Telecommunication failures rectified
By Reiner Simanjuntak
SINGAPORE (JP): New telecommunications technology has offered telecom carriers a cheaper and more resilient way to increase their network capacity in transmitting voice and data signals, to meet the rising demand on telecom services like Internet, tele- banking and other multimedia applications.
According to experts at a conference on transmission technology held in Singapore last week, among its many promises, the advancing technology puts an end to huge economic losses due to telecommunications failure caused by rising traffic.
The seminar was sponsored by giant telecom equipment-makers Alcatel and Lucent Technologies.
One of the latest transmission technologies is the Synchronous Digital Hierarchy (SDH) system, or its U.S. equivalent, Synchronous Optical Network (SONET), which has been increasingly applied by telecom carriers worldwide.
Laurie Doyle, of Alcatel's transmission division system, pointing out the estimated large business losses incurred by telecommunications failure, said an important feature of SDH is the prevention of this through its self-healing protection and automatic restoration mechanism.
He cited the 1987 average loss figure in the U.S., which was $3 million per hour for a major airline carrier, and $6 million per hour in a financial or trading institution.
Because of SDH's reliability, network operators would no longer need to have their maintenance crew working round the clock to fix network problems.
SDH also has the flexibility to adjust the network in a timely way to react to traffic changes as demand for telecom services rises. For past transmission networks, setting up a new end-user service would need a new network, which could take weeks or even months to install.
"The SDH network provides transverse compatibility between equipment produced by different manufacturers. The entire communications stream would no longer have to be torn apart and reassembled every time a signal has to be added or dropped," Doyle said
Instead, the signals are collected and routed through a grooming mechanism within a synchronous frame, he explained.
Another important feature of SDH is a lower cost of ownership thanks to its centralized network management.
The centralized management can greatly accelerate the provision of new services, allowing telecom operators to start new source of earnings much sooner.
This system could also determine the quality of services provided and measure slow resource degradation, thereby helping to anticipate future maintenance requirements before a fault actually occurs.
Alcatel's business development and communications director, Mario Pagani, said: "The SDH technology is future proof investment as it can be used together with the Wavelength Division Multiplexing (WDM) technology."
The WDM system is another transmission breakthrough boosting the transmission capacity by reusing the installed optical fibers, especially in metropolitan networks which have begun to show signs of fiber congestion.
The use of this new system is expected to increase over the next few years when a more sophisticated networking system, called "all-optical networks", is commercially available, providing the potential to manage and deliver an unprecedented amount of bandwidth capacity.
The highest transmission rate under the SDH system mostly used today is at 2.4 gigabits per second (Gbps); 10 Gbps capacity is also available.
By combining SDH with WDM, the capacity could be boosted to 400 Gbps per fiber.
Alcatel is the leader in the transmission systems market, holding 28 percent of market share worldwide. By far, Alcatel has the largest installed base of optical networks in the European market.
The company is currently involved in the world's longest and most complex undersea fiber optic telecom system, which stretches more than 30,000 km, connecting the Pacific Rim, Southeast Asia, the Middle East and Western Europe.
By combining the use of SDH and WDM, the project is capable of carrying 500,000 telephone conversations simultaneously.
Alcatel is the major supplier of SDH and WDM equipment, undersea cables and electronics.
Customer testing of the project is scheduled for the middle of 1998, with the first part of the network scheduled to enter service at the end of the year.
In Indonesia, Alcatel's SDH system is being used to develop PT Telkom's network in Java; PT Indosat's backbone network connecting Jakarta-Surabaya; and in several other transmission projects.
About 50 percent of Indonesia's telecommunications network has been installed using SDH, with several new transmission projects to be tendered soon, including installing a WDM system in the Maluku-Irian Jaya regional network.