Matakuliah
Tahun
Versi
: H0372/Manajemen Jaringan
: 2005
: 1/0
Pertemuan 05
Model Informasi - SMI
1
Learning Outcomes
Pada akhir pertemuan ini, diharapkan mahasiswa
akan mampu :
• Menjelaskan model Information management
2
Outline Materi
• SMI
• ASN.1
3
Information Model
• Structure of Management Information
(SMI)-RFC1155
• Managed Object
• Scalar
• Aggregate or tabular object
• Management Information Base (RFC 1213)
4
SMI
• Structure of Management Information
• SMI defines for a managed object
• Syntax
• Semantics
• Additional information such as status
• Example
sysDescr
Syntax
Definition
Access
Status
: { system 1 }
: OCTET STRING
: "A textual description of the entity "
: read-only
: mandatory
5
Managed Object
• Managed objects can be
• Network elements (hardware, system)
• Hubs, Bridges, Routers, Transmission facilities
• Software (non-physical)
• Programs, Algorithms
• Administrative information
• Contact person, Name of group of objects
(IP group)
6
OSI Managed Object
• Scalar object in Internet vs Object-oriented approach
in OSI
• OSI characteristics of operations, behaviour, and
notification are part of communication model in
Internet: get/set and response/alarm
• Internet syntax is absorbed as part of OSI attributes
• Internet access is part of OSI security model
• Internet status is part of OSI conformance
application
• OSI permits creation and deletion of objects; Internet
does not: Enhancement in SNMPv2
7
Managed Object
Object
Object
Type
Name:
OBJECT
IDENTIFIER
Syntax:
ASN.1
Object
Instance
Encoding:
BER
8
Abstract Syntax Notation One
• ASN.1 is more than a syntax; it’s a language
• Addresses both syntax and semantics
• Two type of syntax
• Abstract syntax: set of rules that specify
data type and structure for information storage
• Transfer syntax: set of rules for communicating
information between systems
• Makes application layer protocols
independent of lower layer protocols
• Can generate machine-readable code: Basic
Encoding Rules (BER) is used in management
modules
9
Management Information Tree
itu
0
• iso
International Standards Organization
itu I
nternational Telecommunications Union
dod
Department of Defense
• Designation:
• iso
1
• org
1.3
• dod
1.3.6
• internet 1.3.6.1
iso
1
iso-itu
2
org
3
dod
6
internet
1
OSI Management Information Tree
10
Internet Subnodes
Internet
{1 3 6 1}
directory
(1)
directory
mgmt
experimental
private
mgmt
(2)
experimental
(3)
private
(4)
OBJECT IDENTIFIER ::= {internet 1}
OBJECT IDENTIFIER ::= {internet 2}
OBJECT IDENTIFIER ::= {internet 3}
OBJECT IDENTIFIER ::= {internet 4}
11
Object Name
itu
0
iso
1
iso-itu
2
org
3
dod
6
• internet OBJECT IDENTIFIER ::=
{ISO(1) ORG(3) DOD(6) INTERNET(1)}
internet
1
private
4
enterprise
1
IBM
2
12
SNMP Data Type
SNMP ASN.1
Data Type
Tag
Structure
Number
Class
Simple or
Primitive
Defined or
Application
Contructor or
Structured
Universal
Application
Contextspecific
Private
13