ppt ai3 indonesia activity report 02 1999

(1)

AI3 Indonesia

Activity Report

(2)

Focus

 _{Existing Implemented Infrastructure.}

 _{Experience in Building an AII.}

 _{Low Cost Technology To Educate}

Indonesia.

(3)

Our situation

 _{Develop by University}

 _{Implemented & Run by Education}

Sector



Thanks to AI3, WIDE,

JCSAT without whom all of

these activities never

(4)

Outline

 _{Historical Perspective}

 _{Current Infrastructure.}

 _{Brief overview on our research}

results in:

 _{physical layer.}  _{Network layer.}

(5)

Experience in Internet

building

 January 1993 - Suryono (Texas) install

a packet radio 1200bps to LAPAN.

 _{LAPAN 1200bps to BPPT & Internet}

64Kbps.

 _{286 PC as gateway! to connect the}

whole ITB campus.

 _{Software NOS (running on DOS) as}

(6)

Indonesia Topology Jan.1993

LAN InterNet Universitas Indonesia BPPT LAPAN ITB 1200 bps 2 Meteran

1200 bps UHF

1200 bps UHF LAN InterNet Universitas Indonesia BPPT LAPAN ITB 1200 bps 2 Meteran

1200 bps UHF

Amateur Packet Radio AX.25

at 1200bps

PC Gateway 286!

(7)

ITB in 1995

 _{Telkom Leased Line at 14.4Kbps}  _{RISTI-Telkom to BPPT 64Kbps.}

 _{ITB uses FreeBSD (UNIX) as Router &}

Server.

 _{For the first time ITB sees Web in}

Internet.

 _{ITB learns to build a campus network}

(8)

Typical ITB Campus Net

Backbone Kampus (Thick Ethernet)

LAN LAN

LAN

PC Router

Server (Novell / UNIX) Server Novell / UNIX

PC Router

Internet

Web Server / DNS PC Gateway

Backbone Kampus (Thick Ethernet)

LAN LAN

LAN

PC Router

Server (Novell / UNIX) Server Novell / UNIX

PC Router

Internet

(9)

ITB Today ....

 _{T1 Satelite link to Japan.}

 _{2Mbps link to Indonesia IX.}

 _{VSAT TDMA & SCPC to various universities.}  _{4Mbps Uwave Jakarta-Bandung.}

 _{128 Kbps to Jakarta, Surabaya & Malang.}

 _{WaveLAN 2Mbps for Metropolitan}

(10)

ITB Network Operation

Center

Internet Exchange

Indonesia Exchange Ethernet

To Japan 1.55Mbps 2Mbps

IX Telkom

VSAT TDMA 128/64Kbps

cache cache _router

router Access Server

ITB Network

router

Jakarta - 4Mbps Malang - 128Kbps Surabaya - 128Kbps

(11)

Internet Exchange

Indonesia Exchange Ethernet

To Japan 1.55Mbps 2Mbps

IX Telkom

cache cache _router

ITB Network

router

Terrestrial Network VSAT SCPC 19.2-64K JCSAT-3 Palapa C1 CDMA 2Mbps AX.25 Packet Radio Internet Exchange Indonesia Exchange Ethernet

To Japan 1.55Mbps 2Mbps

IX Telkom

cache cache _router

ITB Network

router

Terrestrial Network VSAT SCPC 19.2-64K JCSAT-3 Palapa C1 CDMA 2Mbps AX.25 Packet Radio Connection to IIX via RadNet

7 Universities via

VSAT TDMA

SCPC

Connect 3 Universities

Connect to 6 Universities

5 Universities / Research Inst

(12)

(13)

AI3 Indonesia

AI3

Indonesia IIX

WIDE

AI3

S-One /

SingaREN vBNS

STARTAP

CA*net3

TransPAC

(14)

Key to Success

Human Resource

Development!

Self-financing!

Community-base

development.

The more people

the lower the cost

Involving students

in the process!

Gives incentives

(15)

National Policy / Activities

 _{AI3 Indonesia has been connecting}

27+ educational institutions to Internet.

 _{AI3 Indonesia is becoming a test bed}

for Indonesia AII.

 _{AI3 Indonesia actives at National NII}

(16)

Results in Physical Layer

 _{Homebrew 2Mbps CDMA.}

 _{VSAT TDMA vs. SCPC Network.}

 Low Cost Access for Schools.

(17)

VSAT TDMA vs. SCPC

 VSAT TDMA 128Kbps Outbound  VSAT TDMA 64Kbps Inbound

 _{VSAT TDMA is not suitable for Internet}

application (especially Web).

 _{Tune TDM for 40 byte (originally}

256byte packet).

(18)

Homebrew 2Mbps CDMA

 Uses Lucent CDMA 2Mbps card

915MHz 250mW.

 _{Run on FreeBSD.}

 _{Homebrew antenna (cost ~US$150).}  Max. distance 15km (use PA for more).  _{Most of our high speed MAN using this}

(19)

(20)

Consequences CDMA 2Mbps

 _{bypassing local line.}

 We promote different alternative for

(21)

Homebrew 64-256Kbps

packet radio

 We are prototyping 64-256Kbps packet

radio network in the lab by

adnan@itb.ac.id.

 _{AX.25 link layer protocol is used.}

 _{GMSK MX 589 one chip modem is used.}

 _{We drive the modem via parallel port.}

 _{MMIC Minicircuit is being build for}

(22)

(23)

(24)

TX & RX Board

(25)

Low Cost Access for Schools

 _{AX.25 1200bps Packet Radio}

Network.

 Proxy Server.

 Dial on Demand for Web &

(26)

SMU /

SMP

Proxy &

Dial on Demand

Radio AX.25

Packet Radio Gateway

AX.25 Network

InterNet

SMU /

SMP

Proxy &

Dial on Demand

Radio AX.25 Packet Radio Gateway

AX.25 Network

InterNet

IntraNet for High Schools

24 hours

Packet Radio

E-mail

(27)

(28)

Soundblaster Modem

 _{PC running Linux}

 _{Software Modem Packet Radio for}

Soundblaster

 Connect SB-10 to Radio

 _{Speed 1200-9600bps.}

 _Check

(29)

Amateur Radio Network

(30)

AMPR.ORG NET

ITB AMPR GATEWAY (LINUX) INTERNET WORLD WIDE AMPR.ORG VHF (Bandung) 1200 bps HF (Nasional) 1200 bps BANDUNG VHF AMPR.ORG YB-NET AMPR.ORG EN (DOS/NOS) JAKUT VHF 1200 bps JAKUT UHF

9600 bps SALATIGA (DOS/NOS) SALATIGA VHF 1200 bps UMM (DOS/NOS) MALANG VHF 1200 bps ITB GATEWAY ELEKTRINDO NUSANTARA UNIV. MUHAMMADIYAH MALANG

(31)

Application Layer

TCP

AMPRNet IP (44.x.x.x)

InterNet IP

Link Layer (AX.25)

(32)

(33)

IPv6 Test Bed

_{Background : The Internet growth caused there is a need for}

new

generation of IP (Internet Protocol)

_{IPv6 Implementation using INRIA Rocquencourt’s IPv6}

Implementation

which based on FreeBSD (2.2.2-RELEASE and 2.2.5-RELEASE)

_{The participants are : ITB, (Institut Teknologi Bandung),}

UNPAR

(Universitas Parahyangan), and UNILA (Universitas Lampung)

_{Next step :}

 Expand IPv6 Network in AI3-Indonesia Network

_{Connect to 6Bone}

(34)

I T B U N P A R

U N I L A

1 6 7 . 2 0 5 . 4 8 . 3 9

1 6 7 . 2 0 5 . 2 2 . 6

1 6 7 . 2 0 5 . 4 8 . 3 5 A n t e n a

B r id g e

A n t e n a

B r id g e W a v e L A N

M o d e m

(35)

Reachability

IPv6 # ping6 5f12:bc00:a7cd:3000:2c0:26ff:feb0:49e5

trying to get source for 5f12:bc00:a7cd:3000:2c0:26ff:feb0:49e5 source should be 5f12:bc00:a7cd:1600:0:ffff:0:1

PING 5f12:bc00:a7cd:3000:2c0:26ff:feb0:49e5

(5f12:bc00:a7cd:3000:2c0:26ff:feb0:49e5): 56 data bytes

64 bytes from 5f12:bc00:a7cd:3000:2c0:26ff:feb0:49e5: icmp6_seq=0 ttl=255 time=4.973 ms

ò^C

(36)

Exotick:

A Single-User Network

Operating System Based

By

(37)

Traditional Kernel Design

 _{Full Hardware Abstraction.}

 _{Centralized Resource Management.}

 _{Protection Mechanism / Multiplexing}

(38)

Hardware Abstraction

 _{Large coverage to make it useful to}

all applications.

 _{Planned to accommodate all}

interfaces from application to hardware resources.

 _{Trapped in vast small details that}

(39)

Impact on Kernel

 _{Large Kernel Size.}

 _{Complex Algorithm.}

 _Unreliable.  _Inflexible.

 _{Hard global optimization since too}

(40)

Impact on Applications

 _Inefficient.

 _{Complex Algorithm.}

 _{Can not grealty improve the}

(41)

Exokernel Prototype Design

 _{Created and introduced by Dawson R.}

Engler and M. Frans Kaashoek from MIT in January 1995.

 _{Main principle is application should}

manage all physical resources.

 _{Exokernel should only manage}

(42)

Exokernel Prototype Design

 _{Use distributed resource}

management.

 _{Exokernel concentrate on}

(43)

Exotick

 _{A single-user network operating}

system based on Exokernel design.

 _{As a start, planned to be a simple}

TCP/IP router.

 Focus on:

 _{Simple operation & programming.}  _{Smaller kernel size.}

(44)

Exotick

 _{Use Assembler language for best}

size and speed fulfillment.

 _{Use Netwide Assembler (NASM)}

(45)

Exotick’s Feature

 _{32-bit OS on Intel’s architecture.}  _{Preemptive multitasking.}

 _{Flat memory model.}  _{Small kernel size.}

(46)

Exotick Project Status

 _{The project has been started since}

August 1998.

 _{The project will be completed by the}

(47)

Results in Network Layer

 _{Network Monitoring by}

ismail@cnrg.itb.ac.id.

 Monitor at http://netmon.itb.ac.id/

 _{Network Map}

(48)

Traffic Distribution Grapher

Describes:

 _{Comparison between Inbound and Outbound}

Traffic

 _{Traffic Distribution by Protocols}

 _{The Most Active Routers/Hosts by Protocols}  _{Daily Usage Trend for some Protocols}

(49)

TDG

Protokol

Host In vs Out

Trend

(50)

Benefits:

 _{Behaviour of the users in ITB (AI3):}

 _{Subjects of interest}

 _{Sites to be visited}

 _{The rush hours}

 _{Most actives computer/host}

(51)

Network Monitoring

(52)

Scotty monitor

Connectivity monitoring

(53)

Scotty monitor

(54)

Web screen http://netmon.itb.ac.id/map.html

Text Map

Timeout alarm

(55)

Web screen

Interface Utility Report

(56)

Results:

 _{Reconfiguration of VSAT TDMA}

interface speed for better performance.

 _{Monitoring the JAMUS (ITB-YWCN) link}

performance.

(57)

Max In:1222.8 kb/s (12.2%) Average In:736.6 kb/s (7.4%) Current In:975.9 kb/s (9.8%) Max Out:1079.3 kb/s (10.8%) Average Out:566.4 kb/s (5.7%) Current Out:650.3 kb/s (6.5%)

(58)

System Platform:

 _{Pentium 100}

 16 MB RAM

 _{2,1 GB Hard disk}

 _{Operating System: FreeBSD}

 _{Main Software: Scotty/Tkined}

(FreeWare) and TCPDUMP.

(59)

Results in Application Layer

 _{Mailing Lists}

 _{English Technical Writting Course}

distance learning test bed.

 Cache & Cache Monitoring.

 _{MPEG-3 Test Bed.}

(60)

Cache

 _{ITB has set several Parents cache.}

 _{Cache person is husni@itb.ac.id}

 We cache all of our Web traffic.

 check out

(61)

HTTP-Cache: What

 _{Use of Proxy Server}

 _{Previously fetched WWW objects are}

stored in Proxy Server

 _{Proxy Server gives cached WWW}

object instead of fetches it from WWW server

(62)

HTTP-Cache: Why

 _{Web is the most popular application}

on The Net

 _{Web traffic in byte is about 40%}

 _{WAN link get congested}

(63)

HTTP-Cache: Facts

(64)

Cache Hierarchy

 _{Cache-Server mesh}

 _{Collaborates using “parent-sibling”}

relationship

 _{Sibling: fetches WWW-object only if it}

is found in local cache

 _{Parent: always fetches requested}

(65)

Cache Hierarchy at ITB

Network

cache-naist1.ai3.net

ns1.itb.ac.id

ns2.itb.ac.id

cache.lib.itb.ac.id cache-en.itb.ac.id

bandung-net

VSAT-net

(66)

Cache Usage Monitoring

 _{Log files}

 _{Daily statistics}

(67)

(68)

(69)

(70)

Results

 _{Over 1.5Gbytes transferred data at a}

normal work-day

 _{Over 400Mbytes transferred data at}

a weekend-day

(71)

Typical Cache Results

 _{Hit requests} _53.90%

 _{Hit bytes} _38.79%

 _{Total requests 406.473}

 _{Total successfull requests} _406.473

 _{Average requests /day} _695.980

 _{Total bytes 582.499.684}

(72)

Mailing Lists

 _{Uses majordomo on FreeBSD}

 _{Run on Dual Pentium 166MHz 32Mb RAM.}  _{More than 220 mailing lists at ITB. (more}

than 75% Indonesian mailing lists).  _{More than 10.000 subscribers.}

(73)

Distance Learning

 _{ITB’s Server:}

http://distance-courses.itb.ac.id/ http://virtual-university.itb.ac.id/

(74)

(75)

(76)

EL-426 Tek-Info

(77)

(78)

(79)

(80)

Test Bed Library Network

 _{Pustakawan@itb.ac.id}

 _{library@itb.ac.id}

(81)

(82)

ITB Cyber Library

 _{Access point:}

 _{Students internet access center.}

 _{1500 users}

 _{Email & web access}

 _{Library on Internet:}

 _{Central Library Home page}

 _{Catalogue search services}

(83)

Build Library Community

 _Librarian:

 _{pustakawan@itb.ac.id}

 _{Subscribe to}_{Majordomo@itb.ac.id}_{, with}

message’s body: subscribe pustakawan

 _Network:

(84)

The ISIS Network ...

Points:

 _{Based on CDS/ISIS}

 _{Sharing CDS/ISIS database}

(85)

Why CDS/ISIS?

 _{Internet based.}

 _{Low cost.}

 _{Easy to deploy.}

 _{Widely used in Indonesia}

 _{Open free system}

 _{can be expanded.}

(86)

CDS/ISIS freeware

 _{Where to get?}

 _{Http://www.unesco.org/}

 _{How to get?}

 _{Internet Web.}

 _{Library automation using CDS/ISIS:}

 _{Developer: IPB Library}

 _{contact: mus@ipb.wasantara.net.id,}

(87)

WAIS-ISIS

 _{ISIS-FreeWAIS:}_{Search Engine for} CDS/ISIS on Internet

 _Feature:

 _{Any CDS/ISIS database}

 _{Networking between WAIS server}

 _{How to get:}

 _{http://www.lib.itb.ac.id/isis/resources.html}

 _Requirement:

(88)

Library Network:

How to join

 _{Contact address}

 _{http://www.lib.itb.ac.id/isis/}  _{ismail@itb.ac.id}

 _{mahmudin@library.itb.ac.id}

 _Requirement?

 _{Need & want to share CDS/ISIS Catalogue data.}

 Services:

(89)

ISIS Hosting

 _{Share CDS/ISIS database}  _{ISIS Hosting at ITB:}

 _{Services: Free and}

Costumized (not free)

 _{http://www.lib.itb.ac.id/isis/}

 _{ITB exchange the Catalogues}

 _{How to join:}

 _{contact: mahmudin@library.itb.ac.id}

(90)

Install Server

 _Requirement:

 _{24 hours internet connection or within intranet}  _{Unix environment}

 _{human resources (operation)}

 _{How to join:}

 _{Share server configuration}  _{Link to other servers}

 _Contact:

(91)

ISIS Network Map

 _{Using WAIS-ISIS and CDS/ISIS files}  _{Servers location:}

 _ITB

 PDII LIPI

 _{Univ. Muhammadiyah Malang}

 _{ISIS Hosting at ITB:}

 _{Institut Pertanian Bogor}  _{Univ. Atmadjaya}

(92)

(93)

(94)

Knowledge Management

 _{KMRG Team}

 _{The project: Build Knowledge sharing tools}

 _{Vision: Build knowledge based communities}

 _{Libraries as knowledgebase}

 _{Mailing list:}

 _{knowledge@hmesvr.ee.itb.ac.id}

(95)

KM Concept

Library as

Knowledgebase

Univ C Univ B

Univ A

Using:

•Email

•Web

(96)

Future Development...

 _{On line transactions}

 _{More database: Catalogues,}

abstracts, papers, etc

 _{Integration with other documents}

format

 _{ISIS Network --> Library Network}

(97)

Java Working Group

 _{Lead by}

team4@students.ee.itb.ac.id, namely: Fira, Raka cs.

 _{Their Page is:}

 _{http://students.ee.itb.ac.id/~team4/lapo}

(98)

Video Conference

 _{25 October 1997: 14:00 Indonesia Time.}

 _{Three Cities: Bandung-Surabaya-Malang}

 _{CU-SeeMe & Its Reflector.}

 _{Aiming for high school network in}

Indonesia.

 _{July 1997: Panel Discussion on the}

(99)

Video on Demand

 _{Supported by Microsoft & Progressive}

Network Tools.

 _{Splitter for UNFCC COP3 December}

1997.

 _{Publisher for “ITB’s Alumny}

(100)

AI3 Indonesia Member

Activities

 _{YWCN Malang, Surabaya, Denpasar.}

 _{UNPAR (University of Parahyangan}

Bandung)

(101)

(102)

Vision :

Making the

knowledge more accesible

Mission :

building the most efficient way the

information network for education

(103)

Mission implementation

:

. Regional Network Distribution Center for

AI3-Indonesia in East Java, Bali and Jakarta

. Junction for the education and research computer network within the all area of our operation

. Internet socialization for education and research community

(104)

Socialization program

(encouraging demand of

(encouraging demand of

the Internet for education)

 _{Scientific seminar}

 _{Guest lecturing}

 _{Internet Education panel discussion}

 Study group > 30 active members

 _{Technology exhibition}

 Internet Talk show programme

(105)

(106)

(107)

Provide Access and

Cooperative Network

Development (1)

 _{Dedicated connection :}

. 8 education institution ( > 2000 users)  _{Non dedicated connection (dial up lines ):} . Lecturers : 120

Teachers : 75

(108)

Provide Access and

Cooperative Network

Development (2)

 _{Faculty of Economics University Brawijaya -}

Malang

 _{FTI - ITS - Surabaya}

 _{The State University of Malang (in progress)}

 _{STIE Malang Kucecwara}

 _{University of Bhayangkara - Surabaya}  _{St.Albertus High School - Malang}

 _{WISH/BTC - Malang}

 _{University of Muhammadiyah Malang}

(109)

Provide Access and

Cooperative Network

Development (3)

 _{Hosting for the information contents}

of education and research institutes : - www and mailing list

 _{Joint forces for internet education}

(110)

Equipment

 _{18 x PC based server}

 _{2 x Fast Ethernet 10/100 mbps hub}

 _{2 x Access Server Telematic}

 _{Total Storage Capacity = 100}

GigaByte

 _{6 x Cisco Router}

(111)

Bandwidth

 _{Surabaya/Malang - AI3 Indonesia}

Gateway (ITB Bandung) = 256 kbps

 _{Surabaya/Malang - Indosat (backup}

link)

(112)

Applied Research

Activities

 _{Wireless Network}

 Internet application for education  _{Network operating system}

integration

(113)

Wireless MAN Test for

Low Cost Video Conferencing Oct ‘97 (1)

Link to :

Malang Metropolitan Area Network (using 2 mbps wireless CDMA) . YWCN Malang NOC

. St. Albertus High School

. FM 102 Broadcasting Station (radio live broadcasting)

---Surabaya Metropolitan Area Network (using 2 mbps wireless

CDMA)

. YWCN Surabaya NOC

. Campus of FTI-ITS Surabaya

---Bandung (AI3-ITB) Indonesia gateway

(114)

Wireless MAN Test for

Low Cost Video Conferencing Oct ‘97 (2)

Installed equipment for test :

+ Karlbridge router for Wireless CDMA 2 mbps located at : . YWCN Malang NOC (local center hub)

. YWCN Surabaya NOC (local center hub)

. St. Albertus High School Malang (venue of video conference)

. FM 102 Radio Station (radio live broadcasting) . FTI-ITS Surabaya (venue of video conference) . AI3-ITB Bandung (venue of video conference)

+ CuSeeMe Reflector at AI3-ITB Bandung

(115)

(116)

Wireless MAN Test for

Low Cost Real Audio Broadcasting Dec ‘97

We’re doing this test during Panel Discussion of Malang Internet Academic Network

+ The panel discussion was broadcasting live

simultanously to the Internet (video and audio) and to the FM radio band (audio only)

Installed equipment on this test :

. STIE Malang Kucecwara (venue)

. FM 102 Radio Station (radio live broadcasting)

(117)

Wireless MAN Test for

Low Cost Real Audio Broadcasting (2)

. STIE Malang Kucecwara (venue)

. FM 102 Radio Station (radio live broadcasting)

+ Real Audio Encoder & Server located at STIE Malang Kucecwara (venue)

Archive (indonesian) of this panel discussion can be reached at :

(118)

(119)

Wireless MAN Test for

Low Cost Real Audio Broadcasting

during AI3 Indonesia 1st Annual Meeting Surabaya - June 1998

+ Karlbridge router for Wireless CDMA 2 mbps located at : . Venue in Widya Mandala University campus - Surabaya . YWCN Surabaya NOC

(120)

(121)

Research

-Currently work in progress

Building Electronic Commerce

. Collaboration with some universities and private sector

. Collaboration with Internet and Computer Network Study Group

Combining Internet/Online Marketing and International Marketing

. Collaboration with Internet and Computer Network Study Group . http://www,ywcn.or.id/inmark/

Using various low power Wireless CDMA for long distance carrier

Bandwidth optimization and

(122)

(123)

University of Lampung’s Website

BBS Unilanet

University of Lampung *Library and Research Information Exchange

*Increasing human resources qualification

*Ready to be AI3 gateway for

(124)

Unila’s Website:

offers us about:

 _{General Information}

of University of Lampung

 _{Journals and}

Research Report from some faculties and department

 _{Institutions in Unila}

and their purposes

 _{Students’ Activities}

Information

 _{Other Activities about}

science and

technology, nature conservation, and hobbies

 Relationship and

cooperation with other universities in

(125)

Some Journals online

pages::

 _{Journal of Agrotropika}

- contains of analysis and research in agronomy

 Journal of Social and Agricultural Economics

- about social and agricultural

(126)

pages ::

 _{Journal of Komunitas}

- concern about social politics

and cultural issues.

 _{Journal of Tropical Soils}

(127)

 Journal of Science and Technology

- all about research reports of math,

natural science, and

technological implementations

(128)

Interests:

 _{Wetlands International Indonesia}

Program

- It is a part of a global organization which the mission is “To sustain and restore wetlands, their resources and bio-diversity for future generations through research, information exchange, and conservation activities”

 Kite Aerial Photography

(129)

University of Lampung in a Search Engine:

 _{University of Lampung}

(130)

(131)

(132)

UNPAR

 _{176 student users (}_{http://student.}

unpar.ac.id/cgi-bin/userlist)

 ₃₄₈ _university _staff _users ₍

http://home.unpar.ac.id/cgi-bin/

(133)

UNPAR Traffic

 _{From our statistics with SNMP in our}

router (maingtw) showing number of data go out greater than data go in (

(134)

UNPAR Activities

 _Developing _software _from _public

sources (free software).

 _{User Training}

 _{Searching information for research.}

 _{Mailing List / Discussions Platform}

 _{UNPAR Web at (}_{http://www.unpar.ac.id/}₎

(135)

Summary

 _{ITB has managed to integrate 20+}

educational institutions to Internet.

 Major IT used:

 _{2Mbps CDMA Network.}

 _{Web based distance learning.}

 _{Real Publisher / Microsoft NetShow.}

 Key to success:

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References

 _{http://ai3.itb.ac.id/}

 _{http://xxx.itb.ac.id/~yc1dav/}

 _{http://xxx.itb.ac.id/~cnrg/}

 _{http://xxx.itb.ac.id/~adnan/}

 _{http://distance-courses.itb.ac.id/}

 _{http://virtual-university.itb.ac.id/}

 _{http://netmon.itb.ac.id/}

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