object-oriented
inheritance is not supported
Analysis of MIB objects is required before writing MIB definitions
Using the designed model, MIB definitions can be easily generated
Similar to software engineering -- must design a system before any implementation!
Manajemen Jaringan, Sukiswo ST, MT 4

4. Step1: Categorize MIB Objects
Components
collections of logical & physical devices or services that are being managed
Attributes
fairly static properties of a modeled object
Actions
control a system
Statistics
useful information about what a system has been doing
State
the current condition of a system
Manajemen Jaringan, Sukiswo ST, MT 4

5. Manajemen Jaringan, Sukiswo ST, MT
Components
physical or logical containment relationships?
what does it contain?
start from the top level and work down until reasonable size is reached
physical containment?
e.g., a list of interface cards
logical containments?
e.g., communication systems
Cardinality
how many of an item are present in a system?
Manajemen Jaringan, Sukiswo ST, MT 4

6. Manajemen Jaringan, Sukiswo ST, MT
Attributes
the fairly static properties of the resource being modeled
e.g., name, id, location, etc.
can be refined into related groups
Identity of an object
determine ID by an attribute
assign an arbitrary ID
Manajemen Jaringan, Sukiswo ST, MT 4

7. Manajemen Jaringan, Sukiswo ST, MT
Actions
SNMP does not support explicit action operation
represented in terms of implicit actions which do their work through side effects
this is achieved by setting some value of a MIB object
Need to define action goals and action steps
action goals?
what does the manager need to be able to do to the managed resource?
action steps?
how does it do it?
Manajemen Jaringan, Sukiswo ST, MT 4

8. Manajemen Jaringan, Sukiswo ST, MT
Statistics
show a picture of the past
a record of the interesting events which occurred since a specific point in time
“high water marks” identify peaks in resource utilization
all stats are considered valid for a specific period of time (known as epoch)
What statistics are we interested in?
Manajemen Jaringan, Sukiswo ST, MT 4

9. Manajemen Jaringan, Sukiswo ST, MT
State
provides insight into the current condition of the resource
represents dynamic properties of the resource
stages of operation
e.g., enabled/disabled
resource usage level
e.g., queue is 50% full
a state graph (e.g., finite state machine) can be used to identify possible inputs and states of the resource
Manajemen Jaringan, Sukiswo ST, MT 4

10. Step2: Translate Model into MIB
Generate an object analysis worksheet containing major components and their cardinality, attributes, statistics and states
Translate the worksheet into MIB syntax
sub-components with a cardinality greater than 0 should be part of a table
stats representing increasing values are Counter type
stats representing high or low water marks are Integer type
states representing discrete stages of operation are enumerated Integer type
states that have fluctuating values are Gauge type
attributes of an object can be
Octet String - human readable descriptions or binary data
Integer - measurable quantities
Manajemen Jaringan, Sukiswo ST, MT 4

11. Modeling Example - Car Physical Containments
Engine compartment
engine
transmission
climate control system
Passenger compartment
seats
dashboard/instrument panel
Chassis
doors
suspension system
Manajemen Jaringan, Sukiswo ST, MT 4

12. Modeling Example - Car Logical Containments
Powertrain
engine
transmission
Exhaust
manifold
muffler
Electrical
spark plugs
battery
Environmental
passenger compartment
climate control
user preferences
Manajemen Jaringan, Sukiswo ST, MT 4

13. Modeling Example - Car Attributes
Engine
horsepower rating
number of cylinders
Powertrain
drive type
2 or 4 wheel
transmission type
manual
automatic
# of speeds
Chassis
fabrication date
Passenger compartment
seat type: bench or bucket
Electrical system
electrical capacity
Climate control system
thermal rating in BTUs
Manajemen Jaringan, Sukiswo ST, MT 4

14. Modeling Example - Car Actions
Powertrain
on/off engine
shift the gear
Exhaust
release smoke
Electrical
use/charge battery
on/off lights
Environmental
on/off heat
on/off air conditioner
change radio channels
Manajemen Jaringan, Sukiswo ST, MT 4

15. Modeling Example - Car Statistics
Engine
peak horsepower
highest RPMs
total RPMs
trip mileage
total mileage
Powertrain
number of upshifts
number of downshifts
Electrical system
peak electrical requirements
average electrical requirements
Manajemen Jaringan, Sukiswo ST, MT 4

16. Modeling Example - Car States
Engine
stopped/starting/running/failed
engine speed in RPMs
oil pressure
fuel consumption rate
Powertrain
drive engaged: 2 or 4
current gear
Chassis
door: open/closed
Electrical system
ok/shorted
battery charge
Climate control system
engaged/off-line
Manajemen Jaringan, Sukiswo ST, MT 4

17. Object Analysis Sheet for Car Engine
Component
Cardinality
Attributes
Statistics
States
Manajemen Jaringan, Sukiswo ST, MT 4

18. Manajemen Jaringan, Sukiswo ST, MT
Engine MO Definition
engCylTable OBJECT-TYPE
SYNTAX SEQUENCE OF EngCylEntry
ACCESS not-accessible
STATUS mandatory
DESCRIPTION “This table represents the sub-components of an
engine that are dependent on the # of cylinders in the engine.”
:: = { engine 1}
engCylEntry OBJECT-TYPE
SYNTAX EngCylEntry
DESCRIPTION “A row in the engine cylinder table. Rows cannot be created or deleted via direct SNMP operations.”
INDEX { engCylIndex }
:: = { engCylTable 1}
Manajemen Jaringan, Sukiswo ST, MT 4

19. Engine MO Definition (cont’d)
EngCylEntry ::= SEQUENCE {
engCylIndex Unsigned32, -- table index
engCylPistonSize Unsigned32, -- attributes
engCylSparkPlugSize Unsigned32,
engCylSparkPlugVendor OBJECT IDENTIFIER,
engCylInjectorCapacity Unsigned32,
engCylFuelConsumed Counter32, -- statistics
engCylSparkPlugState INTEGER, -- states
engCylSparkPlugSparkRate Gauge32,
engCylInjectorState INTEGER,
engCylInjectorFuelRate Gauge32, }
Note that the definition for each object is further required.
Manajemen Jaringan, Sukiswo ST, MT 4

20. Manajemen Jaringan, Sukiswo ST, MT
Summary
Constructing a structure is the most critical part of MIB development
Declaring the actual MIB objects is more of a task of translation than a labor or design
Tools such as DMH MIB Compiler ( and MG-Soft MIB Compiler ( can be used to define and compile SNMP MIB definitions
READING – David Perkins, Understanding SNMP MIBs, Prentice-Hall, Chapter 7
Manajemen Jaringan, Sukiswo ST, MT 4