Cable TV

I have some comments about your feature on cable modems (March 4). The cable modem is an afterthought of cable TV companies. Cable TV companies distribute television signals via coaxial cable. In contrast, here in Indonesia, the signal is distributed via satellite, as Indovision does. Cable modems are good for countries with high penetration of cable TV such as the U.S., France, Australia or Germany.

But even for those countries, cable modems may not be the answer. Cable TV networks are designed as a one-way street. From the cable TV distributor to homes. In contrast, Internet signals travel both ways. Cable TV companies have an uphill battle -- not to mention the need of heavy investment -- to modify their networks to carry Internet signals.

Do not get excited about the promised rate bit. You will get only a fraction of it because another problem of cable TV is its topology. It is distributed tree-like. It branches out from a trunk, spreading by branching again to the fringes. That means, the farther a consumer is from the distribution point the more congestion he will face if this network is engineered for Internet traffic.

The coaxial cable -- to which cable modems will be connected -- is a shared medium. It means if you are my neighbor and I am in with three Web browsers opened simultaneously -- one downloading those NASA pictures of Mount Merapi, another downloading Silicon Valley's San Jose Mercury News and another Curitiba's Gazeta do Povo -- I will slow Internet connection down to a crawl because we are in the same "pipe". Moreover, do not discount Asymmetric Digital Subscriber Lines (ADSL) yet. But for ADSLs I would need another letter.

OSVALDO COELHO

Jakarta