02/09/98 WILL ZIP CODES FOR E-MAIL BE NEXT?

WILL ZIP CODES FOR E-MAIL BE NEXT?

ELECTRONIC TRAFFIC COPS called ''routers'' ideally can zip messages around the Internet at a mind-boggling 1 billion bits per second. But in heavy traffic, even the fastest routers can bog down. Routers have to study the address on each message and match the portion pertaining to the next leg of the journey to route information in giant databases. That can take upwards of 100 nanoseconds--speedy enough in human terms, but an eternity in network time.
The problem will get even worse in a few years, says computer scientist George Varghese at Washington University in St. Louis. Today, each destination address is a fairly short string of 32 bits (4 bytes of zeros and ones). Within five years, as Internet traffic surges, these will all be replaced by 128-bit addresses.
Preparing for that day, Varghese and his colleagues have patented a mathematical trick to speed up router performance--a solution Varghese compares to playing a game of 20 questions. The router begins by dividing addresses in half and comparing one half to a database. It will keep it or discard it in favor of the other half, and then repeat the process. With this method, the router will find the needed info in no more than seven steps. Several large router makers are now negotiating licensing deals with Washington University.
By Neil Gross
EDITED BY OTIS PORT