Realization of a TMN Java Management API

2000. 5. 10

발표자

:
통신시스템연구실

최재원

jwchoi@cdcs.changwon.ac.kr

Network Operations and Management Symposium ‘98 (p.412 ~ p.421)

Christian Hubert (Hubert@ese
-
metz.fr)

Birgit Frohnhoff (Frohnhoff@tzd.telekom.de)

Gerd Aschemann (Aschemann@Informatik.TU
-
Darmstadt.de)

Realization of a TMN Java Management API

2



Introduction



General Requirements for a TMN
-
Platform



Concepts for the Implementation of a Java API



Comparison of the Java API with other APIs



Inheritance Tree for the Java
-
ASN.1 classes



Representation of an ASN.1
-
Value in Java
-
ASN.1



Example for the usage of the Java
-
ASN.1 class “SEQUENCE”



Encoding of ASN.1 values with Java
-
ASN.1



Integration in an existing TMN
-
Environment



Customer Network Management scenario



Conclusion

Contents

3



Java language

•

is similar to the well
-
known C++ language

•

excludes concepts like pointers and manually memory management



Java
-
ASN.1 API

•

a novel approach which realizes the objet oriented representation of ASN.1


values completely in Java

•

the main difference of existing C++ wrapper classes : does not encapsulate


existing native C code

•

ASN.1 value representations without referencing the corresponding type


definitions (metadata) during runtime

Introduction

4

General Requirements for a TMN
-
Platform

5



Java

•

an optimal solution for small applications

•

feasible to perform non time critical operations on a separate machine

•

well suited for the realization of an application for customer network management



Communication Services

•

the most specific and important component for TMN platform

•

via Q3 or X
-
interfaces that conform to Open Systems Interconnection(OSI)



Abstract Syntax Notation One (ASN.1)

•

values described in ASN.1 have to be exchanged between management applications


based on OSI conformance

☞

further enhancements of the Java libraries are required

General Requirements for a TMN
-
Platform (cont’d)

6

Concepts for the Implementation of a Java API

7



Java Wrapper Class

•

native method (Java method) call

•

one has to take care of availability and security



Pure Java API

•

in order to avoid the restriction of native methods

•

the new Java “Swing”
-
library and automatic translation tools

•

the need to integrate Java with these protocols and the required processing power



Java Client Application

•

most of the operations will be performed in the Java environment

•

only for some complex methods native routines will be called on the server

☞

the realization of Java
-
ASN.1 API is mainly based on a the client/server model

Concepts for the Implementation of a Java API (cont’d)

8

Comparison of the Java API with other APIs

9



XOM

•

the terms “object”, “package”, and “attributed” are extensively used

•

implemented in ANSI.C
☞

complex manual pointer handling



ASN.1++ (and AIDA)

•

every XOM structure is encapsulated by the objects of the C++ wrapper classes

•

a basic understanding of XOM is still require



Java
-
ASN.1

•

pure Java and client/server approach are used for the prototype implementation



Encoding and Decoding of ASN.1 values

•

every ASN.1 API requires a database with the ASN.1 type(metadata) information

•

give an optional access to the required metadata information

Comparison of the Java API with other APIs (cont’d)

10

Inheritance Tree for the Java
-
ASN.1 classes

11



G
eneric Superclass

•

represents common functionalities of ASN.1 data types
-

like encoding and decoding

•

a lot of virtual methods are defined in this generic superclass, which can be


specialized individually for each type in the common classes



Common Classes

•

each ASN.1 type is represented by common Java object class

•

complex representation of values is realized by encapsulating contained elements

•

all required functionalities dealing with an ASN.1 value representation can be


invoked directly via methods which are defined in the corresponding common class



Optional Individual Classes

•

individual objet classes might be generated for each module specific ASN.1 type

•

the common class functionality will be enhanced with individual convenience


methods

Inheritance Tree for the Java
-
ASN.1 classes (cont’d)

12

Representation of an ASN.1
-
Value in Java
-
ASN.1

13



R
epresentation

•

each instance of an individual class does contain a mandatory type descriptor object,


which stores additional information about the ASN.1 type definition



Two Different Approaches

•

by accessing the contained type descriptor object

－

informationless approach
, if a null pointer will be returned


no additional type information will be required

－

optional metadata approach


type information is available during runtime

☞

type specific information has to be coded in the application anyway

•

the metadata approach is only an optional feature

•

if the metadata approach is supported by an Java
-
ASN.1 API, it has to be provided in


parallel to the informationless approach

Representation of an ASN.1
-
Value in Java
-
ASN.1 (cont’d)

14

Example for the usage of the Java
-
ASN.1 class “SEQUENCE”

M
Y
E
XAMPLE

::= SEQUENCE {


I

INTEGER,


G

G
RAPHIC
S
TRING
,


S

SET OF INTEGER }

15



Java
-
ASN.1 classes

•

Java type V
ECTOR

which is used for the contained object
VALUE

•

this class is able to store one or more classes in any order



Keyword “optional”

•

an omitted optional component should not be represented via a Java null reference

•

the member
PRESENT

was defined

－

TURE : this element represents a present optional type or even a mandatory component

－

FALSE : an optional component has been omitted

☞

an object could be temporary set to “non present” without deleting its internal


value representation

Example for the usage of the Java
-
ASN.1 class “SEQUENCE” (cont’d)

16

Encoding of ASN.1 values with Java
-
ASN.1

17



ASN.1 type information

•

split up the representation and the encoding of an ASN.1 value two separate


functional components in order to omit the type information partially

－

ASN.1
-
client


all kinds of value representations well be handled by Java objects

－

ASN.1
-
server


the functional component is responsible for encoding the ASN.1 values

•

this client/server approach does support migration of existing TMN APIs into Java

•

type information has to be transmitted between the ASN.1
-
client and ASN.1
-
server

•

type individual class will simply contain a unique identifier that can be transmitted


together with its value between client and server

Encoding of ASN.1 values with Java
-
ASN.1 (cont’d)

18

Integration in an existing TMN
-
Environment

19



ASN.1 Interchange Format (AIF)

•

in order to provide translation of the values between client and server

•

no type reference required

•

can be integrated into an existing ASN.1 API with only a few additional lines of code

•

remote method invocation (RMI) or object serialization might be applied



AIF adaptation

•

Common Management Information Service (CMIS) interface is completely based on


a ASN.1 definition


easy

•

the platform client is programmed in pure Java and does not contain any native code

•

the server part is implemented in a vendor specific manner

Integration in an existing TMN
-
Environment (cont’d)

20

Customer Network Management scenario

21



Customer Network Management (CNM)

•

by using Java in conjunction with the proposed Java
-
ASN.1 API a network provider


will be able to offer functionally more complex CNM applications to the customer


without the necessity of any investment in platforms on the customer side

•

the network provider is able to integrate a CNM
-
application into the standard


management platform due to the usage of CMIP

•

the customer will be able to send TMN conform protocol data units to the network


provider without the requirement of maintaining a full seven layer OSI stack itself

•

all software that the customer will need can be downloaded from an Internet server

•

the exchange of a management information will be done with aid of AIF which will


be transmitted over TCP/IP

Customer Network Management scenario (cont’d)

22



Conclusion

•

Java
-
ASN.1 API

•

client/server approach




Future Work

•

evaluating the new Java
-
ASN.1 API by a prototype application in the area of


customer network management

Conclusion