Building a low cost TCP/IP-based
Wide Area Network in Indonesia

Onno W. Purbo, YC1DAV/VE3

owpurbo@sunee.waterloo.edu
yc1dav@ve3.yc1dav.ampr.org
Department of Electrical and Computer Engineering
University of Waterloo
Waterloo, Ontario
CANADA N2L 3G1
ph: [519] 885-1211 x 2872
FAX: [519] 746-3077

on leave from:
Elctrical Engineering Department and
Inter University Center on Microelectronics
Institute of Technology Bandung
Bandung 40132
INDONESIA

	TCP/IP-based computer network is a de-facto industrial standard in Wide Area computer Network (WAN) to allow various networking tasks, such as remote login, file transfer, e-mail, be done in more efficient manner. In this paper, we report our collaborative efforts involving a number of researchers (mostly from ITB) in Indonesia to adopt and built hardware and software prototypes based on packet radio technology to enable the development of low cost but more efficient TCP/IP-based WAN in developing countries which accommodates the requirements in research as well as manufacturing communities. We are presently building various hardware prototypes, which include low speed (1200 and 4800 bps) packet radio interface on PC based on Intel 8273 High-Level Data link Controller (HDLC) chip, PC-based Terminal Node Controller with one-chip modem Texas Instrument TCM 3105 (1200 bps AFSK modem) and 56Kbps MSK RF-modem at 29MHz for intercity high speed trunk. On software side, we report on our effort in adopting TCP/IP suite on PC which allow us to interconnect Ethernet / Token Ring based wired Local Area Network (LAN) via packet radio WAN as well as to exhange messages between packet radio world to InterNet. Furthermore, at system level, more complex configuration of packet radio stations, which involve several packet radio satellites (PACSAT) currently in operation, have been used to perform experiment in exchanging information between North-America and Indonesia. The use of PACSAT is found to reduce the required time by 75% from the average two days via the conventional HF-forwarder network to about 12 hours or even faster. Having completed some of the prototypes, we believe that packet radio technology will give us an ample hope to built a low cost but efficient TCP/IP-based WAN in Indonesia to serve research, manufacturing industrial and business communities.

why we need to build computer network?
  -	faster exchange of information which serves as a common ground for advancing the technology.
  -	crucial infra-structure to build more efficient environment in advancing the technology in Indonesia, i.e., a bridge between research & development communities and manufacturing communities.

review of the current situation in Indonesia:
  -	PUSILKOM-UI has tried to implement UUCP-based computer network in Indonesia which relies heavily on the expensive long-distance phone links. Furthermore, UUCP uses a fairly simple communication protocols which involves mainly file transfer operations to convey messages from one machine to another and, thus, reach the destination. However, this approach lack of the capabilities, such as network management and automatic routing to accommodate the ever expanding computer network.
  -	Several professional computer-based industries in Indonesia such as USI/IBM and Schlumberger have built their own computer network which connected to InterNet and, thus, allow them to communicate internationally. However, no further attempts has been made by these companies to expand their networking capabilities to allow ordinary users outside their institutions in using their network.
  -	Several national industries, such as, PT. INTI and PT. ELNUSA, are currently working on a low cost approach to built wide area computer network in Indonesia based on 9600 bps packet radio technology running on UHF 440MHz. X.25 link layer protocol is used on top of their 9600 bps physical radio link.
  -	A similar approach has been used in last 5 years by quite a number of amateur radio operators in Indonesia to built their very own wide area packet radio network.